WO2018181463A1 - 固体撮像装置、固体撮像装置の駆動方法、および電子機器 - Google Patents
固体撮像装置、固体撮像装置の駆動方法、および電子機器 Download PDFInfo
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- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
- H04N25/76—Addressed sensors, e.g. MOS or CMOS sensors
- H04N25/77—Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components
- H04N25/772—Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components comprising A/D, V/T, V/F, I/T or I/F converters
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- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
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- H01L27/14643—Photodiode arrays; MOS imagers
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Definitions
- the present invention relates to a solid-state imaging device, a driving method for the solid-state imaging device, and an electronic apparatus.
- CMOS Complementary Metal Oxide Semiconductor
- image sensor solid-state imaging device
- CMOS image sensors are widely applied as a part of various electronic devices such as digital cameras, video cameras, surveillance cameras, medical endoscopes, personal computers (PCs), and mobile terminal devices (mobile devices) such as mobile phones. Yes.
- the CMOS image sensor has an FD amplifier having a photodiode (photoelectric conversion element) and a floating diffusion layer (FD: Floating Diffusion) for each pixel, and the readout selects one row in the pixel array.
- FD floating diffusion layer
- a column parallel output type in which these are simultaneously read in the column output direction is the mainstream.
- CMOS image sensor By the way, in the CMOS image sensor, an operation of sequentially scanning and reading out the photoelectric charge generated and accumulated by the photodiode for each pixel or for each row is performed.
- this rolling scan that is, when a rolling shutter is employed as an electronic shutter, the start time and end time of exposure for accumulating photocharges cannot be made to coincide for all pixels. Therefore, in the case of sequential scanning, there is a problem that a captured image is distorted when a moving subject is imaged.
- exposure is started at the same timing for all pixels in the pixel array unit as an electronic shutter.
- a global shutter that executes the end of exposure is employed.
- CMOS image sensor that employs a global shutter as an electronic shutter
- a signal holding unit that holds a signal read from a photoelectric conversion reading unit in a signal holding capacitor is provided in a pixel.
- CMOS image sensor employing a global shutter electric charges from photodiodes are accumulated as voltage signals all at once in a signal holding capacitor of a signal holding unit, and then sequentially read out to ensure simultaneity of the entire image (for example, Non-Patent Document 1).
- This CMOS image sensor has a bypass switch that bypasses the signal holding unit and transfers the output of the photoelectric conversion readout unit to the signal line, and has a rolling shutter function in addition to the global shutter function. Has been.
- the stacked CMOS image sensor described in Non-Patent Document 1 has a stacked structure in which a first substrate (Pixel die) and a second substrate (ASIC die) are connected through microbumps (connection portions).
- a photoelectric conversion readout unit for each pixel is formed on the first substrate, and a signal holding unit, a signal line, a vertical scanning circuit, a horizontal scanning circuit, a column readout circuit, etc. are formed on the second substrate. ing.
- Non-Patent Document 2 describes a configuration example of a column readout circuit of a CMOS image sensor (FIG. 5).
- This column readout circuit has a configuration corresponding to a rolling shutter function, and includes a column amplifier, a correlated double sampling (CDS) circuit, and an analog-digital converter (ADC). .
- CDS correlated double sampling
- ADC analog-digital converter
- a column readout circuit has a capacitor capacity for holding a reset level and a signal level of pixel output, and different pixel output signals are arranged for each function.
- AD converter it is necessary to perform processing by an AD converter, and the area occupied by the capacitor capacity and the power consumption for driving it are problematic.
- the readout reset signal and readout luminance signal are sequentially read from the pixels and processed by the column readout circuit.
- the global shutter mode the readout luminance signal and readout reset signal are read out in order from the pixel and processed by the column readout circuit. Therefore, the current situation is that the column readout circuit must be configured separately for the rolling shutter function and the global shutter function.
- a readout signal read from the pixel a case of a single end signal or a case of a differential signal can be considered. And disadvantages such as complicating control.
- the present invention makes it possible to share a readout circuit regardless of the operation mode and the signal form of the readout signal, and thus, solid-state imaging capable of realizing a reduction in circuit scale, easy control, and low power consumption.
- An apparatus, a driving method of a solid-state imaging device, and an electronic apparatus are provided.
- a solid-state imaging device includes a pixel unit in which pixels that perform photoelectric conversion are disposed, and analog digital (AD) that converts a pixel signal read from the pixel to a signal line from an analog signal to a digital signal.
- AD analog digital
- a read circuit having a conversion function wherein the pixel signal read from the pixel includes a first pixel signal including a read reset signal and a read luminance signal sequentially read from the pixel by a first operation; And a second pixel signal including a readout luminance signal and a readout reset signal that are sequentially read out from the pixel by the operation of 2, and the readout circuit includes an amplification unit that amplifies the pixel signal;
- the AD signal that converts the pixel signal amplified by the amplifying unit from an analog signal to a digital signal in association with the search signal. It includes a part, and wherein the first first when the pixel signal of the second search signal when the searching signal and the second pixel signal can be set in a relationship search level is inverted.
- the second aspect of the present invention has a pixel portion in which pixels that perform photoelectric conversion are arranged, and an analog-to-digital (AD) conversion function that converts a pixel signal read from the pixel to a signal line from an analog signal to a digital signal.
- the pixel signal read from the pixel is a first pixel signal including a read reset signal and a read luminance signal that are sequentially read from the pixel by a first operation.
- the search signal supplied to the readout circuit is at least one of a first search signal for the first pixel signal and a second search signal for the second pixel signal. The search level is reversed.
- An electronic apparatus includes a solid-state imaging device and an optical system that forms a subject image on the solid-state imaging device, and the solid-state imaging device includes pixels that perform photoelectric conversion.
- a pixel circuit, and a readout circuit having an analog-digital (AD) conversion function for converting a pixel signal read from the pixel to a signal line from an analog signal into a digital signal, and the pixel signal read from the pixel is: A first pixel signal including a read reset signal and a read luminance signal sequentially read from the pixels by the first operation, and a second pixel including a read luminance signal and a read reset signal sequentially read from the pixels by the second operation.
- AD analog-digital
- a pixel signal, and the readout circuit includes: an amplification unit that amplifies the pixel signal; and the amplification unit.
- An AD converter that converts the widened pixel signal from an analog signal to a digital signal in association with the search signal, and includes the first search signal and the second pixel signal of the first pixel signal.
- the second search signal at that time can be set in a relationship in which the search level is inverted.
- the present invention it is possible to share a read circuit regardless of the operation mode and the signal form of the read signal, and as a result, it is possible to reduce the circuit scale, facilitate control, and reduce power consumption.
- FIG. 1 is a block diagram illustrating a configuration example of a solid-state imaging apparatus according to the first embodiment of the present invention.
- FIG. 2 is a circuit diagram illustrating an example of the first pixel and the second pixel of the solid-state imaging device according to the first embodiment of the present invention.
- FIG. 3 is a diagram for explaining the pixel array in the pixel portion of the solid-state imaging device according to the first embodiment of the present invention.
- FIG. 4 is a diagram for explaining a configuration example of a column output readout system of the pixel unit of the solid-state imaging device according to the embodiment of the present invention.
- FIG. 5 is a circuit diagram illustrating a configuration example of the column readout circuit of the solid-state imaging device according to the first embodiment of the present invention.
- FIG. 6 is a diagram for explaining a stacked structure of the solid-state imaging device according to the first embodiment.
- FIGS. 7A to 7D are timing charts for mainly explaining the reading operation in the pixel portion in the rolling shutter mode of the solid-state imaging device according to the first embodiment.
- FIGS. 8A to 8L are timing charts for explaining mainly the reading operation in the column reading circuit in the rolling shutter mode of the solid-state imaging device according to the first embodiment.
- FIGS. 9A to 9G are timing charts mainly for explaining the reading operation in the pixel portion in the global shutter mode of the solid-state imaging device according to the first embodiment.
- (A) to (L) are timing charts for mainly explaining the reading operation in the column reading circuit in the global shutter mode of the solid-state imaging device according to the first embodiment.
- FIG. 11 is a diagram illustrating a configuration example of the pixel and column readout circuit of the solid-state imaging device according to the second embodiment of the present invention.
- FIGS. 12A to 12K are timing charts for mainly explaining the reading operation in the column reading circuit in the differential rolling shutter mode of the solid-state imaging device according to the second embodiment.
- FIG. 13 is a diagram illustrating a configuration example of the first pixel of the solid-state imaging device according to the third embodiment of the present invention.
- FIGS. 14A to 14F are timing charts for mainly explaining the reading operation in the pixel section in the global shutter mode of the solid-state imaging device according to the third embodiment.
- FIG. 15A to 15L are timing charts for mainly explaining the reading operation in the column reading circuit in the global shutter mode of the solid-state imaging device according to the third embodiment.
- FIG. 16 is a circuit diagram showing a configuration example of the first operational amplifier of the column readout circuit according to the third embodiment.
- FIG. 17 is a diagram for explaining an example of control of the input range of the first operational amplifier in the differential global shutter mode.
- FIG. 18 is a circuit diagram showing a configuration example of a column read circuit according to the fourth embodiment of the present invention.
- 19A and 19B are diagrams for explaining a configuration example of a search signal input unit corresponding to the inverted binary search method employed in the AD conversion unit according to the fourth embodiment. It is a figure which shows an example of a structure of the electronic device to which the solid-state imaging device which concerns on embodiment of this invention is applied.
- Solid-state imaging device 20, 20A, 20B: Pixel unit, PD21, PD22 ... Photodiode, TG1-Tr, TG2-Tr ... Transfer transistor, RST1-Tr, RST2 -Tr ... reset transistor, SF1-Tr, SF2-Tr, SF3-Tr ... source follower transistor, SEL1-Tr, SEL2-Tr, SEL3-Tr ... selection transistor, FD21, FD22 ... floating Diffusion, 21 ... first pixel, 211 ... photoelectric conversion readout unit, 212 ... signal holding unit, 22 ... second pixel, 221 ... photoelectric conversion readout unit, 30 ...
- Vertical scanning circuit 40, 40C... Readout circuit (column readout circuit), 420... Amplification section, 430.
- PRC Signal processing circuit
- FIG. 1 is a block diagram illustrating a configuration example of a solid-state imaging apparatus according to the first embodiment of the present invention.
- the solid-state imaging device 10 is configured by, for example, a CMOS image sensor.
- the solid-state imaging device 10 includes a pixel unit 20 as an imaging unit, a vertical scanning circuit (row scanning circuit) 30, a readout circuit (column readout circuit) 40, and a horizontal scanning circuit (column scanning circuit) 50. , And a timing control circuit 60 as main components.
- the vertical scanning circuit 30, the readout circuit 40, the horizontal scanning circuit 50, and the timing control circuit 60 constitute a pixel signal readout unit 70.
- the solid-state imaging device 10 includes a first pixel including a photoelectric conversion readout unit and a signal holding unit as pixels, and a photoelectric conversion readout unit in the pixel unit 20, as will be described in detail later.
- a stacked CMOS image sensor having both the operation functions of the rolling shutter as the first operation and the global shutter as the second operation is mixed.
- the pixel unit 20 includes a first pixel array in which photoelectric conversion readout units of a plurality of first pixels are arranged in a matrix, and a plurality of first pixels.
- the signal holding units are configured to include a holding unit array in which the signal holding units are arranged in a matrix, and a second pixel array in which the photoelectric conversion readout units of the plurality of second pixels are arranged in a matrix.
- the rolling shutter mode which is the first operation
- the readout signals of the photoelectric conversion readout units of the first pixel and the second pixel are immediately output without following the bypass path to the first vertical signal line.
- the global shutter mode which is the second operation
- the holding signal of the signal holding unit of the first pixel is output to the second vertical signal line.
- the column readout circuit 40 performs amplification processing and AD conversion processing on the pixel readout signal transmitted through the first vertical signal line or the second vertical signal line.
- the column readout circuit 40 is one regardless of the operation mode and the signal form of the readout signal (signal such as single end or differential). It can be shared by two circuit configurations.
- FIG. 2 is a circuit diagram illustrating an example of the first pixel and the second pixel of the solid-state imaging device 10 according to the first embodiment of the present invention.
- the first pixel 21 arranged in the pixel unit 20 includes a photoelectric conversion readout unit 211 and a signal holding unit 212.
- the second pixel 22 disposed in the pixel unit 20 includes a photoelectric conversion readout unit 221.
- the photoelectric conversion readout unit 211 of the first pixel 21 includes a photodiode (photoelectric conversion element) and an in-pixel amplifier.
- the photoelectric conversion readout unit 211 includes a photodiode PD21 that is a photoelectric conversion element, for example.
- a transfer transistor TG1-Tr as a transfer element
- a reset transistor RST1-Tr as a reset element
- a source follower transistor SF1-Tr as a source follower element
- an output node ND21 and a selection element (selection switch)
- Selection switch selection switch
- the photoelectric conversion readout unit 211 of the first pixel 21 includes the transfer transistor TG1-Tr, the reset transistor RST1-Tr, the source follower transistor SF1-Tr, and the selection transistor SEL1-Tr. 4 transistors (4Tr) are included.
- the output node ND21 is connected to the input unit of the signal holding unit 212 of the first pixel 21, and the first vertical signal line is connected via the selection transistor SEL1-Tr. It is connected to LSGN11.
- the photoelectric conversion readout unit 211 outputs a readout reset signal (signal voltage) (VRST1) and a readout luminance signal (signal voltage) (VSIG1), which are the first pixel signal pixout1, to the first vertical signal line LSGN11 in the rolling shutter mode. To do.
- the photoelectric conversion readout unit 211 outputs a readout luminance signal (signal voltage) (VSIG1) and a readout reset signal (signal voltage) (VRST1), which are the second pixel signal pxout2, in the global shutter mode to the signal holding unit 212.
- VSIG1 readout luminance signal
- VRST1 readout reset signal
- the first vertical signal line LSGN11 is driven by the constant current source Ibias1 in the rolling shutter mode
- the second vertical signal line LSGN12 is driven by the constant current source Ibias1 in the global shutter mode.
- the constant current source Ibias1 is shared by the rolling shutter mode and the global shutter mode.
- the constant current source Ibias1 is switched in connection destination according to the operation mode by the switch unit 410.
- the first vertical signal line LSGN11 is connected to the constant current source Ibias1
- the second vertical signal line LSGN12 is connected to the reference potential VSS (for example, ground).
- the second vertical signal line LSGN12 is connected to the constant current source Ibias1
- the first vertical signal line LSGN11 is connected to the reference potential VSS (for example, ground).
- the photodiode PD21 generates and accumulates signal charges (here, electrons) corresponding to the amount of incident light.
- signal charges here, electrons
- each transistor is an n-type transistor
- the signal charge may be a hole or each transistor may be a p-type transistor.
- the present embodiment is also effective when a plurality of photodiodes and transfer transistors share each transistor.
- the transfer transistors TG1-Tr of the photoelectric conversion readout unit 211 are connected between the photodiode PD21 and the floating diffusion FD21, and are controlled by a control signal TG applied to the gate through the control line.
- the transfer transistors TG1-Tr are in a conductive state when the control signal TG is selected during a transfer period in which the control signal TG is high (H), and transfer charges (electrons) photoelectrically converted and accumulated by the photodiode PD21 to the floating diffusion FD21.
- the reset transistors RST1-Tr are connected between the power supply potential VDD and the floating diffusion FD21, and are controlled by a control signal RST applied to the gate through the control line.
- the reset transistors RST1-Tr are turned on when the control signal RST is selected during the reset period when the H level is reset, and reset the floating diffusion FD21 to the potential of the power supply voltage VDD.
- the source follower transistor SF1-Tr and the selection transistor SEL1-Tr are connected in series between the power supply potential VDD and the first vertical signal line LSGN11 driven by the constant current source Ibias1.
- An output node ND21 is formed by a connection point between the source of the source follower transistor SF1-Tr and the drain of the selection transistor SEL1-Tr.
- the signal line LSGN13 between the output node ND21 and the input unit of the signal holding unit 212 is driven by, for example, a constant current source Ibias3 arranged at the input unit of the signal holding unit 212.
- the source follower transistor SF1-Tr is a column output read reset signal (VRST1) and read luminance signal (VSIG1) or read luminance signal (VSIG1) and read reset signal obtained by converting the charge of the floating diffusion FD21 into a voltage signal corresponding to the amount of charge. (VRST1) is output to the output node ND21.
- a floating diffusion FD21 is connected to the gate of the source follower transistor SF1-Tr, and the selection transistors SEL1-Tr are controlled by a control signal SEL applied to the gate through a control line.
- the selection transistors SEL1-Tr are turned on when the control signal SEL is selected during a selection period of H level.
- the source follower transistor SF1-Tr outputs the read reset signal (VRST1) and the read luminance signal (VSIG1) obtained by converting the charge of the floating diffusion FD21 into a voltage signal corresponding to the amount of charge to the first vertical signal line LSGN11. .
- the signal holding unit 212 of the first pixel 21 basically includes an input unit 2121 to which the constant current source Ibias3 is connected, a sample hold unit 2122, an output unit 2123, and nodes ND22 to ND24.
- the constant current source Ibias3 is connected between the node ND22 and the reference potential VSS, and is controlled to be in an on state, for example, during a predetermined period during the global shutter period.
- a switch element connected between the node ND22 and the reference potential VSS and controlled to be in an on state during a predetermined period in the global shutter period may be provided.
- the sample hold unit 2122 includes a switch element SW21 that selectively connects the signal holding capacitor of the sample hold unit 2122 to the output node ND21 of the photoelectric conversion readout unit 211 and the first pixel 21 in the global shutter period that is the second period.
- Signal holding capacitors C21 and C22 capable of holding a signal output from the output node ND21 of the photoelectric conversion readout unit 211, and a reset transistor RST3-Tr for resetting the no ND24.
- a terminal a of the switch element SW21 is connected to an input node ND22 connected to the third signal line LSGN13, and a terminal b is connected to a node ND23 connected to the sample hold unit 2122 side.
- the switch element SW21 becomes conductive when terminals a and b are connected, for example, during a period when the signal sw1 is at a high level.
- the signal holding capacitor C21 is connected between the node ND23 and the node ND24.
- the signal holding capacitor C22 is connected between the node ND24 and the reference potential VSS.
- the reset transistor RST3-Tr is connected between the power supply potential VDD and the node ND24, and is controlled by a control signal RST3 applied to the gate through the control line.
- the reset transistors RST3-Tr are turned on when the control signal RST3 is selected during the reset period of the H level, and reset the node ND24 (and the capacitors C21, C22) to the potential of the power supply voltage VDD.
- the output unit 2123 includes a source follower transistor SF3-Tr that outputs a signal held in the signal holding capacitors C21 and C22 in accordance with the holding voltage during the global shutter period, which is the second period, and selectively holds the held signal.
- the signal is output to the second vertical signal line LSGN12 driven by the constant current source Ibias1 through the selection transistor SEL3-Tr.
- the source follower transistor SF3-Tr and the selection transistor SEL3-Tr are connected in series between the power supply potential VDD and the second vertical signal line LSGN12 driven by the constant current source Ibias1.
- a node ND24 is connected to the gate of the source follower transistor SF3-Tr, and the selection transistor SEL3-Tr is controlled by a control signal SEL3 applied to the gate through a control line.
- the selection transistors SEL3-Tr are turned on when the control signal SEL3 is selected during the selection period of the H level.
- the source follower transistor SF3-Tr outputs a column output read voltage (VRST, VSIG) corresponding to the holding voltage of the signal holding capacitors C21, C22 to the second vertical signal line LSGN12.
- the configuration of the signal holding unit 212 described above is an example, and the readout luminance signal (VSIG1) and readout reset signal (VRST1) output from the photoelectric conversion readout unit 211 described above during the global shutter period that is the second period.
- Any circuit may be used as long as it is a circuit having a function of holding
- the second pixel 22 disposed in the pixel unit 20 includes a photoelectric conversion readout unit 221.
- the photoelectric conversion readout unit 221 of the second pixel 22 has the same configuration as the photoelectric conversion readout unit 211 of the first pixel 21 described above.
- the photoelectric conversion readout unit 221 of the second pixel 22 includes a photodiode (photoelectric conversion element) and an in-pixel amplifier.
- the photoelectric conversion readout unit 221 includes a photodiode PD22 that is a photoelectric conversion element, for example.
- a transfer transistor TG2-Tr as a transfer element
- a reset transistor RST2-Tr as a reset element
- a source follower transistor SF2-Tr as a source follower element
- selection switch Each has one transistor SEL2-Tr.
- the photoelectric conversion readout unit 221 of the second pixel 22 includes the transfer transistor TG2-Tr, the reset transistor RST2-Tr, the source follower transistor SF2-Tr, and the selection transistor SEL2-Tr. 4 transistors (4Tr) are included.
- the photoelectric conversion read unit 221 outputs a read reset signal (signal voltage) (VRST2) and a read luminance signal (signal voltage) (VSIG2) to the first vertical signal line LSGN11 in the rolling shutter mode. To do.
- the photodiode PD22 generates and accumulates signal charges (here, electrons) corresponding to the amount of incident light.
- signal charges here, electrons
- each transistor is an n-type transistor
- the signal charge may be a hole or each transistor may be a p-type transistor.
- the present embodiment is also effective when a plurality of photodiodes and transfer transistors share each transistor.
- the transfer transistor TG2-Tr of the photoelectric conversion readout unit 221 is connected between the photodiode PD22 and the floating diffusion FD22, and is controlled by a control signal TG applied to the gate through the control line.
- the transfer transistors TG2-Tr are in the conductive state when the control signal TG is selected during the H level transfer period, and transfer the charges (electrons) photoelectrically converted and accumulated by the photodiode PD22 to the floating diffusion FD22.
- the reset transistor RST2-Tr is connected between the power supply potential VDD and the floating diffusion FD22, and is controlled by a control signal RST applied to the gate through the control line.
- the reset transistors RST2-Tr are turned on when the control signal RST is selected during the H level reset period and reset the floating diffusion FD22 to the potential of the power supply voltage VDD.
- the source follower transistor SF2-Tr and the selection transistor SEL2-Tr are connected in series between the power supply potential VDD and the first vertical signal line LSGN11 driven by the constant current source Ibias1.
- a floating diffusion FD22 is connected to the gate of the source follower transistor SF2-Tr, and the selection transistor SEL2-Tr is controlled by a control signal SEL applied to the gate through a control line.
- the selection transistors SEL2-Tr are turned on when the control signal SEL is selected during the selection period of the H level.
- the source follower transistor SF2-Tr converts the column output read reset signal (VRST2) and read luminance signal (VSIG2) obtained by converting the charge of the floating diffusion FD22 into a voltage signal corresponding to the charge amount to the first vertical signal line LSGN11. Output to.
- a first pixel 21 and a second pixel 22 having the above-described configuration are arranged as a pixel array, for example, as shown in FIG. An array is combined.
- FIG. 3 is a diagram for explaining a pixel array in the pixel unit 20 of the solid-state imaging device 10 according to the first embodiment of the present invention.
- the pixel unit 20 of the solid-state imaging device 10 includes a first pixel array 230, a holding unit array 240, an upper second pixel array 250-1, and a lower second pixel array 250. -2.
- the photoelectric conversion readout units 211 of the plurality of first pixels 21 are arranged in a two-dimensional matrix (matrix) of N rows ⁇ M columns.
- the photoelectric conversion readout unit 211 of the plurality of first pixels 21 is in a two-dimensional matrix form of N rows ⁇ M columns so that an image with an aspect ratio of 16: 9 can be output. Arranged in a matrix).
- the signal holding units 212 of the plurality of first pixels 21 are arranged in a two-dimensional matrix (matrix) of N rows ⁇ M columns corresponding to the first pixel array 230. .
- the holding unit array 240 includes N rows ⁇ M columns of signal holding units 212 for the plurality of first pixels 21 so that an image with an aspect ratio of, for example, 16: 9 can be output.
- Matrix a two-dimensional matrix
- the upper second pixel array 250-1 includes photoelectric conversion readout units 221 of a plurality of second pixels 22 arranged in a two-dimensional matrix (matrix) of P (P ⁇ N) rows ⁇ M columns. Yes.
- the photoelectric conversion readout unit 221 of the plurality of second pixels 22 has a two-dimensional matrix shape (matrix shape) of P (P ⁇ N) rows ⁇ M columns. Is arranged.
- the second pixel arrays 250-1 and 250-2 are disposed on both sides (upper and lower sides) of the first vertical signal line LSGN11 in the first pixel array 230 in the wiring direction.
- the second pixel array 250 may be disposed on at least one side of both sides of the first vertical signal line LSGN11 in the wiring direction of the first pixel array 230.
- the second pixel arrays 250-1 and 250-2 are activated together with the first pixel array 230 in the rolling shutter mode so that an image having an aspect ratio of 1: 1 can be output as a whole.
- the photoelectric conversion readout units 221 of the second pixels 22 are arranged in a two-dimensional matrix (matrix) of P (P ⁇ N) rows ⁇ M columns.
- the aspect ratio may be an arbitrary ratio such as 4: 3.
- the first pixel array 230 may be used as an area for electronic camera shake correction to output an image with an aspect ratio of 16: 9.
- the photoelectric conversion readout units 211 in the same column of the first pixel array 230 and the second pixel arrays 250-1 and 250-2 are connected to the common first vertical signal line LSGN11.
- the solid-state imaging device 10 has a laminated structure of a first substrate (upper substrate) and a second substrate (lower substrate), the first pixel array 230 and the second substrate are formed on the first substrate. Pixel arrays 250-1 and 250-2 are formed, and the holding unit array 240 is formed on the second substrate so as to face the first pixel array 230.
- the pixel unit 20 activates the first pixel array 230 and the second pixel arrays 250-1 and 250-2 in the rolling shutter mode, which is the first operation under the control of the reading unit 70, so that the pixels are sequentially arranged.
- the pixel signal is read out and accessed in units of rows.
- the pixel unit 20 controls the photoelectric conversion reading unit of the first pixel array 230 and the second pixel arrays 250-1 and 250-2 in the global shutter mode which is the second operation under the control of the reading unit 70.
- the selection transistors SEL1-Tr and SEL2-Tr in 221 are in a non-selected state (the signal SEL is at a low level)
- the first pixel array 230 and the holding unit array 240 are activated to read out pixel signals.
- the gates of the transfer transistor TG-Tr, reset transistor RST-Tr, and selection transistor SEL-Tr are connected in units of rows. Is called.
- each of the control lines LSEL, LRST, and LTG has (N + 2P) lines, the first vertical signal line LSGN11, and the second vertical signal line.
- the vertical scanning circuit 30 controls the photoelectric conversion readout unit 211 and the signal holding unit 212 of the first pixel 21 and the second pixel 22 through the row scanning control line in the shutter row and readout row according to the control of the timing control circuit 60.
- the photoelectric conversion readout unit 221 is driven. Further, the vertical scanning circuit 30 outputs a row selection signal of a row address of a read row that reads out the signal and a shutter row that resets the charge accumulated in the photodiode PD in accordance with the address signal.
- the column readout circuit 40 includes a plurality of column signal processing circuits (not shown) arranged corresponding to the respective column outputs of the pixel unit 20, and enables a column parallel processing by the plurality of column signal processing circuits. It may be configured.
- the column readout circuit 40 is connected to the first vertical signal line LSGN11 from the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22 in the rolling shutter mode which is the first operation.
- the read first pixel signal pixout1 (VSL1) and the second operation are read from the signal holding unit 212 of the first pixel 21 to the second vertical signal line LSGN12 in the global shutter mode which is the second operation.
- amplification processing and AD conversion processing are performed on the second pixel signal pixout2 (VSL2).
- the first pixel signal pixout1 (VSL1) is the pixel (in this example, the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout of the second pixel 22 in the rolling shutter mode which is the first operation).
- the second pixel signal pixout2 (VSL2) is read luminance sequentially read out from the pixels (in this example, the photoelectric conversion readout unit 211 of the first pixel 21 and further the signal holding unit 212) in the global shutter mode which is the second operation.
- the column readout circuit 40 can be shared by one circuit configuration regardless of the operation mode and the signal form of the readout signal (signal such as single end or differential). It is made possible.
- the column readout circuit 40 includes an amplifier (AMP) 41 and an ADC (analog / digital converter; AD converter) 42.
- the column readout circuit 40 amplifies the first pixel signal pixout1 (VSL1) and the second pixel signal pixout2 (VSL2), and is amplified by the amplification unit 420.
- the AD conversion unit 430 includes an AD converter that converts the analog readout signals VSL1 and VSL2 output from each column of the pixel unit 20 into digital signals.
- the column readout circuit 40 sends, for example, a signal transmitted through the first vertical signal line LSGN11 and a signal transmitted through the second vertical signal line LSGN12 to the column signal processing circuit of each column.
- a circuit for selectively inputting according to the operation mode is arranged.
- FIG. 5 is a circuit diagram showing a configuration example of the column readout circuit of the solid-state imaging device according to the first embodiment of the present invention.
- the column readout circuit 40 amplifies the first pixel signal pixout1 (VSL1), the second pixel signal pixout2 (VSL2), and the pixel signal amplified by the amplification unit 420.
- an AD conversion unit 430 that converts an analog signal into a digital signal in association with a search signal (for example, Vramp) is connected in cascade.
- An input unit 440 for selectively inputting to the input terminal is disposed.
- the amplifying unit 420 includes a first operational amplifier (hereinafter referred to as an operational amplifier) 421, a first sampling capacitor (input capacitor) Cs1, a first feedback capacitor (feedback capacitor) Cf1, a second sampling capacitor Cs2, a second The feedback capacitor Cf2, the first switch unit SW421, the second switch unit SW422, the first auto-zero switch unit SW423, the output node ND421, the offset potential VOS, and the reference potential Vref are configured.
- an operational amplifier hereinafter referred to as an operational amplifier
- the feedback capacitor Cf2 the first switch unit SW421, the second switch unit SW422, the first auto-zero switch unit SW423, the output node ND421, the offset potential VOS, and the reference potential Vref are configured.
- the first operational amplifier 421 has two input terminals, a first input terminal, which is an inverting input terminal ( ⁇ ) in the present embodiment, and a second input terminal, which is a non-inverting input terminal (+) in the present embodiment.
- the difference between the input voltage Vin1 to the first input terminal ( ⁇ ) and the input voltage Vin2 to the second input terminal (+) is multiplied (amplified) by a gain A0 to obtain an amplifier output ampout. If the gain (A0) is sufficiently high, when the negative feedback circuit is configured via the first switch unit SW421 or the first auto-zero switch unit SW423, The input terminal (+) is virtually grounded.
- the output terminal of the first operational amplifier 421 is connected to the output node ND421.
- the first sampling capacitor Cs1 includes a first output terminal TO1 of the input unit 440 as an input line end of the first pixel signal or the second pixel signal and a first input terminal ( ⁇ ) of the first operational amplifier 421. Connected between and.
- the second sampling capacitor Cs2 includes the second output terminal TO2 of the input unit 440 as the input line end of the first pixel signal or the second pixel signal and the second input terminal (+) of the first operational amplifier 421. Connected between and.
- the following pixel signals are supplied according to the four mode signals MOD1 to MOD4.
- the first mode signal MOD1 the single-ended first pixel signal pixout1 in the rolling shutter mode is supplied from the first output terminal TO1 of the input unit 440.
- the second mode signal MOD2 the single-ended second pixel signal pixout2 in the global shutter mode is supplied from the first output terminal TO1 of the input unit 440.
- the third mode signal MOD3 one first pixel signal pixout1d1 of the differential signals in the differential rolling shutter mode is supplied from the first output terminal TO1 of the input unit 440.
- the fourth mode signal MOD4 one second pixel signal pixout2d1 of the differential signals in the differential global shutter mode is supplied from the first output terminal TO1 of the input unit 440.
- the following pixel signals are supplied according to the four mode signals MOD1 to MOD4.
- the pixel signal is not supplied from the second output terminal TO2 of the input unit 440.
- the pixel signal is not supplied from the second output terminal TO2 of the input unit 440.
- the other first pixel signal pixout1d2 of the differential signals in the differential rolling shutter mode is supplied from the second output terminal TO2 of the input unit 440.
- the other second pixel signal pixout2d2 of the differential signals in the differential global shutter mode is supplied from the second output terminal TO2 of the input unit 440.
- the first feedback capacitor Cf1 has one electrode end connected to the first input terminal ( ⁇ ) of the first operational amplifier 421 and the other electrode end connected to the first switch unit SW421.
- the second feedback capacitor Cf2 has one electrode end connected to the second input terminal (+) of the first operational amplifier 421 and the other electrode end connected to a reference potential VSS (for example, ground GND).
- VSS for example, ground GND
- the terminal a is connected to the other electrode end of the first sampling capacitor Cf1
- the terminal b is connected to the output node ND421 (the output terminal of the first operational amplifier 421)
- the terminal c is offset. It is connected to the potential VOS.
- the control signal CKOS is at a low level (L)
- the first switch unit SW421 connects the terminal a to the terminal b
- the control signal CKOS is at a high level (H)
- the first switch unit SW421 connects the terminal a to the terminal c.
- the control signal CKOS includes a first mode signal MOD1 (single-ended rolling shutter mode) and a third mode signal MOD3 (differential rolling shutter mode) supplied to the input unit 440.
- the fourth mode signal MOD4 (differential global shutter mode) is supplied at the L level
- the second mode signal MOD2 (single-ended global shutter mode) is supplied with a clock. That is, in the first feedback capacitor Cf1, the mode signal supplied to the input unit 440 includes a first mode signal MOD1 (single-ended rolling shutter mode) and a third mode signal MOD3 (differential rolling shutter mode).
- the fourth mode signal MOD4 (differential global shutter mode)
- the fourth mode signal MOD4 is connected between the first input terminal ( ⁇ ) of the first operational amplifier 421 and the output node ND421.
- the first feedback capacitor Cf1 has a first input terminal ( ⁇ ) of the first operational amplifier 421 when the mode signal supplied to the input unit 440 is the second mode signal MOD2 (single-ended global shutter mode). Transitions between a state connected to the output node ND421 and a state connected to the offset potential VOS.
- the second switch unit SW422 has a terminal a connected to the second input terminal (+) of the first operational amplifier 421 and a terminal b connected to the reference potential Vref.
- the second switch unit SW422 is supplied with a control signal VREFSH as a clock. When the clock is at an H level, the terminals a and b are held in a conductive state (on state), and when the clock is at an L level, the terminals a and b are not connected. It is held in a conductive state (off state).
- the second switch unit SW422 When the mode signal supplied to the input unit 440 is the first mode signal MOD1 (single-end rolling shutter mode) and the second mode signal MOD2 (single-end global shutter mode), the second switch unit SW422 The terminals a and b are held in the conducting state (ON state), and are conducted when the third mode signal MOD3 (differential rolling shutter mode) and the fourth mode signal MOD4 (differential global shutter mode). The state (on state) and non-conduction state (off state) are transitioned.
- the mode signal supplied to the input unit 440 is the first mode signal MOD1 (single-end rolling shutter mode) and the second mode signal MOD2 (single-end global shutter mode)
- the second switch unit SW422 The terminals a and b are held in the conducting state (ON state), and are conducted when the third mode signal MOD3 (differential rolling shutter mode) and the fourth mode signal MOD4 (differential global shutter mode).
- the auto zero switch unit SW423 has a terminal a connected to the first input terminal ( ⁇ ) of the first operational amplifier 421 and a terminal b connected to the output node ND421 (output terminal of the first operational amplifier 421).
- the control signal AZ1 is at the H level
- the auto zero switch unit SW423 holds the terminal a and the terminal b in the conductive state (ON state)
- the control signal AZ1 is the L level
- the terminal a and the terminal b are held in the non-conductive state (OFF state).
- the first operational amplifier 421 is in a reset state when the auto zero switch unit SW423 is in a conductive state.
- the AD conversion unit 430 includes a second operational amplifier 431, a search signal input unit 432, a sample hold switch unit SW431, a third sampling capacitor Cs3, a second auto zero switch unit SW432, an input node ND431, and an output node ND432. It is configured.
- the second operational amplifier 431 has two input terminals, a first input terminal, which is an inverting input terminal ( ⁇ ) in the present embodiment, and a second input terminal, which is a non-inverting input terminal (+) in the present embodiment.
- the input signal voltage Vcmp supplied to the first input terminal ( ⁇ ) of the second operational amplifier 431 is the voltage held in the third sampling capacitor Cs3 and held in the fourth sampling capacitor Cs4 during AD conversion. And a signal voltage obtained by synthesizing the search signal Vramp by the search signal input unit 432.
- the search signal Vramp is a signal having a slope waveform that changes linearly with a certain slope.
- the search signal Vramp is supplied as a slope waveform with a downward slope to the right such that the left side has a high level and the right side has a low level like the first search signal Vramp1 in FIG.
- the search signal Vramp for example, as the second search signal Vramp2 in FIG. 5, the left side has a low-level level and the right side has a high level slope waveform.
- the first search signal Vramp1 and the second search signal Vramp2 have a relationship in which the search level, here, the level of the slope waveform is inverted.
- the mode signal supplied to the input unit 440 as the search signal Vramp is the first mode signal MOD1 (single-ended rolling shutter mode) and the third mode signal MOD3 (differential rolling shutter mode).
- the fourth mode signal MOD4 differential global shutter mode
- the first search signal Vramp1 is supplied to the search signal input unit 432.
- the second search signal Vramp2 is the search signal input unit. 432 is supplied.
- the search signal input unit 432 in FIG. 5 includes a fourth sampling capacitor (input capacitor) Cs4.
- the fourth sampling capacitor Cs4 is connected between the input node ND431 and the supply line of the search signal Vramp.
- the second operational amplifier 431 receives the input signal voltage Vcmp input to the first input terminal ( ⁇ ) via the third sampling capacitor Cs3 and the reference potential Vref2 supplied to the second input terminal (+). In comparison, when the input signal voltage Vcmp crosses the reference potential Vref2, the comparison output signal cmpout is switched from the L level to the H level or from the H level to the L level. AD conversion is performed by measuring the time until the intersection with a counter (not shown). As described above, the second operational amplifier 431 functions as a comparator.
- the third sampling capacitor (input capacitor) Cs3 is connected between the input node ND431 and the first input terminal ( ⁇ ) of the second operational amplifier 431.
- the sample hold switch unit SW431 has a terminal a connected to the output node ND421 of the amplifying unit 420 and a terminal b connected to the input node ND431.
- the sample hold switch unit SW431 for example, when the control signal SH is at the H level, the terminals a and b are held in the conductive state (on state), and when the control signal SH is at the L level, the terminals a and b are in the nonconductive state (off state). Retained.
- the AD conversion unit 430 causes the amplifier output ampout of the amplification unit 420 to be input to the input node ND431 when the sample hold switch unit SW431 is in a conductive state.
- the terminal a is connected to the first input terminal ( ⁇ ) of the second operational amplifier 431, and the terminal b is connected to the output node ND432 (output terminal of the second operational amplifier 431).
- the control signal AZ2 is at the H level
- the auto zero switch unit SW432 holds the terminal a and the terminal b in the conductive state (ON state)
- the control signal AZ2 is at the L level
- the terminal a and the terminal b are held in the non-conductive state (OFF state).
- the second operational amplifier 431 is in a reset state when the auto zero switch unit SW432 is in a conductive state.
- the first pixel signal pixout1 (VSL1) of the single end signal corresponding to the first mode signal MOD1 is input to the first sampling capacitor Cs1 of the amplifying unit 420.
- the first feedback capacitor Cf1 of the amplifying unit 420 is connected to the output node ND421 (output terminal of the first operational amplifier 421) by the first switch unit SW421, and the second input terminal (+) of the first operational amplifier 421. Is connected to the reference potential Vref.
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform that descends to the right through the search signal input unit 432.
- the amplifying unit 420 when the second pixel signal pixout2 (VSL2) of the single end signal corresponding to the second mode signal MOD2 is input to the amplifying unit 420 and the first sampling capacitor Cs1, the amplifying unit 420 is used.
- the feedback capacitor Cf1 is connected to the offset potential VOS or the output node ND421 (output terminal of the first operational amplifier 421) by the first switch unit SW421, and the second input terminal (+) of the first operational amplifier 421 is the reference potential.
- the AD conversion unit 430 is supplied with the second search signal Vramp2 having a slope waveform rising to the right through the search signal input unit 432 and having a level-inverted relationship with the first search signal Vramp1.
- the differential first pixel signals pixout1d1 (VSL1D1) and pixout1d2 (VSL1D2) corresponding to the third mode signal MOD3 are the first sampling capacitor Cs1 and the second sampling capacitor Cs1 of the amplifying unit 420.
- the feedback capacitor Cf1 of the amplifying unit 420 is connected to the output node ND421 (the output terminal of the first operational amplifier 421) by the first switch unit SW421.
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform that descends to the right through the search signal input unit 432.
- the differential second pixel signals pixout2d1 (VSL2D1) and pixout2d2 (VSL2D2) corresponding to the fourth mode signal MOD4 are used as the first sampling capacitor Cs1 and the second sampling capacitor Cs1 of the amplifying unit 420.
- the feedback capacitor Cf1 of the amplifying unit 420 is connected to the output node ND421 (the output terminal of the first operational amplifier 421) by the first switch unit SW421.
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform that descends to the right through the search signal input unit 432.
- the column readout circuit 40 of the first embodiment includes the pixel signal corresponding to the first mode signal MOD1, the second mode signal MOD2, the third mode signal MOD3, and the fourth mode signal MOD4. Can be processed.
- the pixel unit 20 is configured to generate a pixel signal corresponding to the first mode signal MOD1 and the second mode signal MOD2. Therefore, the column readout circuit 40 of the first embodiment uses the single-ended first pixel signal pixout1 (VSL1) and the second mode signal MOD2 in the rolling shutter mode according to the first mode signal MOD1.
- the single-ended second pixel signal pixout2 (VSL2) in the corresponding global shutter mode is processed.
- the horizontal scanning circuit 50 scans a signal processed by a plurality of column signal processing circuits such as an ADC of the column readout circuit 40, transfers it in the horizontal direction, and outputs it to a signal processing circuit (not shown).
- the timing control circuit 60 generates timing signals necessary for signal processing of the pixel unit 20, the vertical scanning circuit 30, the column readout circuit 40, the horizontal scanning circuit 50, and the like.
- the readout unit 70 activates the first pixel array 230 and the second pixel arrays 250-1 and 250-2 in the rolling shutter mode, which is the first operation, to sequentially process pixels.
- the first pixel signal pixout1 of the single end is read and accessed in units of rows.
- the readout unit 70 is in the photoelectric conversion readout unit 221 of the first pixel array 230 and the second pixel arrays 250-1 and 250-2 in the global shutter mode that is the second operation.
- Select transistor SEL1-Tr In a state where SEL2-Tr is in a non-selected state (signal SEL is at a low level), the first pixel array 230 and the holding unit array 240 are activated, and the single-ended second pixel signal pixout2 is read.
- FIG. 6 is a diagram for explaining a stacked structure of the solid-state imaging device 10 according to the first embodiment.
- the solid-state imaging device 10 has a stacked structure of a first substrate (upper substrate) 110 and a second substrate (lower substrate) 120.
- the solid-state imaging device 10 is formed as an imaging device having a laminated structure that is bonded at a wafer level and cut out by dicing, for example.
- the first substrate 110 is stacked on the second substrate 120.
- a first pixel array 230 is formed in which the photoelectric conversion read-out portions 211 of the first pixels 21 of the pixel unit 20 are arranged around the center thereof.
- Second pixel arrays 250-1 and 250-2 are formed on both sides (upper and lower sides) of the first vertical signal line LSGN11 in the wiring direction.
- a first vertical signal line LSGN 11 is formed on the first substrate 110.
- the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22 are formed in a matrix on the first substrate 110. ing.
- the signal holding units 212 of the first pixels 21 connected to the output nodes ND21 of the photoelectric conversion readout units 211 of the first pixel array 230 centering on the center are arranged in a matrix.
- the arranged holding unit array 240 (region 121) and the second vertical signal line LSGN12 are formed.
- the regions 122 and 123 for the column readout circuit 40 are formed around the holding unit array 240, and in the example of FIG. Note that the column readout circuit 40 may be configured to be disposed on either the upper side or the lower side of the region 121 of the holding unit array 240.
- a region 124 for the vertical scanning circuit 30 and a digital system or output system region 125 are formed on the side of the holding unit array 240.
- the vertical scanning circuit 30, the horizontal scanning circuit 50, and the timing control circuit 60 may also be formed on the second substrate 120.
- the input node ND21 of each photoelectric conversion readout unit 211 of the first pixel array 230 of the first substrate 110 and the input of the signal holding unit 212 of each first pixel 21 of the second substrate 120 are used.
- the node ND22 is electrically connected using vias (Die-to-Die Vias), micro-bumps, or the like.
- the first vertical signal line LSGN11 of the first substrate 110 and the input portion of the column readout circuit 40 of the second substrate 120 are respectively connected to vias (Die-to-Die Via) as shown in FIG. Electrical connection is made using micro bumps or the like.
- FIGS. 7A to 7D are timing charts for mainly explaining the reading operation in the pixel portion in the rolling shutter mode of the solid-state imaging device according to the first embodiment.
- FIGS. 8A to 8L are timing charts for mainly explaining the reading operation in the column reading circuit in the rolling shutter mode of the solid-state imaging device according to the first embodiment.
- FIG. 7A shows control signals SEL of the selection transistors SEL1-Tr and SEL2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 7B shows control signals RST of the reset transistors RST1-Tr and RST2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 7C shows control signals TG of the transfer transistors TG1-Tr and TG2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 7D shows the control signal sw1 of the switch element SW21 of the signal holding unit 212 of the first pixel 21 and the control signal SEL3 of the selection transistors SEL3-Tr.
- FIG. 8A shows an equivalent circuit of a pixel and column readout circuit
- FIG. 8B shows a selection transistor SEL1- of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- the control signal SEL for Tr and SEL2-Tr is shown.
- FIG. 8C shows the reset signals RST1-Tr and RST2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22, and the transfer transistor TG1-
- the control signals TG for Tr and TG2-Tr are shown.
- FIG. 8D shows the single-ended first pixel signal pixout1 in the rolling shutter mode
- FIG. 8E shows the control signal AZ1 of the auto-zero switch unit SW423, and FIG. 8F shows the first switch.
- 8G shows the control signal CKOS of the part SW421,
- FIG. 8G shows the control signal SH of the sample hold switch part SW431, and
- FIG. 8H shows the control signal AZ2 of the auto zero switch part SW432.
- 8I shows the output signal (amplifier output) ampout of the first operational amplifier 421
- FIG. 8J shows the first search signal Vramp1
- FIG. 8K shows the input of the second operational amplifier 431.
- the signal (signal voltage) Vcmp is shown
- FIG. 8 (L) shows the output signal (comparison output) cmpout of the second operational amplifier 431.
- the control signal sw1 of the switch element SW21 that controls the driving of all the signal holding units 212 of the holding unit array 240 and the control signal SEL3 that controls the selection transistors SEL3-Tr are at the L level.
- the switch element SW21 and the selection transistor SEL3-Tr are controlled to be non-conductive.
- the constant current source Ibias3 is controlled to be in an off state.
- the rolling shutter mode period all the signal holding units 212 of the holding unit array 240 formed on the second substrate 120 are not accessed.
- the first pixel array 230 and the second pixel arrays 250-1 and 250-2 formed on the first substrate 110 are sequentially accessed in units of rows.
- the selected row is selected.
- the control signal SEL for controlling (driving) each photoelectric conversion readout unit 211 of the first pixel array 230 or the photoelectric conversion readout unit 221 of the second pixel arrays 250-1 and 250-2 in the same row is set to the H level.
- the selection transistor SEL2-Tr (or SEL1-Tr) of the pixel becomes conductive.
- the reset transistor RST2-Tr (or RST1-Tr) is selected during the reset period PR while the control line RST is at the H level and becomes conductive, and the floating diffusion FD is reset to the potential of the power supply voltage VDD.
- the reset period PR elapses (the reset transistor RST2-Tr or RST1-Tr is in a non-conducting state)
- a period including a time t1 until the transfer period PT is started is the first to read out the pixel signal in the reset state. It becomes a reading period.
- the source follower transistor SF2-Tr (or SF1-Tr) of the selected row converts the charge of the floating diffusion FD22 (or FD21) into a voltage signal corresponding to the amount of charge, and a column output read reset signal VRST is immediately output to the first vertical signal line LSGN 11 and supplied to the column readout circuit 40.
- the first read period ends and the transfer period PT begins.
- the transfer transistor TG2-Tr (or TG1-Tr) is selected during the period when the control signal TG is at the high level (H) and becomes conductive, and is photoelectrically converted and stored by the photodiode PD22 (or PD21). Charges (electrons) are transferred to the floating diffusion FD22 (or FD21).
- the transfer transistor TG2-Tr or TG1-Tr is in a non-conductive state
- it includes a time t2 when the photodiode PD22 (or PD21) reads out a pixel signal corresponding to the charge accumulated by photoelectric conversion.
- the second readout period is entered.
- the source follower transistor SF2-Tr (or SF1-Tr) in the selected row converts the charge of the floating diffusion FD22 (or FD21) into a voltage signal corresponding to the amount of charge. Then, it is immediately output to the first vertical signal line LSGN 11 as a column output readout luminance signal VSIG and supplied to the column readout circuit 40.
- amplification processing and AD conversion processing are performed on the readout reset signal VRST and readout luminance signal VSIG of the first pixel signal pixout1 sequentially supplied, Also, the difference ⁇ VRST ⁇ VSIG ⁇ between the two signals is taken and the CDS process is performed.
- the first mode signal MOD1 is supplied to the input unit 440 of the column readout circuit 40.
- the control signal CKOS is supplied to the first switch unit SW421 of the amplification unit 420 of the column readout circuit 40 at the L level.
- the first switch unit SW421 has the terminal a connected to the terminal b, and the first feedback capacitor Cf1 is connected between the first input terminal ( ⁇ ) of the first operational amplifier 421 and the output node ND421. Connected between.
- the second switch unit SW422 of the amplification unit 420 of the column readout circuit 40 is held in a conductive state, and the second input terminal (+) of the first operational amplifier 421 is set to the reference potential Vref. It is connected.
- the first pixel signal is input to the input unit 440, and the single-ended first pixel signal pixout1 in the rolling shutter mode is output from the first output terminal TO1 of the input unit 440 to the first
- the voltage is supplied to the first input terminal ( ⁇ ) side of the first operational amplifier 421 to which the sampling capacitor Cs1 is connected.
- the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit of the second pixel 22 On the first input terminal ( ⁇ ) side of the first operational amplifier 421, as shown in FIG. 8D, the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit of the second pixel 22.
- a single-end read reset signal VRST and a read luminance signal VSIG are sequentially read from 221.
- a predetermined period after the read reset signal VRST is input (a predetermined period after the start of the first read period for reading the pixel signal in the reset state).
- control signals AZ1, SH, and AZ2 are set to the H level.
- the auto-zero switch unit SW423 of the amplification unit 420, the sample hold switch unit SW431 of the AD conversion unit 430, and the auto-zero switch unit SW432 become conductive.
- the period during which the control signals AZ1, SH, and AZ2 are set to the H level is set longer in the order of the control signals SH, AZ2, and AZ1.
- the first operational amplifier 421 of the amplification section 420 and the second operational amplifier 431 of the AD conversion section 430 are reset.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes the reference potential Vref and is transferred to the AD conversion unit 430 through the sample hold switch unit SW431, and the third sampling capacitor Cs3 and the fourth Of the sampling capacitor Cs4.
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform having a downward slope to the right through the search signal input unit 432.
- a signal voltage Vcmp obtained by synthesizing the voltage held in the fourth sampling capacitor Cs4 and the search signal Vramp1 by the search signal input unit 432 is the first input of the second operational amplifier 431. Supplied to the terminal (-) side.
- the comparison output signal cmpout is output at the H level as shown in FIG. By holding this H level period in a counter (not shown), AD conversion is performed.
- the amplifying unit 420 When the first readout period ends, the amplifying unit 420 is supplied with a readout luminance signal VSIG having a lower potential than the readout reset signal VRST.
- the output signal ampout of the first operational amplifier 421 is a level-amplified signal (Vref + G) obtained by multiplying the difference between the read reset signal VRST and the low-potential read luminance signal VSIG by the capacitance ratio multiple G with reference to the reference potential Vref. * (VRST-VSIG)). Then, during a predetermined period after the transfer period, as shown in FIG. 8G, the control signal SH is set to the H level, and the sample hold switch unit SW431 of the AD conversion unit 430 becomes conductive.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes a signal (Vref + G * (VRST ⁇ VSIG)), which is transferred to the AD conversion unit 430 through the sample hold switch unit SW431.
- Vref + G * VRST ⁇ VSIG
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform having a downward slope to the right through the search signal input unit 432.
- a signal voltage Vcmp obtained by synthesizing the voltage held in the fourth sampling capacitor Cs4 and the search signal Vramp1 by the search signal input unit 432 is the first input of the second operational amplifier 431. Supplied to the terminal (-) side.
- the comparison output signal cmpout is output at the H level as shown in FIG. By holding this H level period in a counter (not shown), AD conversion is performed.
- the difference ⁇ VRST ⁇ VSIG ⁇ between the readout reset signal VRST and the readout luminance signal VSIG is taken, and the CDS processing is performed.
- the first pixel array 230 and the second pixel arrays 250-1 and 250-2 formed on the first substrate 110 are sequentially accessed in units of rows.
- the read operations are sequentially performed.
- FIGS. 9A to 9G are timing charts mainly for explaining the reading operation in the pixel portion in the global shutter mode of the solid-state imaging device according to the first embodiment.
- FIGS. 10A to 10L are timing charts for mainly explaining the reading operation in the column reading circuit in the global shutter mode of the solid-state imaging device according to the first embodiment.
- FIG. 9A shows control signals SEL of the selection transistors SEL1-Tr and SEL2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 9B shows control signals RST of the reset transistors RST1-Tr and RST2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 9C shows control signals TG for the transfer transistors TG1-Tr and TG2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 9D shows the control signal sw ⁇ b> 1 of the switch element SW ⁇ b> 21 of the signal holding unit 212 of the first pixel 21.
- FIG. 9E shows the control signal RST3 of the reset transistors RST3-Tr of the signal holding unit 212 of the first pixel 21.
- FIG. 9F shows the control signal SEL3 of the selection transistors SEL3-Tr of the signal holding unit 212 of the first pixel 21.
- FIG. 9G shows the driving state (on / off state) of the constant current source Ibias3 arranged in the signal holding unit 212 of the first pixel 21.
- FIG. 10A shows an equivalent circuit of the pixel and column readout circuit
- FIG. 10B shows a control signal SEL3 of the selection transistors SEL3-Tr of the signal holding unit 212 of the first pixel 21
- FIG. 10C shows the control signal RST3 of the reset transistors RST3-Tr of the signal holding unit 212 of the first pixel 21
- FIG. 10D shows the single-ended second pixel signal pixout2 in the global shutter mode
- FIG. 10E shows the control signal AZ1 of the auto zero switch unit SW423
- FIG. 10F shows the first switch.
- 10G shows the control signal CKOS of the part SW421
- FIG. 10G shows the control signal SH of the sample hold switch part SW431, and FIG.
- 10H shows the control signal AZ2 of the auto zero switch part SW432.
- 10I shows the output signal (amplifier output) ampout of the first operational amplifier 421
- FIG. 10J shows the second search signal Vramp2
- FIG. 10K shows the input of the second operational amplifier 421.
- the signal voltage Vcmp is shown
- FIG. 10 (L) shows the output signal (comparison output) cmpout of the second operational amplifier 431.
- the control of the selection transistors SEL1-Tr and SEL2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22 is performed.
- the signal SEL is set to the low level (L) during the entire period of the global shutter mode. This suppresses (stops) the output of voltage signals from the first pixel array 230 and the second pixel arrays 250-1 and 250-2 to the first vertical signal line LSGN11 during the entire period of the global shutter mode. . Therefore, the second pixel arrays 250-1 and 250-2 are controlled to be inactive. Further, the first pixel array 230 is in an active state, and is in a state in which a voltage signal from the output node ND21 can be output to the signal holding unit 212.
- times t11 to t12 are a reset period and a charge accumulation period of the photodiode PD21 and the floating diffusion FD21 in all the photoelectric conversion readout units 211 of the first pixel array 230.
- sw1 the control signal RST3 for controlling the reset transistor RST3-Tr, and the control signal SEL3 for controlling the selection transistor SEL3-Tr are set to L level, and the switch element SW21, the reset transistor RST3-Tr, and the selection transistor SEL3-Tr are non-conductive.
- the constant current source Ibias3 is controlled to the off state.
- the reset transistors RST1-Tr are selected during the period when the control signal RST is at the H level and become conductive. Then, during the period when the control signal RST is at the H level, the transfer transistors TG1-Tr are selected during the period when the control signal TG is at the H level and become conductive, and the charge (electrons) accumulated by the photoelectric conversion by the photodiode PD21 is stored. The storage node becomes conductive with the floating diffusion FD21, and the photodiode PD21 and the floating diffusion FD21 are reset to the potential of the power supply voltage VDD.
- the control signal TG of the transfer transistor TG1-Tr is switched to the L level, the transfer transistor TG1-Tr is turned off, and the photodiode PD21 starts accumulating the photoelectrically converted charge.
- the control signal RST of the reset transistors RST1-Tr is held at the H level, and the floating diffusion FD21 is kept reset to the potential of the power supply voltage VDD.
- the control signal RST of the reset transistors RST1-Tr is switched to the L level, and the reset transistors RST1-Tr are turned off.
- a period including time t12 until the transfer period PT is started is a first readout period for reading out pixel signals in the reset state.
- the control signal RST3 for controlling the reset transistor RST3-Tr is switched to the H level for a predetermined period including the time t12, the reset transistor RST3-Tr is held in the conductive state, and the node ND24 is Reset to the potential of the power supply voltage VDD. Further, for a predetermined period including times t12, t13, and t14, the control signal sw1 of the switch element SW21 is held at the H level, and the switch element SW21 is held in the on state (conductive state). Similarly, the constant current source Ibias3 is controlled to be on for a predetermined period including times t12, t13, and t14. The constant current source Ibias3 is controlled to be turned off after the time t14 has elapsed and the control signal sw1 of the switch element SW21 is switched to the L level and the switch element SW21 is turned off (non-conducting state).
- the charge of the floating diffusion FD21 is converted into a voltage signal corresponding to the amount of charge by the source follower transistors SF1-Tr of all the pixels, and the third signal line LSGN13 is set as a pixel read reset signal VRST0.
- the signal holding unit 212 To the signal holding unit 212, and further held in the signal holding capacitor C21 through the switch element SW21.
- the first reading period ends, and a predetermined period including time t13 becomes the transfer period PT.
- the transfer transistors TG1-Tr are selected when the control signal TG is at the high level (H) and become conductive, and the charges (electrons) photoelectrically converted and stored by the photodiode PD21 are transferred to the floating diffusion FD21. Is done.
- a second readout period including a time t14 in which the pixel signal corresponding to the charge accumulated by photoelectric conversion by the photodiode PD2 is read out.
- the charge of the floating diffusion FD21 is converted into a voltage signal corresponding to the amount of charge by the source follower transistors SF1-Tr of all the pixels, and a third readout luminance signal VSIG0 of the pixel is obtained.
- the control signal SEL3 of each selection transistor SEL3-Tr in the selected row is set to H level.
- the selection transistor SEL3-Tr becomes conductive.
- the holding signal VSIG (VSIG-VRST) held in the signal holding capacitors C21 and C22 is read.
- column output is read out by the source follower transistor SF3-Tr whose gate is connected to the node ND24 according to the holding voltage of the signal holding capacitors C21 and C22 connected to the node ND24.
- the luminance signal (VSIG-VRST) is output to the second vertical signal line LSGN12 and supplied to the column readout circuit 40.
- the control signal RST3 is switched to the H level, the reset transistor RST3-Tr is turned on, and the node ND24 is reset.
- the reset holding signal (VRST) held in the signal holding capacitors C21 and C22 connected to the node ND24 is read.
- column output is read out by the source follower transistor SF3-Tr whose gate is connected to the node ND24 according to the holding voltage of the signal holding capacitors C21 and C22 connected to the node ND24.
- the reset signal (VRST) is output to the second vertical signal line LSGN 12 and supplied to the column readout circuit 40.
- the readout luminance signal (VSIG-VRST) read out during a predetermined period including time t15 and the readout read out during a predetermined period including time t16.
- the reset signal VRST is sequentially supplied to the amplifying unit 420 as the second pixel signal pixout2.
- the column readout circuit 40 that constitutes a part of the readout unit 70, amplification processing and AD conversion for the readout luminance signal VSIG (CMS) and readout reset signal VRST of the second pixel signal pixout2 sequentially supplied through the input unit 440 Processing is performed. Further, the difference ⁇ VSIG ⁇ VRST ⁇ between the two signals is taken and further CDS processing is performed to cancel the offset voltage of the source follower transistor SF3-Tr.
- CMS readout luminance signal
- VRST readout reset signal
- the second mode signal MOD2 is supplied to the input unit 440 of the column readout circuit 40 in the single-ended global shutter mode period.
- the second switch unit SW422 of the amplification unit 420 of the column readout circuit 40 is held in a conductive state, and the second input terminal (+) of the first operational amplifier 421 is referred to. It is connected to the potential Vref.
- the second pixel signal is input to the input unit 440, and the single-ended second pixel signal pixout2 in the global shutter mode is output from the first output terminal TO1 of the input unit 440 from the first output terminal TO1.
- the voltage is supplied to the first input terminal ( ⁇ ) side of the first operational amplifier 421 to which the sampling capacitor Cs1 is connected.
- the first operational amplifier 421 reads out from the photoelectric conversion readout unit 211 of the first pixel 21, and further from the signal holding unit 212.
- a single-ended read luminance signal VSIG and a read reset signal VRST are sequentially supplied.
- the control signal AZ1 is set to the H level for a predetermined period after the read luminance signal VSIG is input.
- the auto-zero switch unit SW423 of the amplification unit 420 becomes conductive.
- the first operational amplifier 421 of the amplification unit 420 is in a reset state.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes the reference potential Vref.
- the control signal CKOS is changed from the L level to the H level for the first switch unit SW421 of the amplification unit 420 of the column readout circuit 40.
- the terminal a of the first switch unit SW421 is connected from the terminal b to the terminal c, and the connection of the first feedback capacitor Cf1 is changed from the offset potential VOS to the output of the first operational amplifier 421.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplifying unit 420 is shifted to the reference potential Vref by the offset vfs and offset shifted to the offset potential VOS.
- the output range of the first operational amplifier 421 is maintained at the same level as that in the rolling shutter mode described above.
- control signals SH and AZ2 are set to the H level for a predetermined period after the control signal CKOS is switched to the H level.
- the sample hold switch unit SW431 and the auto zero switch unit SW432 of the AD conversion unit 430 are turned on.
- the period during which the control signals SH and AZ2 are set to the H level is set longer in the order of the control signals SH and AZ2.
- the second operational amplifier 431 of the AD conversion unit 430 is reset.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 has a portion corresponding to the read luminance signal VSIG as an offset potential VOS, and is transferred to the AD conversion unit 430 through the sample hold switch unit SW431. 3 sampling capacitors Cs3 and the fourth sampling capacitor Cs4.
- the AD conversion unit 430 passes a search signal input unit 432, and the first search signal Vramp1 having a right-down slope waveform has a level-inverted slope having an inverted relationship.
- a second search signal Vramp2 having a waveform is supplied.
- the signal voltage Vcmp obtained by synthesizing the voltage held in the fourth sampling capacitor Cs4 and the search signal Vramp2 by the search signal input unit 432 is the first input of the second operational amplifier 431. Supplied to the terminal (-) side.
- the comparison output signal cmpout is output at the H level as shown in FIG. AD conversion is performed by measuring the time until the intersection with a counter (not shown).
- the amplifying unit 420 is supplied with a read reset signal VRST having a higher potential than the read luminance signal VSIG.
- the portion corresponding to the read reset signal VRST becomes a potential (VOS-G * (VRST-VSIG)) lower than the offset potential VOS by G * (VRST ⁇ VSIG) due to the offset shift.
- the control signal SH is set to the H level, and the sample hold switch section SW431 of the AD conversion section 430 becomes conductive.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes a signal (VOS-G * (VRST-VSIG)), which is transferred to the AD conversion unit 430 through the sample hold switch unit SW431. It is held in the fourth sampling capacitor Cs4.
- the AD converter 430 is supplied with the second search signal Vramp2 having a slope waveform rising to the right through the search signal input unit 432.
- the signal voltage Vcmp obtained by synthesizing the voltage held in the sampling capacitor Cs4 and the search signal Vramp2 by the search signal input unit 432 is the first input terminal ( ⁇ ) Side.
- the second operational amplifier 431 the input signal voltage Vcmp input to the first input terminal ( ⁇ ) via the third sampling capacitor Cs3 and the reference potential Vref2i supplied to the second input terminal (+) Until the reference potential Vref is crossed, the comparison output signal cmpout is output at the H level as shown in FIG. AD conversion is performed by measuring the time until the intersection with a counter (not shown).
- This comparison output signal cmpout gives the same result as in the rolling shutter mode described above.
- the difference ⁇ VSIG ⁇ VRST ⁇ between the readout reset signal VRST and the readout luminance signal VSIG is taken, and the CDS processing is performed.
- the solid-state imaging device 10 includes, from an analog signal, a pixel unit 20 in which pixels that perform photoelectric conversion are arranged, and a pixel signal read from the pixels to a vertical signal line. And a column readout circuit 40 having an AD (analog / digital) conversion function for converting into a digital signal.
- the pixel signal read from the pixel includes a first pixel signal pixout1 including a read reset signal VRST and a read luminance signal that are sequentially read from the pixel by the rolling shutter that is the first operation, and a second operation.
- the column readout circuit 40 includes an amplifier 420 that amplifies the pixel signal, and an AD converter 430 that converts the pixel signal amplified by the amplifier 420 from an analog signal to a digital signal in association with the search signal.
- the first search signal Vramp1 at the time of the first pixel signal pixout1 and the second search signal Vramp2 at the time of the second pixel signal pixout2 can be set in a relationship in which the search level is inverted.
- the column readout circuit 40 can share the readout circuit regardless of the operation mode and the signal form of the readout signal. As a result, the circuit scale is reduced, the control is facilitated, and the low Power consumption can be realized. According to the first embodiment, in particular, for a pixel capable of acquiring both a low-noise rolling shutter mode in which a reset level is output in advance and a global shutter mode pixel signal without moving object distortion, It is possible to perform processing with a small area and a low voltage without adding a sample hold circuit.
- the connection destination of the first feedback capacitor Cf1 is set to one of the output terminal of the first operational amplifier 421 and the offset potential VOS in a single-ended rolling shutter mode.
- the readout circuit can be shared regardless of the operation mode and the signal form of the readout signal. .
- the solid-state imaging device 10 includes, in the pixel unit 20, the first pixel 21 including the photoelectric conversion readout unit and the signal holding unit as the pixels, and the second including the photoelectric conversion readout unit.
- the pixel 22 is mixed, and is configured as, for example, a stacked CMOS image sensor that has both the rolling shutter function as the first operation and the global shutter function as the second operation.
- the pixel unit 20 includes a first pixel array 230 in which the photoelectric conversion readout units 211 of the plurality of first pixels 21 are arranged in a matrix, and a plurality of first pixels.
- the solid-state imaging device 10 of the first embodiment it is possible to prevent a reduction in area efficiency on the layout while preventing a complicated configuration.
- an image signal having a desired aspect ratio can be obtained according to the operation mode.
- the solid-state imaging device 10 has a stacked structure of a first substrate (upper substrate) 110 and a second substrate (lower substrate) 120.
- a first pixel array 230 is formed in which the photoelectric conversion read-out portions 211 of the first pixels 21 of the pixel unit 20 are arranged around the center thereof.
- Second pixel arrays 250-1 and 250-2 are formed on both sides (upper and lower sides) of the first vertical signal line LSGN11 in the wiring direction.
- a first vertical signal line LSGN 11 is formed on the first substrate 110.
- the signal holding units 212 of the first pixels 21 connected to the output nodes ND21 of the photoelectric conversion readout units 211 of the first pixel array 230 centering on the center are arranged in a matrix.
- the arranged holding unit array 240 (region 121) and the second vertical signal line LSGN12 are formed.
- the regions 122 and 123 for the column readout circuit 40 are formed around the holding unit array 240.
- the first substrate 110 side is basically formed of only NMOS elements, and an effective pixel region is formed by the first pixel array and the second pixel array pixel.
- FIG. 11 is a diagram illustrating a configuration example of the pixel and column readout circuit of the solid-state imaging device according to the second embodiment of the present invention.
- the solid-state imaging device 10A according to the second embodiment is different from the above-described solid-state imaging device 10 according to the first embodiment as follows.
- the first pixel signal to the column readout circuit 40A is supplied as a differential pixel signal instead of a single end in the rolling shutter mode.
- the first pixel signal pixout1 transferred through the first vertical signal line LSGN11 is supplied to the first input terminal of the first operational amplifier 421 of the amplification unit 420 via the input unit 440 of the column readout circuit 40A.
- the ( ⁇ ) side is supplied via the first sampling capacitor Cs1.
- a signal that flows on the connection line side between the current source Ibias1 and the reference potential VSS passes through the input unit 440 to the second input terminal (+) side of the first operational amplifier 421 of the amplification unit 420 and performs the second sampling. It is supplied via the capacitor Cs2.
- the third mode signal MOD3 is supplied to the input unit 440 of the column readout circuit 40A.
- the control signal CKOS is supplied at the L level to the first switch unit SW421 of the amplification unit 420 of the column readout circuit 40A.
- the first switch unit SW421 has the terminal a connected to the terminal b, and the first feedback capacitor Cf1 is connected between the first input terminal ( ⁇ ) of the first operational amplifier 421 and the output node ND421. Connected between.
- the control signal VREFSH is supplied as a clock to the second switch unit SW422 of the amplification unit 420 of the column readout circuit 40A.
- FIGS. 12A to 12K are timing charts for mainly explaining the reading operation in the column reading circuit in the differential rolling shutter mode of the solid-state imaging device according to the second embodiment.
- FIG. 12A shows the control signals SEL of the selection transistors SEL1-Tr and SEL2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22.
- FIG. 12B shows the reset signals RST1-Tr and RST2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21, the photoelectric conversion readout unit 221 of the second pixel 22, and the transfer transistor TG1-.
- the control signals TG for Tr and TG2-Tr are shown.
- FIG. 12C shows the single-ended first pixel signal pixout1 in the global shutter mode
- 12D shows the control signal AZ1 of the auto zero switch unit SW423 and the control signal VREFSH of the second switch unit SW422.
- 12E shows the control signal CKOS of the first switch unit SW421
- FIG. 12F shows the control signal SH of the sample hold switch unit SW431
- FIG. 12G shows the control of the auto zero switch unit SW432.
- Signal AZ2 is shown.
- 12H shows the output signal (amplifier output) ampout of the first operational amplifier 421
- FIG. 12I shows the first search signal Vramp1
- FIG. 12J shows the input of the second operational amplifier 431.
- the signal voltage Vcmp is shown
- FIG. 12K shows the output signal (comparison output) cmpout of the second operational amplifier 431.
- the readout operation in the pixel and column readout circuit 40A in the differential rolling shutter mode is the readout operation in the pixel and column readout circuit 40 in the single-ended rolling shutter mode described with reference to FIGS. This is the same except that the control signal VREFSH transitions in the same manner as the control signal AZ1. Therefore, the detailed operation description is omitted here.
- the signal flowing on the connection line side between the current source Ibias1 and the reference potential VSS is amplified via the input unit 440. Since it is supplied to the second input terminal (+) side of the first operational amplifier 421 of the unit 420 via the second sampling capacitor Cs2, the ground (column) for each column (column) is provided to the rolling shutter pixel. GND) Floating can be canceled, and as a result, noise such as shading can be reduced. Further, the pixel may operate in the global shutter mode.
- the second pixel signal pixout2 output from the second vertical signal line LSGN12 is supplied to the first input terminal of the first operational amplifier 421 of the amplification unit 420 via the input unit 440 of the column readout circuit 40A.
- the ( ⁇ ) side is supplied via the first sampling capacitor Cs1.
- a signal that flows on the connection line side between the current source Ibias1 and the reference potential VSS passes through the input unit 440 to the second input terminal (+) side of the first operational amplifier 421 of the amplification unit 420 and performs the second sampling. It is supplied via the capacitor Cs2.
- noise such as shading can be reduced with respect to the global shutter pixels.
- FIG. 13 is a diagram illustrating a configuration example of the first pixel of the solid-state imaging device according to the third embodiment of the present invention.
- the solid-state imaging device 10B according to the third embodiment is different from the solid-state imaging devices 10 and 10A according to the first embodiment and the second embodiment described above in that the signal holding unit 212B in the first pixel 21B is different. In the configuration.
- the signal holding unit 212B of the first pixel 21 basically includes an input unit 2121 to which the constant current source Ibias3 is connected, a sample hold unit 2122B, an output unit 2123B, nodes ND22, and ND25 to ND27. Yes.
- the constant current source Ibias3 is connected between the node ND22 and the reference potential VSS, and is controlled to be in an on state, for example, during a predetermined period during the global shutter period.
- a switch element connected between the node ND22 and the reference potential VSS and controlled to be in an on state during a predetermined period in the global shutter period may be provided.
- the sample hold unit 2122B includes switch elements SSW22 to SW24, a reset signal holding capacitor CR21, a signal holding capacitor CS21, and nodes ND25 to ND27.
- the switch element SW22 selectively connects the signal holding capacitor CS21 of the sample hold unit 2122B to the output node ND21 of the photoelectric conversion readout unit 211 via the node ND26 during the global shutter period that is the second period.
- the switch element SW22 has a terminal a connected to the input node ND22 connected to the third signal line LSGN13, and a terminal b connected to the node ND26.
- the switch element SW22 becomes conductive when the terminals a and b are connected during a period when the control signal GSHS is at a high level.
- the signal holding capacitor CS21 is connected between the node ND26 and a node ND27 connected to the reference potential VSS.
- the switch element SW23 selectively connects the reset signal holding capacitor CR21 of the sample hold unit 2122B to the output node ND21 of the photoelectric conversion readout unit 211 via the node ND25 during the global shutter period which is the second period.
- the switch element SW23 has a terminal a connected to the input node ND22 connected to the third signal line LSGN13, and a terminal b connected to the node ND25.
- the switch element SW23 becomes conductive when the terminals a and b are connected during a period when the control signal GSHR is at a high level.
- the reset signal holding capacitor CR21 is connected between the node ND25 and the node ND27 connected to the reference potential VSS.
- the switch element SW24 connects the node ND25 connected to the reset signal holding capacitor CR21 and the node ND26 connected to the signal holding capacitor CS21 during the global shutter period which is the second period.
- the switch element SW24 has a terminal a connected to the node ND26 and a terminal b connected to the node ND25.
- the switch element SW24 becomes conductive when the terminals a and b are connected during a period when the control signal CKST is at a high level. Thereby, the reset level and the signal level of the selected row are averaged.
- the switch elements SW22 to SW24 are formed by MOS transistors, for example, n-channel MOS (NMOS) transistors.
- MOS transistors for example, n-channel MOS (NMOS) transistors.
- the output unit 2123B includes a source follower transistor SF3S-Tr that basically outputs a signal held in the signal holding capacitor CS21 in accordance with the holding voltage in the global shutter period, which is the second period, and holds the held signal. It selectively outputs to the second vertical signal line LSGN12-1 driven by the constant current source Ibias1-1 through the selection transistor SEL3S-Tr.
- the source follower transistor SF3S-Tr and the selection transistor SEL3S-Tr are connected in series between the power supply potential VDD and the second vertical signal line LSGN12-1 driven by the constant current source Ibias1-1.
- a node ND26 is connected to the gate of the source follower transistor SF3S-Tr, and the selection transistor SEL3S-Tr is controlled by a control signal SEL3 applied to the gate through a control line.
- the selection transistor SEL3S-Tr is turned on when the control signal SEL3 is selected during the selection period of the H level.
- the source follower transistor SF3S-Tr outputs the column output read voltage (VRST, VSIG) corresponding to the holding voltage or the average voltage of the signal holding capacitor CS21 to the second vertical signal line LSGN12-1.
- the output unit 2123B includes a source follower transistor SF3R-Tr that basically outputs a signal held in the reset signal holding capacitor CR21 in accordance with the holding voltage in the second period, ie, the global shutter period.
- the selected signal is selectively output to the second vertical signal line LSGN12-2 driven by the constant current source Ibias1-2 through the selection transistor SEL3R-Tr.
- the source follower transistor SF3R-Tr and the selection transistor SEL3R-Tr are connected in series between the power supply potential VDD and the second vertical signal line LSGN12-2 driven by the constant current source Ibias1-2.
- a node ND25 is connected to the gate of the source follower transistor SF3R-Tr, and the selection transistor SEL3R-Tr is controlled by a control signal SEL3 applied to the gate through a control line.
- the selection transistor SEL3R-Tr is turned on when the control signal SEL3 is selected during the selection period of the H level.
- the source follower transistor SF3R-Tr outputs the column output read voltage (VRST, VSIG) corresponding to the holding voltage or the averaged voltage of the reset signal holding capacitor CR21 to the second vertical signal line LSGN12-2.
- FIGS. 14A to 14F are timing charts for mainly explaining the reading operation in the pixel section in the global shutter mode of the solid-state imaging device according to the third embodiment.
- FIGS. 15A to 15L are timing charts for mainly explaining the reading operation in the column reading circuit in the global shutter mode of the solid-state imaging device according to the third embodiment.
- FIG. 14A shows a control signal TG for the transfer transistors TG 1 -Tr of the photoelectric conversion readout unit 211 of the first pixel 21.
- FIG. 14B shows a control signal RST for the reset transistors RST 1 -Tr of the photoelectric conversion readout unit 211 of the first pixel 21.
- FIG. 14C shows the control signal GSHS of the switch element SW22 of the signal holding unit 212B of the first pixel 21.
- FIG. 14D shows the control signal GSHR of the switch element SW23 of the signal holding unit 212B of the first pixel 21.
- FIG. 14E shows the control signal CKST of the switch element SW24 of the signal holding unit 212B of the first pixel 21.
- FIG. 14F shows a control signal SEL3 for the selection transistors SEL3-Tr of the signal holding unit 212 of the first pixel 21.
- FIG. 15A shows an equivalent circuit of a pixel and column readout circuit
- FIG. 15B shows a control signal SEL3 of the selection transistors SEL3R-Tr and SEL3S-Tr of the signal holding unit 212B of the first pixel 21.
- FIG. 15C shows the control signal CKST of the switch element SW24 of the signal holding unit 212B of the first pixel 21.
- FIG. 15D shows the differential second pixel signal pixout2 in the global shutter mode
- FIG. 15E shows the control signal AZ1 of the auto zero switch unit SW423 and the control signal VREFSH of the second switch unit SW422.
- 15F shows the control signal CKOS of the first switch unit SW421, FIG.
- FIG. 15G shows the control signal SH of the sample hold switch unit SW431
- FIG. 15H shows the control of the auto zero switch unit SW432.
- Signal AZ2 is shown.
- FIG. 15I shows the output signal (amplifier output) ampout and the feedback signal ampvst of the first operational amplifier 421
- FIG. 15J shows the first search signal Vramp1
- FIG. 15K shows the second search signal Vramp1.
- the input signal voltage Vcmp of the operational amplifier 431 is shown
- FIG. 15L shows the output signal (comparison output) cmpout of the second operational amplifier 431.
- the control signals SEL of the selection transistors SEL1-Tr and SEL2-Tr of the photoelectric conversion readout unit 211 of the first pixel 21 and the photoelectric conversion readout unit 221 of the second pixel 22 are in the entire period of the global shutter mode.
- the first pixel array 230 is in an active state and is in a state in which a voltage signal from the output node ND21 can be output to the signal holding unit 212B.
- times t21 to t22 are a reset period and a charge accumulation period Tint of the photodiode PD21 and the floating diffusion FD21 in all the photoelectric conversion readout units 211 of the first pixel array 230. .
- control signals GSHS, GSHR, CKST, the selection transistors SEL3-Tr of the switch elements SW22 to SW24 that control the driving of all the signal holding units 212B of the holding unit array 240 are changed.
- the control signal SEL3 to be controlled is set to L level, the switch elements SW22 to SW24 and the selection transistor SEL3-Tr are controlled to be in a non-conductive state, and the constant current source Ibias3 is controlled to be in an off state.
- the reset transistors RST1-Tr are selected during the period when the control signal RST is at the H level and become conductive. Then, during the period when the control signal RST is at the H level, the transfer transistors TG1-Tr are selected during the period when the control signal TG is at the H level and become conductive, and the charge (electrons) accumulated by the photoelectric conversion by the photodiode PD21 is stored. The storage node becomes conductive with the floating diffusion FD21, and the photodiode PD21 and the floating diffusion FD21 are reset to the potential of the power supply voltage VDD.
- the control signal TG of the transfer transistor TG1-Tr is switched to the L level, the transfer transistor TG1-Tr is turned off, and the photodiode PD21 starts accumulating the photoelectrically converted charge.
- the control signal RST of the reset transistors RST1-Tr is held at the H level, and the floating diffusion FD21 is kept reset to the potential of the power supply voltage VDD.
- the charge of the floating diffusion FD21 is converted into a voltage signal corresponding to the amount of charge by the source follower transistor SF1-Tr, and is output as a column output read reset signal VRST.
- the read reset signal VRST output from the output node ND21 of each photoelectric conversion read unit 211 is transmitted to the corresponding signal holding unit 212B through the third signal line LSGN13, and the switch element SW23. Is held in the reset signal holding capacitor CR21. Then, the control signal GSHS of the switch element SW22 and the control signal GSHR of the switch element SW23 of the signal holding unit 212B of the first pixel 21B are switched to the L level, and the switch elements SW22 and SW23 are turned off.
- a predetermined period including time t24 is a transfer period.
- the transfer period in each photoelectric conversion readout unit 211, the transfer transistors TG1-Tr are selected when the control signal TG is at the H level and become conductive, and the charge (electrons) photoelectrically converted and accumulated by the photodiode PD21. Is transferred to the floating diffusion FD21.
- the control signal TG of the transfer transistors TG1-Tr is switched to the L level, and the transfer transistors TG1-Tr are turned off.
- the control signal TG of the transfer transistors TG1-Tr is switched to the L level, and in parallel with the timing when the transfer period ends, all the signal holding units 212B of the holding unit array 240 The following control is performed.
- the control signal GSHS is switched to the H level for a predetermined period including the time t25, the switch element SW22 is turned on, and the constant current source Ibias3 is controlled to be turned on.
- the read luminance signal VSIG output from the output node ND21 of each photoelectric conversion read unit 211 is transmitted to the corresponding signal holding unit 212 through the third signal line LSGN13, and the switch element It is held in the signal holding capacitor CS21 through SW22.
- the control signal GSHS is switched to L level, and the switch element SW22 is turned off.
- the control signal SEL3 of each selection transistor SEL3-Tr in the selected row is set to the H level, The selection transistors SEL3S-Tr and SEL3R-Tr are turned on.
- the readout luminance signal VSIG held in the signal holding capacitor CS21 and the readout reset signal VRST held in the reset signal holding capacitor CR21 are read out in parallel.
- each signal holding unit 212B the column output read luminance is determined by the source follower transistor SF3S-Tr whose gate is connected to the node ND26 according to the holding voltage of the signal holding capacitor CS21 connected to the node ND26.
- the signal VSIG is output to the second vertical signal line LSGN 12-1 and supplied to the column readout circuit 40.
- column output is read by the source follower transistor SF3R-Tr whose gate is connected to the node ND25 according to the holding voltage of the reset signal holding capacitor CR21 connected to the node ND25.
- the reset signal VRST is output to the second vertical signal line LSGN 12-2 and supplied to the column readout circuit 40.
- the control signal CKST is switched to the H level for a predetermined period including the time t27, and the switch element SW24 becomes conductive. Thereby, the reset level and the signal level of the selected row are averaged.
- the readout luminance signal VSIG held in the signal holding capacitor CS21 and the readout reset signal VRST held in the reset signal holding capacitor CR21 are averaged, and signals are read out in parallel.
- the source follower transistor SF3S-Tr whose gate is connected to the node ND26 causes the second vertical signal line as a column output average signal according to the average voltage at the node ND26. It is output to the LSGN 12-1 and supplied to the column readout circuit 40.
- the source follower transistor SF3R-Tr whose gate is connected to the node ND25 causes the second vertical signal as the column output average signal AVSR according to the average voltage at the node ND25. The signal is output to the line LSGN 12-2 and supplied to the column readout circuit 40.
- the source follower transistor SF3S-Tr for outputting a signal level V S and the reset level V R to be read from the signal holding unit 212B, when the respective offset of SF3R-Tr V OS1, V OS2 , the following relation obtained It is done.
- V OUTR (t26) ⁇ V OUTS (t26) V R + V OS2 ⁇ (V S + V OS1 )
- V OUTR (t28) ⁇ V OUTS (t28) (V R + V S ) / 2 + V OS2 ⁇ ((V R + V S ) / 2 + V OS1 )
- V OUTR (t26) ⁇ V OUTS (t26) ⁇ ⁇ V OUTR (t28) ⁇ V OUTS (t28) ⁇ V R -V S
- V OUTR (t26) is a reset signal voltage read at time t26
- V OUTS (t26) is a signal voltage read at time t26
- V OUTR (t28) is a reset signal voltage read at time t28.
- V OUTS (t28) indicates a signal voltage read at time t28.
- the offset of the source follower transistors SF3S-Tr and SF3R-Tr can be removed by subjecting the differential signal to CDS processing in the subsequent circuit.
- the readout luminance signal VSIG and readout reset signal VRST read out simultaneously and in parallel at time t26, and the average signal AVSR read out at time t28
- the second pixel signal pixout2 is supplied to the amplifying unit 420 in parallel.
- the readout luminance signal VSIG, readout reset signal VRST, and average signal AVSR of the second pixel signal pixout2 supplied simultaneously and in parallel through the input unit 440 Amplification processing and AD conversion processing are performed, and the difference between the two signals ⁇ VRST ⁇ VSIG ⁇ AVSR) ⁇ is taken to perform CDS processing.
- the fourth mode signal MOD4 is supplied to the input unit 440 of the column readout circuit 40.
- the control signal CKOS is supplied to the first switch unit SW421 of the amplification unit 420 of the column readout circuit 40 at the L level.
- the first switch unit SW421 has the terminal a connected to the terminal b, and the first feedback capacitor Cf1 is connected between the first input terminal ( ⁇ ) of the first operational amplifier 421 and the output node ND421. Connected between.
- the control signal VREFSH is supplied to the second switch unit SW422 of the amplification unit 420 of the column readout circuit 40 as a clock.
- the second pixel signal pixout2 is input to the input unit 440, and one differential second pixel signal pixout2d1 in the global shutter mode is supplied from the first output terminal TO1 of the input unit 440.
- the signal is supplied to the first input terminal ( ⁇ ) side of the first operational amplifier 421 to which the first sampling capacitor Cs1 is connected.
- the second differential pixel signal pixout2d2 in the global shutter mode is supplied from the second output terminal TO2 of the input unit 440 to the first operational amplifier to which the second sampling capacitor Cs2 is connected. 421 is supplied to the second input terminal (+) side.
- the control signal AZ1 and the control signal VREFSH are set to the H level for a predetermined period after the read luminance signal VSIG and the read reset signal VRST are input.
- the auto-zero switch unit SW423 and the switch unit SW422 of the amplification unit 420 become conductive.
- the first operational amplifier 421 of the amplification unit 420 is in a reset state.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes a predetermined DC potential, for example, the reference potential Vref.
- control signals SH and AZ2 are set to the H level for a predetermined period after the control signal AZ1 and the control signal VREFSH are switched to the L level.
- the sample hold switch unit SW431 and the auto zero switch unit SW432 of the AD conversion unit 430 are turned on.
- the period during which the control signals SH and AZ2 are set to the H level is set longer in the order of the control signals SH and AZ2.
- the second operational amplifier 431 of the AD conversion unit 430 is reset.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes the reference potential Vref and is transferred to the AD conversion unit 430 through the sample hold switch unit SW431, and the third sampling capacitor Cs3 and the fourth sampling capacitor Cs3 are output. Of the sampling capacitor Cs4.
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform that falls to the right through the search signal input unit 432.
- a signal voltage Vcmp obtained by synthesizing the voltage held in the fourth sampling capacitor Cs4 and the search signal Vramp1 by the search signal input unit 432 is the first input of the second operational amplifier 431. Supplied to terminal (-).
- the comparison output signal cmpout is output at the H level as shown in FIG. AD conversion is performed by measuring the time until the intersection with a counter (not shown).
- the amplification unit 420 is supplied with an average signal AVSR of the read luminance signal VSIG and the read reset signal VRST.
- the output signal ampout of the first operational amplifier 4211 is a level-amplified signal obtained by multiplying the difference between the read reset signal voltage VRST and the low-potential read luminance signal VSIG by the capacitance ratio multiple G on the basis of the reference potential Vref ( Vref + G * (VRST ⁇ VSIG)).
- the feedback signal ampvst is (Vref + G ′ * (VRST ⁇ VSIG)).
- the control signal SH is set to the H level, and the sample hold switch unit SW431 of the AD conversion unit 430 becomes conductive.
- the output signal (amplifier output) ampout of the first operational amplifier 421 of the amplification unit 420 becomes a signal (Vref + G * (VRST ⁇ VSIG)), which is transferred to the AD conversion unit 430 through the sample hold switch unit SW431.
- Vref + G * VRST ⁇ VSIG
- the AD converter 430 is supplied with the first search signal Vramp1 having a slope waveform that falls to the right through the search signal input unit 432.
- a signal voltage Vcmp obtained by combining the voltage held in the fourth sampling capacitor Cs4 and the search signal Vramp1 by the search signal input unit 432 is the first input of the second operational amplifier 431. Supplied to the terminal (-) side.
- the comparison output signal cmpout is output at the H level as shown in FIG. AD conversion is performed by measuring the time until the intersection with a counter (not shown).
- the difference ⁇ VRST ⁇ VSIG ⁇ AVSR) ⁇ between the readout reset signal VRST and the readout luminance signal VSIG is taken, and the digital CDS processing is performed.
- the CDS processing through the column readout circuit according to the third embodiment will be considered in association with FIGS. 15 (A) to (L).
- 15A to 15L the read luminance signal VSIG and the read reset signal VRST are read simultaneously and in parallel by the signal holding unit 212B of the first pixel 21 at time t31, and the column read circuit 40
- the signal is input to one operational amplifier 421.
- the averaged signal AVSR of the read luminance signal VSIG and the read reset signal VRST is read simultaneously and in parallel by the signal holding unit 212B of the first pixel 21 at time t32.
- the signal is input to the column readout circuit 40.
- the input signal Vinp (t31) of the second input terminal (+) of the first operational amplifier 421 at time t31 is given by the following equation.
- Vout (t31) V′ref ⁇ Qinj / Cf
- the input signal Vinp (t32) of the second input terminal (+) of the first operational amplifier 421 at time t32 is given by the following equation.
- Vinp (t32) V′ref + (Cs / (Cs + Cf)) ⁇ (Vrst ⁇ VsiG) / 2
- Vout (t32) V′ref ⁇ (Qinj / Cf) + (Cs / Cf) ⁇ (Vrst ⁇ Vsig)
- the difference between the read luminance signal VSIG and the read reset signal VRST can be output by subjecting the differential signal to CDS processing.
- the offset of the source follower transistors SF3S-Tr, SF3R-Tr, etc. can be removed by CDS processing the average signal AVSR of the read luminance signal VSIG and the read reset signal VRST.
- FIG. 16 is a circuit diagram showing a configuration example of the first operational amplifier of the column readout circuit according to the third embodiment.
- FIG. 17 is a diagram for explaining an example of control of the input range of the first operational amplifier in the differential global shutter mode.
- the first operational amplifier 421 for example, a high-gain operational amplifier with a source couple pair input as shown in FIG. 16 is applicable.
- the operational amplifier 421B in FIG. 16 includes PMOS transistors PT41 to PT44, NMOS transistors NT41 to NT44, a switch unit SW41, a current source I41, and nodes ND41 and ND42.
- the PMOS transistors PT41 and PT42 and the NMOS transistors NT41 and NT42 are connected in cascade between the power supply potential VDD and the reference potential VSS, and the PMOS transistors PT43 and PT44 and the NMOS transistors NT43 and NT44 are connected between the power supply potential VDD and the reference potential VSS. Cascade connection.
- the source of the PMOS transistor PT41 and the source of the PMOS transistor PT43 are connected to each other, and the connection node is connected to the power supply potential VDD.
- the source of the NMOS transistor PT41 and the source of the NMOS transistor PT43 are connected to each other, and the connection node is connected to the reference potential VSS and connected to the current source I41.
- a node ND41 is formed by a connection point between the drain of the PMOS transistor PT42 and the drain of the NMOS transistor NT42, and a node ND42 is formed by a connection point between the drain of the PMOS transistor PT44 and the drain of the NMOS transistor NT44.
- the node ND41 is connected to the gates of the PMOS transistors PT41 and PT43, and the node ND42 is connected to the output node ND421.
- the gates of the PMOS transistors PT42 and PT44 are commonly connected to the supply terminal Tvbp for the bias potential Vbp.
- the terminal a is commonly connected to the gates of the NMOS transistors NT42 and NT44, the terminal b is connected to the power supply potential VDD, and the terminal c is connected to the supply terminal Tvtr of the telescopic potential Vtr.
- the switch unit SW41 holds the terminal a and the terminal b in a conductive state, and holds the terminal a and the terminal c in a conductive state when the control signal CTL is at an H level.
- the first operational amplifier 421 is controlled by the switch unit SW41 so that the gates of the NMOS transistors NT42 and NT44 are connected to the power supply potential VDD, and is controlled not to function as a so-called telescopic amplifier. .
- the first operational amplifier 421 is controlled by the switch unit SW41 so that the gates of the NMOS transistors NT42 and NT44 are connected to the telescopic potential Vtr, and is controlled to function as a so-called telescopic amplifier. . This is to reduce gain error.
- the gates of the NMOS transistors NT42 and NT44 are connected to the power supply potential. Connect to VDD and do not function as a telescopic amplifier.
- the gain is high such as x4 and x8 since the input range is small, the gates of the NMOS transistors NT42 and NT44 are connected to the telescopic potential Vtr to function as a high gain telescopic amplifier. Reduce errors.
- the effects of the first and second embodiments described above can be obtained, and the differential output type global shutter pixel can be reduced without adding a capacitor or the like.
- the CDS processing of the differential output signal can be realized by the area.
- FIG. 18 is a circuit diagram showing a configuration example of a column read circuit according to the fourth embodiment of the present invention.
- 19A and 19B are diagrams for explaining a configuration example of a search signal input unit corresponding to the inverted binary search method employed in the AD conversion unit according to the fourth embodiment.
- the solid-state imaging device 10C according to the fourth embodiment is different from the solid-state imaging devices 10, 10A, and 10B according to the first, second, and third embodiments described above in that the AD conversion unit 430C in the column readout circuit 40 is used.
- the search signal input unit 432C has a configuration.
- the first mode signal MOD1 (single-ended rolling shutter mode), the third mode signal MOD3 (differential rolling shutter mode), the fourth mode In the case of the signal MOD4 (differential global shutter mode)
- the first search signal Vramp1 is supplied to the search signal input unit 432.
- the second search signal Vramp2 is supplied to the search signal input unit 432 in the case of the second mode signal MOD2 (single-ended global shutter mode).
- the AD converter 430 employs the first search signal Vramp1 and the second search signal Vramp2 whose levels are inverted.
- the AD conversion unit 430C is configured as a SAR type (successive comparison type) ADC, and an inverted binary search is employed for supplying a search signal.
- the search signal input unit 432C includes a plurality (x) of fourth sampling capacitors Cs4-1 to Cs4-x and a plurality of switch units SW432-1 to SW432-x.
- the fourth sampling capacitors Cs4-1 to Cs4-x one electrode (terminal) is connected in common to the input node ND431 of the AD conversion unit 430C, and the other electrode (terminal) is a switch arranged correspondingly.
- the terminals SW432-1 to SW432-x are connected to the terminal a.
- the terminals b of the switch units SW432-1 to SW432-x are connected to the reference potential Vref, and the terminal c is connected to the ground GND.
- the switch units SW432-1 to SW432-x are controlled by the control signal CTR.
- the SAR controls the reference potential Vref and the ground GND to alternately switch in this order.
- the switch units SW432-1 to SW432-x are connected to the control signal CTR.
- the first pixel signal pixout1 read in the order of the read reset signal VRST and the read luminance signal VSIG is AD. Can be converted.
- the switch units SW432-1 to SW432-x are controlled by the control signal CTR.
- the SAR controls the ground GND and the reference potential Vref to switch alternately in this order.
- the switch units SW432-1 to SW432-x are connected to the control signal CTR.
- the solid-state imaging devices 10, 10A to 10C described above can be applied as imaging devices to electronic devices such as digital cameras, video cameras, portable terminals, surveillance cameras, and medical endoscope cameras.
- FIG. 20 is a diagram illustrating an example of a configuration of an electronic device equipped with a camera system to which the solid-state imaging device according to the embodiment of the present invention is applied.
- the electronic apparatus 300 includes a CMOS image sensor 310 to which the solid-state imaging devices 10 and 10A to 10C according to the present embodiment can be applied. Furthermore, the electronic apparatus 300 includes an optical system (lens or the like) 320 that guides incident light (forms a subject image) to the pixel region of the CMOS image sensor 310.
- the electronic device 320 includes a signal processing circuit (PRC) 330 that processes an output signal of the CMOS image sensor 310.
- PRC signal processing circuit
- the signal processing circuit 330 performs predetermined signal processing on the output signal of the CMOS image sensor 310.
- the image signal processed by the signal processing circuit 330 can be displayed as a moving image on a monitor composed of a liquid crystal display or the like, or output to a printer, or directly recorded on a recording medium such as a memory card. Is possible.
- CMOS image sensor 310 As described above, by mounting the above-described solid-state imaging devices 10 and 10A to 10C as the CMOS image sensor 310, it is possible to provide a camera system with high performance, small size, and low cost. Electronic devices such as surveillance cameras and medical endoscope cameras are used for applications where the camera installation requirements include restrictions such as mounting size, number of connectable cables, cable length, and installation height. Can be realized.
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Abstract
Description
CMOSイメージセンサは、デジタルカメラ、ビデオカメラ、監視カメラ、医療用内視鏡、パーソナルコンピュータ(PC)、携帯電話等の携帯端末装置(モバイル機器)等の各種電子機器の一部として広く適用されている。
この順次走査、すなわち、電子シャッタとしてローリングシャッタを採用した場合は、光電荷を蓄積する露光の開始時間、および終了時間を全ての画素で一致させることができない。そのため、順次走査の場合、動被写体の撮像時に撮像画像に歪みが生じるという問題がある。
グローバルシャッタを採用したCMOSイメージセンサでは、フォトダイオードから電荷を電圧信号として一斉に信号保持部の信号保持キャパシタに蓄積し、そののち順次読み出すことにより、画像全体の同時性を確保している(たとえば、非特許文献1参照)。
また、このCMOSイメージセンサは、光電変換読み出し部の出力を、信号保持部をバイパスして信号線に転送するバイパススイッチを有しており、グローバルシャッタ機能に加えてローリングシャッタ機能を併せ持つように構成されている。
このカラム読み出し回路は、ローリングシャッタ機能に対応した構成を有しており、カラムアンプ、相関二重サンプリング(CDS:Correlated Double Sampling)回路、およびアナログデジタル変換器(ADC)を含んで構成されている。
一方、グローバルシャッタモード時は、画素から読み出し輝度信号および読み出しリセット信号の順に読み出されてカラム読み出し回路で処理される。
そのため、ローリングシャッタ機能とグローバルシャッタ機能でカラム読み出し回路が別構成とせざるを得ないのが現状である。
同様に、ローリングシャッタ機能とグローバルシャッタ機能を備えるCMOSイメージセンサにおいても、カラム読み出し回路を共用することが困難であり、モードに応じたカラム読み出し回路を個別に設ける必要があり、回路規模の増大や制御の複雑化を招く等の不利益がある。
図1は、本発明の第1の実施形態に係る固体撮像装置の構成例を示すブロック図である。
本実施形態において、固体撮像装置10は、たとえばCMOSイメージセンサにより構成される。
これらの構成要素のうち、たとえば垂直走査回路30、読み出し回路40、水平走査回路50、およびタイミング制御回路60により画素信号の読み出し部70が構成される。
本第1の実施形態に係る固体撮像装置10において、画素部20は、複数の第1の画素の光電変換読み出し部が行列状に配置された第1の画素アレイと、複数の第1の画素の信号保持部が行列状に配置された保持部アレイと、複数の第2の画素の光電変換読み出し部が行列状に配置された第2の画素アレイと、を含んで構成されている。
そして、第1の動作であるローリングシャッタモード時に、第1の画素および第2の画素の光電変換読み出し部の読み出し信号が第1の垂直信号線にバイパス経路をたどることなく直ちに出力される。
また、第2の動作であるグローバルシャッタモード時に、第1の画素の信号保持部の保持信号が第2の垂直信号線に出力される。
本第1の実施形態に係る固体撮像装置10において、カラム読み出し回路40は、後で詳述するように、動作モードや読み出し信号の信号形態(シングルエンドや差動等の信号)にかかわらず一つの回路構成で共用することが可能に形成されている。
図2は、本発明の第1の実施形態に係る固体撮像装置10の第1の画素および第2の画素の一例を示す回路図である。
画素部20に配置される第2の画素22は、光電変換読み出し部221を含んで構成されている。
具体的には、この光電変換読み出し部211は、たとえば光電変換素子であるフォトダイオードPD21を有する。
このフォトダイオードPD21に対して、転送素子としての転送トランジスタTG1-Tr、リセット素子としてのリセットトランジスタRST1-Tr、ソースフォロワ素子としてのソースフォロワトランジスタSF1-Tr、出力ノードND21、および選択素子(選択スイッチ)としての選択トランジスタSEL1-Trをそれぞれ一つずつ有する。
このように、第1の実施形態に係る第1の画素21の光電変換読み出し部211は、転送トランジスタTG1-Tr、リセットトランジスタRST1-Tr、ソースフォロワトランジスタSF1-Tr、および選択トランジスタSEL1-Trの4トランジスタ(4Tr)を含んで構成されている。
光電変換読み出し部211は、ローリングシャッタモード時に第1の画素信号pixout1である読み出しリセット信号(信号電圧)(VRST1)および読み出し輝度信号(信号電圧)(VSIG1)を第1の垂直信号線LSGN11に出力する。
光電変換読み出し部211は、グローバルシャッタモード時に第2の画素信号pxout2である読み出し輝度信号(信号電圧)(VSIG1)および読み出しリセット信号(信号電圧)(VRST1)を信号保持部212に出力する。
定電流源Ibias1は、ローリングシャッタモード時とグローバルシャッタモード時とで共用される。
定電流源Ibias1は、図2に示すように、スイッチ部410により動作モードに応じて接続先が切り替えられる。ローリングシャッタモード時には、第1の垂直信号線LSGN11が定電流源Ibias1に接続され、第2の垂直信号線LSGN12が基準電位VSS(たとえばグランド)に接続される。一方、グローバルシャッタモード時には、第2の垂直信号線LSGN12が定電流源Ibias1に接続され、第1の垂直信号線LSGN11が基準電位VSS(たとえばグランド)に接続される。
以下、信号電荷は電子であり、各トランジスタがn型トランジスタである場合について説明するが、信号電荷が正孔(ホール)であったり、各トランジスタがp型トランジスタであっても構わない。
また、本実施形態は、複数のフォトダイオードおよび転送トランジスタ間で、各トランジスタを共有している場合にも有効である。
転送トランジスタTG1-Trは、制御信号TGがハイ(H)レベルの転送期間に選択されて導通状態となり、フォトダイオードPD21で光電変換され蓄積された電荷(電子)をフローティングディフュージョンFD21に転送する。
リセットトランジスタRST1-Trは、制御信号RSTがHレベルのリセット期間に選択されて導通状態となり、フローティングディフュージョンFD21を電源電圧VDDの電位にリセットする。
ソースフォロワトランジスタSF1-Trのソースと選択トランジスタSEL1-Trのドレインとの接続点により出力ノードND21が形成されている。
この出力ノードND21と信号保持部212の入力部間の信号線LSGN13は、たとえば信号保持部212の入力部に配置された定電流源Ibias3により駆動される。
ソースフォロワトランジスタSF1-TrはフローティングディフュージョンFD21の電荷を電荷量に応じた電圧信号に変換した列出力の読み出しリセット信号(VRST1)および読み出し輝度信号(VSIG1)または読み出し輝度信号(VSIG1)および読み出しリセット信号(VRST1)を出力ノードND21に出力する。
選択トランジスタSEL1-Trは、制御信号SELがHレベルの選択期間に選択されて導通状態となる。これにより、ソースフォロワトランジスタSF1-TrはフローティングディフュージョンFD21の電荷を電荷量に応じた電圧信号に変換した読み出しリセット信号(VRST1)および読み出し輝度信号(VSIG1)を第1の垂直信号線LSGN11に出力する。
スイッチ素子SW21の端子aが第3の信号線LSGN13に接続された入力ノードND22と接続され、端子bがサンプルホールド部2122側と接続されたノードND23に接続されている。
スイッチ素子SW21は、たとえば信号sw1がハイレベルの期間に端子aとbが接続されて導通状態となる。
信号保持キャパシタC21は、ノードND23とノードND24との間に接続されている。
信号保持キャパシタC22は、ノードND24と基準電位VSSとの間に接続されている。
リセットトランジスタRST3-Trは、制御信号RST3がHレベルのリセット期間に選択されて導通状態となり、ノードND24(およびキャパシタC21、C22)を電源電圧VDDの電位にリセットする。
選択トランジスタSEL3-Trは、制御信号SEL3がHレベルの選択期間に選択されて導通状態となる。これにより、ソースフォロワトランジスタSF3-Trは信号保持キャパシタC21、C22の保持電圧に応じた列出力の読み出し電圧(VRST,VSIG)を第2の垂直信号線LSGN12に出力する。
第2の画素22の光電変換読み出し部221は、上述した第1の画素21の光電変換読み出し部211と同様の構成を有する。
具体的には、この光電変換読み出し部221は、たとえば光電変換素子であるフォトダイオードPD22を有する。
このフォトダイオードPD22に対して、転送素子としての転送トランジスタTG2-Tr、リセット素子としてのリセットトランジスタRST2-Tr、ソースフォロワ素子としてのソースフォロワトランジスタSF2-Tr、および選択素子(選択スイッチ)としての選択トランジスタSEL2-Trをそれぞれ一つずつ有する。
このように、第1の実施形態に係る第2の画素22の光電変換読み出し部221は、転送トランジスタTG2-Tr、リセットトランジスタRST2-Tr、ソースフォロワトランジスタSF2-Tr、および選択トランジスタSEL2-Trの4トランジスタ(4Tr)を含んで構成されている。
信号電荷は電子であり、各トランジスタがn型トランジスタである場合について説明するが、信号電荷が正孔(ホール)であったり、各トランジスタがp型トランジスタであっても構わない。
また、本実施形態は、複数のフォトダイオードと転送トランジスタ間で、各トランジスタを共有している場合にも有効である。
転送トランジスタTG2-Trは、制御信号TGがHレベルの転送期間に選択されて導通状態となり、フォトダイオードPD22で光電変換され蓄積された電荷(電子)をフローティングディフュージョンFD22に転送する。
リセットトランジスタRST2-Trは、制御信号RSTがHレベルのリセット期間に選択されて導通状態となり、フローティングディフュージョンFD22を電源電圧VDDの電位にリセットする。
選択トランジスタSEL2-Trは、制御信号SELがHレベルの選択期間に選択されて導通状態となる。これにより、ソースフォロワトランジスタSF2-TrはフローティングディフュージョンFD22の電荷を電荷量に応じた電圧信号に変換した列出力の読み出しリセット信号(VRST2)および読み出し輝度信号(VSIG2)を第1の垂直信号線LSGN11に出力する。
第1の画素アレイ230は、たとえば16:9のアスペクト比の画像が出力可能なように、複数の第1の画素21の光電変換読み出し部211がN行×M列の2次元の行列状(マトリクス状)に配列されている。
保持部アレイ240は、第1の画素アレイ230と同様に、たとえば16:9のアスペクト比の画像が出力可能なように、複数の第1の画素21の信号保持部212がN行×M列の2次元の行列状(マトリクス状)に配列されている。
また、垂直走査回路30は、アドレス信号に従い、信号の読み出しを行うリード行と、フォトダイオードPDに蓄積された電荷をリセットするシャッタ行の行アドレスの行選択信号を出力する。
カラム読み出し回路40は、第1の動作であるローリングシャッタモード時に、第1の垂直信号線LSGN11に、第1の画素21の光電変換読み出し部211および第2の画素22の光電変換読み出し部221から読み出された第1の画素信号pixout1(VSL1)、並びに、第2の動作であるグローバルシャッタモード時に、第2の垂直信号線LSGN12に、第1の画素21の信号保持部212から読み出された第2の画素信号pixout2(VSL2)に対して、増幅処理およびAD変換処理を行う。
第2の画素信号pixout2(VSL2)は、第2の動作であるグローバルシャッタモード時に画素(本例では第1の画素21の光電変換読み出し部211、さらに信号保持部212)から順に読み出される読み出し輝度信号VSIGおよび読み出しリセット信号VRSTを含む画素読み出し信号をいう。
カラム読み出し回路40は、図5に関連付けて説明するように、第1の画素信号pixout1(VSL1)および第2の画素信号pixout2(VSL2)を増幅する増幅部420、並びに、増幅部420で増幅された画素部20の各列出力のアナログ読み出し信号VSL1、VSL2をデジタル信号に変換するAD変換器を含むAD変換部430により構成されている。
また、カラム読み出し回路40は、入力段にモード信号MODx(x=1,2,3,4,・・)に応じて画素の読み出し信号pixoutを、増幅部420に配置される演算増幅器の2つの入力端子に選択的に入力させる入力部440が配置されている。
第1のオペアンプ421の出力端子は、出力ノードND421に接続されている。
第1のモード信号MOD1のときは、ローリングシャッタモード時のシングルエンドの第1の画素信号pixout1が、入力部440の第1の出力端子TO1から供給される。
第2のモード信号MOD2のときは、グローバルシャッタモード時のシングルエンドの第2の画素信号pixout2が、入力部440の第1の出力端子TO1から供給される。
第3のモード信号MOD3のときは、差動ローリングシャッタモード時の差動信号のうちの一方の第1の画素信号pixout1d1が、入力部440の第1の出力端子TO1から供給される。
第4のモード信号MOD4のときは、差動グローバルシャッタモード時の差動信号のうちの一方の第2の画素信号pixout2d1が、入力部440の第1の出力端子TO1から供給される。
第1のモード信号MOD1のときは、画素信号は入力部440の第2の出力端子TO2から供給されない。
第2のモード信号MOD2のときは、画素信号は入力部440の第2の出力端子TO2から供給されない。
第3のモード信号MOD3のときは、差動ローリングシャッタモード時の差動信号のうちの他方の第1の画素信号pixout1d2が、入力部440の第2の出力端子TO2から供給される。
第4のモード信号MOD4のときは、差動グローバルシャッタモード時の差動信号のうちの他方の第2の画素信号pixout2d2が、入力部440の第2の出力端子TO2から供給される。
第1のスイッチ部SW421は、たとえば制御信号CKOSがローレベル(L)のときは端子aを端子bと接続し、制御信号CKOSがハイレベル(H)のときは端子aを端子cと接続する。
すなわち、第1の帰還キャパシタCf1は、入力部440に供給されるモード信号が、第1のモード信号MOD1(シングルエンドのローリングシャッタモード)、第3のモード信号MOD3(差動のローリングシャッタモード)、および第4のモード信号MOD4(差動のグローバルシャッタモード)のとき、第1のオペアンプ421の第1の入力端子(-)と出力ノードND421との間に接続される。
第1の帰還キャパシタCf1は、入力部440に供給されるモード信号が、第2のモード信号MOD2(シングルエンドのグローバルシャッタモード)のとき、第1のオペアンプ421の第1の入力端子(-)は、出力ノードND421と接続される状態と、オフセット電位VOSとの間に接続される状態を遷移する。
第2のスイッチ部SW422は、制御信号VREFSHがクロックとして供給され、クロックがHレベルのとき端子aと端子bが導通状態(オン状態)に保持され、Lレベルのとき端子aと端子bは非導通状態(オフ状態)に保持される。
第2のスイッチ部SW422は、入力部440に供給されるモード信号が、第1のモード信号MOD1(シングルエンドのローリングシャッタモード)、第2のモード信号MOD2(シングルエンドのグローバルシャッタモード)のとき、端子aと端子bが導通状態(オン状態)に保持され、第3のモード信号MOD3(差動のローリングシャッタモード)、第4のモード信号MOD4(差動のグローバルシャッタモード)のとき、導通状態(オン状態)と非導通状態(オフ状態)を遷移される。
オートゼロスイッチ部SW423は、制御信号AZ1がHレベルのとき端子aと端子bが導通状態(オン状態)に保持され、Lレベルのとき端子aと端子bは非導通状態(オフ状態)に保持される。
第1のオペアンプ421は、オートゼロスイッチ部SW423が導通状態のとき、リセット状態となる。
第2のオペアンプ431の第1の入力端子(-)に供給される入力信号電圧Vcmpは、AD変換中には、第3のサンプリングキャパシタCs3に保持された電圧、第4のサンプリングキャパシタCs4に保持された電圧、および探索信号入力部432による探索信号Vrampを合成した信号電圧である。
本例では、探索信号Vrampとしては、たとえば図5中の第1の探索信号Vramp1のように左側がレベルが高く右側がレベルが低い右下がりのスロープ波形として供給される。
また、本例では、探索信号Vrampとしては、たとえば図5中の第2の探索信号Vramp2のように左側がレベルが低く右側がレベルが高い右上がりのスロープ波形として供給される。
第1の探索信号Vramp1と第2の探索信号Vramp2は、探索レベル、ここではスロープ波形のレベルが反転した関係にある。
一方、本実施形態において、探索信号Vrampとして、入力部440に供給されるモード信号が、第2のモード信号MOD2(シングルエンドのグローバルシャッタモード)のとき第2の探索信号Vramp2が探索信号入力部432に供給される。
第4のサンプリングキャパシタCs4は、入力ノードND431と探索信号Vrampの供給ラインとの間に接続されている。
このように、第2のオペアンプ431は、比較器として機能する。
サンプルホールドスイッチ部SW431は、たとえば制御信号SHがHレベルのとき端子aと端子bが導通状態(オン状態)に保持され、Lレベルのとき端子aと端子bは非導通状態(オフ状態)に保持される。
AD変換部430は、サンプルホールドスイッチ部SW431が導通状態のときに、増幅部420のアンプ出力ampoutを入力ノードND431に入力させる。
オートゼロスイッチ部SW432は、制御信号AZ2がHレベルのとき端子aと端子bが導通状態(オン状態)に保持され、Lレベルのとき端子aと端子bは非導通状態(オフ状態)に保持される。
第2のオペアンプ431は、オートゼロスイッチ部SW432が導通状態のとき、リセット状態となる。
このとき、AD変換部430には、探索信号入力部432を通して右下がりのスロープ波形の第1の探索信号Vramp1が供給される。
このとき、AD変換部430には、探索信号入力部432を通して第1の探索信号Vramp1とはレベルが反転した関係にある右上がりのスロープ波形の第2の探索信号Vramp2が供給される。
このとき、AD変換部430には、探索信号入力部432を通して右下がりのスロープ波形の第1の探索信号Vramp1が供給される。
このとき、AD変換部430には、探索信号入力部432を通して右下がりのスロープ波形の第1の探索信号Vramp1が供給される。
ただし、本第1の実施形態において、画素部20は第1のモード信号MOD1および第2のモード信号MOD2に応じた画素信号を生成するように構成されている。
したがって、本第1の実施形態のカラム読み出し回路40は、第1のモード信号MOD1に応じたローリングシャッタモード時のシングルエンドの第1の画素信号pixout1(VSL1)、および第2のモード信号MOD2に応じたグローバルシャッタモード時のシングルエンドの第2の画素信号pixout2(VSL2)を処理することになる。
次に、本第1の実施形態に係る固体撮像装置10の積層構造について説明する。
固体撮像装置10は、たとえばウェハレベルで貼り合わせた後、ダイシングで切り出した積層構造の撮像装置として形成される。
本例では、第2の基板120上に第1の基板110が積層された構造を有する。
また、第1の基板110には、第1の垂直信号線LSGN11が形成されている。
そして、保持部アレイ240の周囲、図6の例では、図中の上側および下側にカラム読み出し回路40用の領域122,123が形成されている。なお、カラム読み出し回路40は、保持部アレイ240の領域121の上側および下側のいずれかに配置されるように構成してもよい。
また、保持部アレイ240の側部側に垂直走査回路30用の領域124や、デジタル系や出力系の領域125が形成されている。
また、第2の基板120には、垂直走査回路30、水平走査回路50、およびタイミング制御回路60も形成されてもよい。
また、第1の基板110の第1の垂直信号線LSGN11と第2の基板120のカラム読み出し回路40の入力部とが、たとえば図2に示すように、それぞれビア(Die-to-Die Via)やマイクロバンプ等を用いて電気的な接続が行われている。
以上、固体撮像装置10の各部の特徴的な構成および機能について説明した。
次に、本第1の実施形態に係る固体撮像装置10のローリングシャッタモード時のシングルエンドの第1の画素信号およびグローバルシャッタモード時のシングルエンドの第2の画素信号の読み出し動作等について詳述する。
次に、ローリングシャッタモード時の読み出し動作について説明する。
図7(A)~(D)は、本第1の実施形態に係る固体撮像装置のローリングシャッタモード時の主として画素部における読み出し動作を説明するためのタイミングチャートである。
図8(A)~(L)は、本第1の実施形態に係る固体撮像装置のローリングシャッタモード時の主としてカラム読み出し回路における読み出し動作を説明するためのタイミングチャートである。
図7(D)は第1の画素21の信号保持部212のスイッチ素子SW21の制御信号sw1、選択トランジスタSEL3-Trの制御信号SEL3を示している。
図8(D)はローリングシャッタモード時のシングルエンドの第1の画素信号pixout1を示し、図8(E)はオートゼロスイッチ部SW423の制御信号AZ1を示し、図8(F)は第1のスイッチ部SW421の制御信号CKOSを示し、図8(G)はサンプルホールドスイッチ部SW431の制御信号SHを示し、図8(H)はオートゼロスイッチ部SW432の制御信号AZ2を示している。
図8(I)は第1のオペアンプ421の出力信号(アンプ出力)ampoutを示し、図8(J)は第1の探索信号Vramp1を示し、図8(K)は第2のオペアンプ431の入力信号(信号電圧)Vcmpを示し、図8(L)は第2のオペアンプ431の出力信号(比較出力)cmpoutを示している。
ローリングシャッタモード期間においては、第1の基板110に形成されただ第1の画素アレイ230および第2の画素アレイ250-1,250-2が行単位で順次にアクセスされる。
このリセット期間PRが経過した後(リセットトランジスタRST2-TrまたはRST1-Trが非導通状態)、転送期間PTが開始されるまでの時刻t1を含む期間が、リセット状態時の画素信号を読み出す第1読み出し期間となる。
転送期間PTに転送トランジスタTG2-Tr(またはTG1-Tr)が、制御信号TGがハイレベル(H)の期間に選択されて導通状態となり、フォトダイオードPD22(またはPD21)で光電変換され蓄積された電荷(電子)がフローティングディフュージョンFD22(またはFD21)に転送される。
この転送期間PTが経過した後(転送トランジスタTG2-TrまたはTG1-Trが非導通状態)、フォトダイオードPD22(またはPD21)が光電変換して蓄積した電荷に応じた画素信号を読み出す時刻t2を含む第2読み出し期間となる。
また、ローリングシャッタモード期間において、カラム読み出し回路40の増幅部420の第1のスイッチ部SW421に対して制御信号CKOSがLレベルで供給される。これにより、第1のスイッチ部SW421は、端子aを端子bとが接続されて、第1の帰還キャパシタCf1は、第1のオペアンプ421の第1の入力端子(-)と出力ノードND421との間に接続される。
また、ローリングシャッタモード期間において、カラム読み出し回路40の増幅部420の第2のスイッチ部SW422は、導通状態に保持され、第1のオペアンプ421の第2の入力端子(+)が参照電位Vrefに接続されている。
第1のオペアンプ421の第1の入力端子(-)側には、図8(D)に示すように、第1の画素21の光電変換読み出し部211および第2の画素22の光電変換読み出し部221から順に読み出されるシングルエンドの読み出しリセット信号VRST、読み出し輝度信号VSIGが順に供給される。
制御信号AZ1、SH、およびAZ2がHレベルに設定される期間としては、制御信号SH、AZ2,AZ1の順で長く設定される。
これにより、増幅部420の第1のオペアンプ421、およびAD変換部430の第2のオペアンプ431がリセット状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、参照電位Vrefとなり、サンプルホールドスイッチ部SW431を通してAD変換部430に転送され、第3のサンプリングキャパシタCs3と第4のサンプリングキャパシタCs4に保持される。
そして、図8(K)に示すように、第4のサンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp1を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)側に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2とが比較され、参照電位Vref2と交差するまでの間、図8(L)に示すように、比較出力信号cmpoutがHレベルで出力される。このHレベル期間を図示しないカウンタに保持することで、AD変換を行う。
そして、第1のオペアンプ421の出力信号ampoutは、参照電位Vrefを基準に、読み出しリセット信号VRSTと低電位の読み出し輝度信号VSIGの差分に容量比倍Gを掛け合わせたレベル増幅された信号(Vref+G*(VRST-VSIG))となる。
そして、転送期間後の所定期間、図8(G)に示すように、制御信号SHがHレベルに設定され、AD変換部430のサンプルホールドスイッチ部SW431が導通状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、信号(Vref+G*(VRST-VSIG))となり、サンプルホールドスイッチ部SW431を通してAD変換部430に転送され、第4のサンプリングキャパシタCs4に保持される。
そして、図8(K)に示すように、第4のサンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp1を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)側に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2とが比較され、参照電位Vref2と交差するまでの間、図8(L)に示すように、比較出力信号cmpoutがHレベルで出力される。このHレベル期間を図示しないカウンタに保持することで、AD変換を行う。
次に、グローバルシャッタモード時の読み出し動作について説明する。
図9(A)~(G)は、本第1の実施形態に係る固体撮像装置のグローバルシャッタモード時の主として画素部における読み出し動作を説明するためのタイミングチャートである。
図10(A)~(L)は、本第1の実施形態に係る固体撮像装置のグローバルシャッタモード時の主としてカラム読み出し回路における読み出し動作を説明するためのタイミングチャートである。
図9(D)は第1の画素21の信号保持部212のスイッチ素子SW21の制御信号sw1を示している。図9(E)は第1の画素21の信号保持部212のリッセットトランジスタRST3-Trの制御信号RST3を示している。図9(F)は第1の画素21の信号保持部212の選択トランジスタSEL3-Trの制御信号SEL3を示している。図9(G)は第1の画素21の信号保持部212に配置された定電流源Ibias3の駆動状態(オン、オフ状態)を示している。
図10(D)はグローバルシャッタモード時のシングルエンドの第2の画素信号pixout2を示し、図10(E)はオートゼロスイッチ部SW423の制御信号AZ1を示し、図10(F)は第1のスイッチ部SW421の制御信号CKOSを示し、図10(G)はサンプルホールドスイッチ部SW431の制御信号SHを示し、図10(H)はオートゼロスイッチ部SW432の制御信号AZ2を示している。
図10(I)は第1のオペアンプ421の出力信号(アンプ出力)ampoutを示し、図10(J)は第2の探索信号Vramp2を示し、図10(K)は第2のオペアンプ421の入力信号電圧Vcmpを示し、図10(L)は第2のオペアンプ431の出力信号(比較出力)cmpoutを示している。
これにより、グローバルシャッタモードの全期間中第1の画素アレイ230と第2の画素アレイ250-1,250-2から第1の垂直信号線LSGN11への電圧信号の出力が抑止(停止)される。
したがって、第2の画素アレイ250-1,250-2は非アクティブ状態に制御される。
また、第1の画素アレイ230は、アクティブ状態であり、出力ノードND21からの電圧信号の信号保持部212への出力可能状態となっている。
そして、制御信号RSTがHレベル期間中に、転送トランジスタTG1-Trが、制御信号TGがHレベルの期間に選択されて導通状態となり、フォトダイオードPD21で光電変換され蓄積された電荷(電子)の蓄積ノードがフローティングディフュージョンFD21と導通状態となり、フォトダイオードPD21およびフローティングディフュージョンFD21が電源電圧VDDの電位にリセットされる。
このとき、リセットトランジスタRST1-Trの制御信号RSTはHレベルに保持されており、フローティングディフュージョンFD21が電源電圧VDDの電位にリセットされたままの状態に保持される。
そして、リセット期間の終了のため、時刻t12の前に、リセットトランジスタRST1-Trの制御信号RSTはLレベルに切り替えられ、リセットトランジスタRST1-Trは非導通状態となる。
このリセット期間PRが経過した後(リセットトランジスタRST1-Trが非導通状態)、転送期間PTが開始されるまでの時刻t12を含む期間が、リセット状態時の画素信号を読み出す第1読み出し期間となる。
また、時刻t12,t13、t14を含む所定期間、スイッチ素子SW21の制御信号sw1がHレベルに保持され、スイッチ素子SW21がオン状態(導通状態)に保持される。
同様に、時刻t12,t13、t14を含む所定期間、定電流源Ibias3がオン状態に制御される。
なお、定電流源Ibias3は、時刻t14を経過し、スイッチ素子SW21の制御信号sw1がLレベルに切り替えられスイッチ素子SW21がオフ状態(非導通状態)となった後に、オフ状態に制御される。
転送期間PTに転送トランジスタTG1-Trが、制御信号TGがハイレベル(H)の期間に選択されて導通状態となり、フォトダイオードPD21で光電変換され蓄積された電荷(電子)がフローティングディフュージョンFD21に転送される。
この転送期間PTが経過した後(転送トランジスタTG1-Trが非導通状態)、フォトダイオードPD2)が光電変換して蓄積した電荷に応じた画素信号を読み出す時刻t14を含む第2読み出し期間となる。
そして、時刻t15において、信号保持キャパシタC21およびC22に保持された保持信号VSIG(VSIG-VRST)の読み出しが行われる。
このとき、各信号保持部212においては、ゲートがノードND24に接続されたソースフォロワトランジスタSF3-Trにより、ノードND24に接続された信号保持キャパシタC21およびC22の保持電圧に応じて、列出力の読み出し輝度信号(VSIG-VRST)として第2の垂直信号線LSGN12に出力され、カラム読み出し回路40に供給される。
そして、時刻t16を含む所定期間において、ノードND24に接続された信号保持キャパシタC21およびC22に保持されたリセット保持信号(VRST)の読み出しが行われる。
このとき、各信号保持部212においては、ゲートがノードND24に接続されたソースフォロワトランジスタSF3-Trにより、ノードND24に接続された信号保持キャパシタC21およびC22の保持電圧に応じて、列出力の読み出しリセット信号(VRST)として第2の垂直信号線LSGN12に出力され、カラム読み出し回路40に供給される。
また、シングルエンドのグローバルシャッタモード期間において、カラム読み出し回路40の増幅部420の第2のスイッチ部SW422は、導通状態に保持され、第1のオペアンプ421の第2の入力端子(+)が参照電位Vrefに接続されている。
第1のオペアンプ421の第1の入力端子(-)側には、図10(D)に示すように、第1の画素21の光電変換読み出し部211から読み出され、さらに信号保持部212から順に読み出されるシングルエンドの読み出し輝度信号VSIG、読み出しリセット信号VRSTが順に供給される。
これにより、増幅部420の第1のオペアンプ421がリセット状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、参照電位Vrefとなる。
これにより、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、参照電位Vrefにオフセットvfs分シフトされ、オフセット電位VOSにオフセットシフトされる。
このオフセットシフトにより、第1のオペアンプ421の出力レンジは、上述したローリングシャッタモード時と同じレベルに維持される。
制御信号SHおよびAZ2がHレベルに設定される期間としては、制御信号SH、AZ2の順で長く設定される。
これにより、AD変換部430の第2のオペアンプ431がリセット状態となる。
そして、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、読み出し輝度信号VSIGに対応する部分はオフセット電位VOSとなり、サンプルホールドスイッチ部SW431を通してAD変換部430に転送され、第3のサンプリングキャパシタCs3および第4のサンプリングキャパシタCs4に保持される。
そして、図8(K)に示すように、第4のサンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp2を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)側に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2iとが比較され、参照電位Vref2iと交差するまでの間、図10(L)に示すように、比較出力信号cmpoutがHレベルで出力される。この交差するまでの時間を図示しないカウンタで測定することにより、AD変換が行われる。
読み出しリセット信号VRSTに対応する部分は、オフセットシフトによりオフセット電位VOSよりG*(VRST-VSIG)だけ低い電位(VOS-G*(VRST-VSIG))となる。
そして、転送期間後の所定期間、図10(G)に示すように、制御信号SHがHレベルに設定され、AD変換部430のサンプルホールドスイッチ部SW431が導通状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、信号(VOS-G*(VRST-VSIG))となり、サンプルホールドスイッチ部SW431を通してAD変換部430に転送され、第4のサンプリングキャパシタCs4に保持される。
そして、図10(K)に示すように、サンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp2を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)側に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2iとが比較され、参照電位Vrefと交差するまでの間、図10(L)に示すように、比較出力信号cmpoutがHレベルで出力される。この交差するまでの時間を図示しないカウンタで測定することにより、AD変換が行われる。
固体撮像装置10において、画素から読み出される画素信号は、第1の動作であるローリングシャッタにより画素から順に読み出される読み出しリセット信号VRSTおよび読み出し輝度信号を含む第1の画素信号pixout1と、第2の動作であるグローバルシャッタにより画素から順に読み出される読み出し輝度信号VSIGおよび読み出しリセット信号VRSTを含む第2の画素信号pixout2と、のうちの少なくともいずれかである。そして、カラム読み出し回路40は、画素信号を増幅する増幅部420と、増幅部420で増幅された画素信号を、探索信号に関連付けてアナログ信号からデジタル信号に変換するAD変換430と、を含み、第1の画素信号pixout1のときの第1の探索信号Vramp1と第2の画素信号pixout2のときの第2の探索信号Vramp2とは、探索レベルが反転した関係に設定可能である。
本第1の実施形態によれば、特に、リセットレベルが先行して出力される低ノイズなローリングシャッタモードと、動体歪みのないグローバルシャッタモードの画素信号の両方を取得可能な画素に対して、サンプルホールド回路を追加することなく小面積で、かつ、低電圧で処理することが可能となる。
具体的には、カラムアンプである第1のオペアンプ421において、第1の帰還キャパシタCf1の接続先を、第1のオペアンプ421の出力端子およびオフセット電位VOSのいずれかに、シングルエンドのローリングシャッタモードとシングルエンドのグローバルシャッタモードに応じて切り替え可能な第1のスイッチ部SW421とバイアス信号線を追加するだけで、動作モードや読み出し信号の信号形態にかかわらず読み出し回路を共用することが可能となる。
本第1の実施形態に係る固体撮像装置10において、画素部20は、複数の第1の画素21の光電変換読み出し部211が行列状に配置された第1の画素アレイ230と、複数の第1の画素21の信号保持部212が行列状に配置された保持部アレイ240と、複数の第2の画素の光電変換読み出し部が行列状に配置された第2の画素アレイ250-1,250-2と、を含んで構成されている。
そして、第1の動作であるローリングシャッタモード時に、第1の画素21および第2の画素22の光電変換読み出し部211,221の読み出し信号が第1の垂直信号線LSGN11にバイパス経路をたどることなく直ちに出力される。また、第2の動作であるグローバルシャッタモード時に、第1の画素の信号保持部212の保持信号が第2の垂直信号線LSGN12に出力される。
第1の基板110には、その中央部を中心として画素部20の各第1の画素21の光電変換読み出し部211が配列された第1の画素アレイ230が形成され、第1の画素アレイ230の第1の垂直信号線LSGN11の配線方向の両側(上側および下側)に第2の画素アレイ250-1,250-2が形成されている。
また、第1の基板110には、第1の垂直信号線LSGN11が形成されている。
第2の基板120には、その中央部を中心として第1の画素アレイ230の各光電変換読み出し部211の出力ノードND21と接続される各第1の画素21の信号保持部212がマトリクス状に配列された保持部アレイ240(領域121)および第2の垂直信号線LSGN12が形成されている。
そして、保持部アレイ240の周囲にカラム読み出し回路40用の領域122,123等が形成されている。
図11は、本発明の第2の実施形態に係る固体撮像装置の画素およびカラム読み出し回路の構成例を示す図である。
本第2の実施形態に係る固体撮像装置10Aでは、ローリングシャッタモード時にカラム読み出し回路40Aへの第1の画素信号が、シングルエンドではなく差動の画素信号として供給される。
そして、電流源Ibias1と基準電位VSSとの接続ライン側に流れる信号が、入力部440を介して増幅部420の第1のオペアンプ421の第2の入力端子(+)側に、第2のサンプリングキャパシタCs2を介して供給される。
また、ローリングシャッタモード期間において、カラム読み出し回路40Aの増幅部420の第1のスイッチ部SW421に対して制御信号CKOSがLレベルで供給される。これにより、第1のスイッチ部SW421は、端子aを端子bとが接続されて、第1の帰還キャパシタCf1は、第1のオペアンプ421の第1の入力端子(-)と出力ノードND421との間に接続される。
また、ローリングシャッタモード期間において、カラム読み出し回路40Aの増幅部420の第2のスイッチ部SW422に対して制御信号VREFSHがクロックで供給される。
図12(C)はグローバルシャッタモード時のシングルエンドの第1の画素信号pixout1を示し、図12(D)はオートゼロスイッチ部SW423の制御信号AZ1および第2のスイッチ部SW422の制御信号VREFSHを示し、図12(E)は第1のスイッチ部SW421の制御信号CKOSを示し、図12(F)はサンプルホールドスイッチ部SW431の制御信号SHを示し、図12(G)はオートゼロスイッチ部SW432の制御信号AZ2を示している。
図12(H)は第1のオペアンプ421の出力信号(アンプ出力)ampoutを示し、図12(I)は第1の探索信号Vramp1を示し、図12(J)は第2のオペアンプ431の入力信号電圧Vcmpを示し、図12(K)は第2のオペアンプ431の出力信号(比較出力)cmpoutを示している。
したがって、その詳細な動作説明はここでは割愛する。
また、画素はグローバルシャッタモードで動作しても良い。具体的には、第2の垂直信号線LSGN12から出力された第2の画素信号pixout2は、カラム読み出し回路40Aの入力部440を介して増幅部420の第1のオペアンプ421の第1の入力端子(-)側に、第1のサンプリングキャパシタCs1を介して供給される。
そして、電流源Ibias1と基準電位VSSとの接続ライン側に流れる信号が、入力部440を介して増幅部420の第1のオペアンプ421の第2の入力端子(+)側に、第2のサンプリングキャパシタCs2を介して供給される。この時も同様に、グローバルシャッタ画素に対して、シェーディングなどのノイズを低減することができる。
図13は、本発明の第3の実施形態に係る固体撮像装置の第1の画素の構成例を示す図である。
スイッチ素子SW22は、端子aが第3の信号線LSGN13に接続された入力ノードND22と接続され、端子bがノードND26に接続されている。
スイッチ素子SW22は、たとえば制御信号GSHSがハイレベルに期間に端子aとbが接続されて導通状態となる。
信号用保持キャパシタCS21は、ノードND26と基準電位VSSに接続されたノードND27との間に接続されている。
スイッチ素子SW23は、端子aが第3の信号線LSGN13に接続された入力ノードND22と接続され、端子bがノードND25に接続されている。
スイッチ素子SW23は、たとえば制御信号GSHRがハイレベルに期間に端子aとbが接続されて導通状態となる。
リセット信号用保持キャパシタCR21は、ノードND25と基準電位VSSに接続されたノードND27との間に接続されている。
スイッチ素子SW24は、端子aがノードND26に接続され、端子bがノードND25に接続されている。
スイッチ素子SW24は、たとえば制御信号CKSTがハイレベルに期間に端子aとbが接続されて導通状態となる。これにより、選択行のリセットレベルと信号レベルの平均化が行われる。
選択トランジスタSEL3S-Trは、制御信号SEL3がHレベルの選択期間に選択されて導通状態となる。これにより、ソースフォロワトランジスタSF3S-Trは信号用保持キャパシタCS21の保持電圧または平均化電圧に応じた列出力の読み出し電圧(VRST,VSIG)を第2の垂直信号線LSGN12-1に出力する。
選択トランジスタSEL3R-Trは、制御信号SEL3がHレベルの選択期間に選択されて導通状態となる。これにより、ソースフォロワトランジスタSF3R-Trはリセット信号用保持キャパシタCR21の保持電圧または平均化電圧に応じた列出力の読み出し電圧(VRST,VSIG)を第2の垂直信号線LSGN12-2に出力する。
次に、差動のグローバルシャッタモード時の読み出し動作について説明する。
図14(A)~(F)は、本第3の実施形態に係る固体撮像装置のグローバルシャッタモード時の主として画素部における読み出し動作を説明するためのタイミングチャートである。
図15(A)~(L)は、本第3の実施形態に係る固体撮像装置のグローバルシャッタモード時の主としてカラム読み出し回路における読み出し動作を説明するためのタイミングチャートである。
図14(C)は第1の画素21の信号保持部212Bのスイッチ素子SW22の制御信号GSHSを示している。図14(D)は第1の画素21の信号保持部212Bのスイッチ素子SW23の制御信号GSHRを示している。図14(E)は第1の画素21の信号保持部212Bのスイッチ素子SW24の制御信号CKSTを示している。図14(F)は第1の画素21の信号保持部212の選択トランジスタSEL3-Trの制御信号SEL3を示している。
図15(D)はグローバルシャッタモード時の差動の第2の画素信号pixout2を示し、図15(E)はオートゼロスイッチ部SW423の制御信号AZ1および第2のスイッチ部SW422の制御信号VREFSHを示し、図15(F)は第1のスイッチ部SW421の制御信号CKOSを示し、図15(G)はサンプルホールドスイッチ部SW431の制御信号SHを示し、図15(H)はオートゼロスイッチ部SW432の制御信号AZ2を示している。
図15(I)は第1のオペアンプ421の出力信号(アンプ出力)ampoutおよび帰還信号ampvstを示し、図15(J)は第1の探索信号Vramp1を示し、図15(K)は第2のオペアンプ431の入力信号電圧Vcmpを示し、図15(L)は第2のオペアンプ431の出力信号(比較出力)cmpoutを示している。
これにより、グローバルシャッタモードの全期間中第1の画素アレイ230と第2の画素アレイ250-1,250-2から第1の垂直信号線LSGN11への電圧信号の出力が抑止(停止)される。
したがって、第2の画素アレイ250-1,250-2は非アクティブ状態に制御される。
また、第1の画素アレイ230は、アクティブ状態であり、出力ノードND21からの電圧信号の信号保持部212Bへの出力可能状態となっている。
そして、制御信号RSTがHレベル期間中に、転送トランジスタTG1-Trが、制御信号TGがHレベルの期間に選択されて導通状態となり、フォトダイオードPD21で光電変換され蓄積された電荷(電子)の蓄積ノードがフローティングディフュージョンFD21と導通状態となり、フォトダイオードPD21およびフローティングディフュージョンFD21が電源電圧VDDの電位にリセットされる。
このとき、リセットトランジスタRST1-Trの制御信号RSTはHレベルに保持されており、フローティングディフュージョンFD21が電源電圧VDDの電位にリセットされたままの状態に保持される。
この状態で時刻t22に、各光電変換読み出し部211では、ソースフォロワトランジスタSF1-Trにより、フローティングディフュージョンFD21の電荷が電荷量に応じた電圧信号に変換され、列出力の読み出しリセット信号VRSTとして出力ノードND21から出力される。
そして、リセット期間の終了のため、時刻t22を経過後、リセットトランジスタRST1-Trの制御信号RSTはLレベルに切り替えられ、リセットトランジスタRST1-Trは非導通状態となる。
次に、時刻t23を含む所定期間に、第1の画素21の信号保持部212Bのスイッチ素子SW22の制御信号GSHSおよびスイッチ素子SW23の制御信号GSHRがHレベルに切り替えられて、信号用保持キャパシタCS21およびリセット信号用保持キャパシタCR21が初期化される。また、定電流源Ibias3がオン状態となるように制御される。
かつ、時刻t23を含む所定期間において、各光電変換読み出し部211の出力ノードND21から出力される読み出しリセット信号VRSTは、第3の信号線LSGN13を通して対応する信号保持部212Bに伝送され、スイッチ素子SW23を通してリセット信号用保持キャパシタCR21に保持される。
そして、第1の画素21Bの信号保持部212Bのスイッチ素子SW22の制御信号GSHSおよびスイッチ素子SW23の制御信号GSHRがLレベルに切り替えられ、スイッチ素子SW22およびSW23が非導通状態となる。
転送期間には、各光電変換読み出し部211において、転送トランジスタTG1-Trが、制御信号TGがHレベルの期間に選択されて導通状態となり、フォトダイオードPD21で光電変換され蓄積された電荷(電子)がフローティングディフュージョンFD21に転送される。
転送期間が終了すると、転送トランジスタTG1-Trの制御信号TGがLレベルに切り替えられ、転送トランジスタTG1-Trが非導通状態となる。
信号保持部212Bにおいて、時刻t25を含む所定期間に制御信号GSHSがHレベルに切り替えられてスイッチ素子SW22が導通状態となり、定電流源Ibias3がオン状態となるように制御される。
そして、時刻t26において、信号用保持キャパシタCS21に保持された読み出し輝度信号VSIGの読み出し、並びに、リセット信号用保持キャパシタCR21に保持された読み出しリセット信号VRSTの読み出しが並行して行われる。
同様に、各信号保持部212Bにおいては、ゲートがノードND25に接続されたソースフォロワトランジスタSF3R-Trにより、ノードND25に接続されたリセット信号用保持キャパシタCR21の保持電圧に応じて、列出力の読み出しリセット信号VRSTとして第2の垂直信号線LSGN12-2に出力され、カラム読み出し回路40に供給される。
これにより、選択行のリセットレベルと信号レベルの平均化が行われる。
そして、時刻t28において、信号用保持キャパシタCS21に保持された読み出し輝度信号VSIG、並びに、リセット信号用保持キャパシタCR21に保持された読み出しリセット信号VRSTを平均化して信号の読み出しが並行して行われる。
同様に、各信号保持部212Bにおいては、ゲートがノードND25に接続されたソースフォロワトランジスタSF3R-Trにより、ノードND25における平均化電圧に応じて、列出力の平均化信号AVSRとして第2の垂直信号線LSGN12-2に出力され、カラム読み出し回路40に供給される。
VOUTR(t26)-VOUTS(t26)=VR+VOS2-(VS+VOS1)
VOUTR(t28)-VOUTS(t28)=
(VR+VS)/2+VOS2-((VR+VS)/2+VOS1)
VOUTR(t26)-VOUTS(t26)―{VOUTR(t28)-VOUTS(t28)}
=VR-VS
また、差動のグローバルシャッタモード期間において、カラム読み出し回路40の増幅部420の第1のスイッチ部SW421に対して制御信号CKOSがLレベルで供給される。これにより、第1のスイッチ部SW421は、端子aを端子bとが接続されて、第1の帰還キャパシタCf1は、第1のオペアンプ421の第1の入力端子(-)と出力ノードND421との間に接続される。
また、差動のグローバルシャッタモード期間において、カラム読み出し回路40の増幅部420の第2のスイッチ部SW422に対して制御信号VREFSHがクロックで供給される。
これと並行して、グローバルシャッタモード時の差動の他方の第2の画素信号pixout2d2が、入力部440の第2の出力端子TO2から、第2のサンプリングキャパシタCs2が接続された第1のオペアンプ421の第2の入力端子(+)側に供給される。
これにより、増幅部420の第1のオペアンプ421がリセット状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、所定のDC電位、たとえば参照電位Vrefとなる。
制御信号SHおよびAZ2がHレベルに設定される期間としては、制御信号SH、AZ2の順で長く設定される。
これにより、AD変換部430の第2のオペアンプ431がリセット状態となる。
そして、図15(K)に示すように、第4のサンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp1を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2とが比較され、参照電位Vref2と交差するまでの間、図15(L)に示すように、比較出力信号cmpoutがHレベルで出力される。この交差するまでの時間を図示しないカウンタで測定することにより、AD変換が行われる。
そして、第1のオペアンプ4211の出力信号ampoutは、参照電位Vrefを基準に、読み出しリセット信号電圧VRSTと低電位の読み出し輝度信号VSIGの差分に容量比倍Gを掛け合わせたレベル増幅された信号(Vref+G*(VRST-VSIG))となる。また、帰還信号ampvstは(Vref+G´*(VRST-VSIG))となる。
そして、転送期間後の所定期間、図15(G)に示すように、制御信号SHがHレベルに設定され、AD変換部430のサンプルホールドスイッチ部SW431が導通状態となる。
その結果、増幅部420の第1のオペアンプ421の出力信号(アンプ出力)ampoutは、信号(Vref+G*(VRST-VSIG))となり、サンプルホールドスイッチ部SW431を通してAD変換部430に転送され、第4のサンプリングキャパシタCs4に保持される。
そして、図15(K)に示すように、第4のサンプリングキャパシタCs4に保持された電圧と探索信号入力部432による探索信号Vramp1を合成した信号電圧Vcmpが第2のオペアンプ431の第1の入力端子(-)側に供給される。
第2のオペアンプ431においては、第1の入力端子(-)に第3のサンプリングキャパシタCs3を介して入力される入力信号電圧Vcmpと第2の入力端子(+)に供給される参照電位Vref2とが比較され、参照電位Vref2と交差するまでの間、図15(L)に示すように、比較出力信号cmpoutがHレベルで出力される。この交差するまでの時間を図示しないカウンタで測定することにより、AD変換が行われる。
図15(A)~(L)においては、時刻t31に第1の画素21の信号保持部212Bにより読み出し輝度信号VSIGおよび読み出しリセット信号VRSTが同時並列的に読み出されてカラム読み出し回路40の第1のオペアンプ421に入力される場合を例としている。
同様に、図15(A)~(L)において、時刻t32に第1の画素21の信号保持部212Bにより読み出し輝度信号VSIGおよび読み出しリセット信号VRSTの平均化信号AVSRが同時並列的に読み出されてカラム読み出し回路40に入力される場合を例としている。
Vinp(t31)=Vref+(Qinj/(Cs+Cf))=V´ref
Cs×(V´ref-Vrst)+Cf×0+Qinj
=Cs×(V´ref-Vrst)+Cf×(V´ref-Vout)
Vout(t31)=V´ref-Qinj/Cf
Cs×(V´ref-Vrst)+Cf×V´ref
=Cs×(Vinp-(Vrst+Vsig)/2)+Cf×Vinp
Vinp(t32)
=V´ref+(Cs/(Cs+Cf))×(Vrst-VsiG)/2
Cs×(V´ref-Vrst)+Cf×0+Qinj
=Cs×(Vinp-(Vrst+Vsig)/2)+Cf×(Vinp-Vout)
Vout(t32)
=V´ref-(Qinj/Cf)+(Cs/Cf)×(Vrst-Vsig)
Vout(t32)-Vout(t31)
=(Cs/Cf)×(Vrst-Vsig)
図17は、差動のグローバルシャッタモード時の第1のオペアンプの入力レンジの制御の一例を説明するためのである。
そして、PMOSトランジスタPT41のソースとPMOSトランジスタPT43のソース同士が接続されて、その接続ノードが電源電位VDDに接続されている。
NMOSトランジスタPT41のソースとNMOSトランジスタPT43のソース同士が接続されて、その接続ノードが基準電位VSSに接続されて電流源I41に接続されている。
そして、ノードND41がPMOSトランジスタPT41,PT43のゲートに接続され、ノードND42が出力ノードND421に接続されている。
また、PMOSトランジスタPT42,PT44のゲートがバイアス電位Vbpの供給端子Tvbpに共通に接続されている。
スイッチ部SW41は、たとえば制御信号CTLがLレベルのときは端子aと端子bとを導通状態に保持し、制御信号CTLがHレベルのときは端子aと端子cとを導通状態に保持する。
第1のオペアンプ421は、ゲイン設定Gが高いときはスイッチ部SW41により、NMOSトランジスタNT42,NT44のゲートがテレスコピック電位Vtrに接続されるように制御され、いわゆるテレスコピックアンプとして機能するように制御される。これは、ゲインエラーを低減するためである。
一方、ゲインが×4、×8の高いゲインの場合は、入力レンジが小さいため、NMOSトランジスタNT42,NT44のゲートをテレスコピック電位Vtrに接続し、高いゲインのテレスコピックアンプとして機能させ、明時のゲインエラーを低減する。
図18は、本発明の第4の実施形態に係るカラム読み出し回路の構成例を示す回路図である。
図19(A)および(B)は、本第4の実施形態に係るAD変換部に採用される反転二分探索法に対応した探索信号入力部の構成例を説明するための図である。
そして、第1~第3の実施形態においては、探索信号Vrampとして、第2のモード信号MOD2(シングルエンドのグローバルシャッタモード)のとき第2の探索信号Vramp2が探索信号入力部432に供給される。
すなわち、第1~第3の実施形態においては、AD変換部430にレベル反転させた第1の探索信号Vramp1と第2の探索信号Vramp2を採用している。
第4のサンプリングキャパシタCs4-1~Cs4-xは、一方の電極(端子)がAD変換部430Cの入力ノードND431に共通に接続され、他方の電極(端子)が、対応して配置されたスイッチ部SW432-1~SW432-xの端子aに接続されている。
スイッチ部SW432-1~SW432-xの端子bが参照電位Vrefに接続され、端子cがグランドGNDに接続されている。
このように、スイッチ部SW432-1~SW432-xを制御信号CTR SARにより参照電位VrefとグランドGNDで、この順に交互にスイッチすることにより、図19(A)に示すように、読み出しリセット信号VRST、読み出し輝度信号VSIGの順に読み出される第1の画素信号pixout1をAD変換することができる。
このように、スイッチ部SW432-1~SW432-xを制御信号CTR SARによりグランドGNDと参照電位Vref、この順に交互にスイッチすることにより、図19(B)に示すように、読み出し輝度信号VSIG、読み出しリセット信号VRSTの順に読み出される第2の画素信号pixout2をAD変換することができる。
さらに、電子機器300は、このCMOSイメージセンサ310の画素領域に入射光を導く(被写体像を結像する)光学系(レンズ等)320を有する。
電子機器320は、CMOSイメージセンサ310の出力信号を処理する信号処理回路(PRC)330を有する。
信号処理回路330で処理された画像信号は、液晶ディスプレイ等からなるモニタに動画として映し出し、あるいはプリンタに出力することも可能であり、またメモリカード等の記録媒体に直接記録する等、種々の態様が可能である。
そして、カメラの設置の要件に実装サイズ、接続可能ケーブル本数、ケーブル長さ、設置高さなどの制約がある用途に使われる、たとえば、監視用カメラ、医療用内視鏡用カメラなどの電子機器を実現することができる。
Claims (18)
- 光電変換を行う画素が配置された画素部と、
前記画素から信号線に読み出される画素信号をアナログ信号からデジタル信号に変換するアナログデジタル(AD)変換機能を有する読み出し回路と、を有し、
前記画素から読み出される前記画素信号は、
第1の動作により前記画素から順に読み出される読み出しリセット信号および読み出し輝度信号を含む第1の画素信号と、
第2の動作により前記画素から順に読み出される読み出し輝度信号および読み出しリセット信号を含む第2の画素信号と、のうちの少なくともいずれかであり、
前記読み出し回路は、
前記画素信号を増幅する増幅部と、
前記増幅部で増幅された画素信号を、探索信号に関連付けてアナログ信号からデジタル信号に変換するAD変換部と、を含み、
前記第1の画素信号のときの第1の探索信号と前記第2の画素信号のときの第2の探索信号とは、探索レベルが反転した関係に設定可能である
固体撮像装置。 - 前記増幅部は、
第1の演算増幅器と、
前記第1の画素信号または前記第2の画素信号の入力ラインと前記第1の演算増幅器の第1の入力端子との間に接続された第1のサンプリングキャパシタと、
前記第1の演算増幅器の出力端子と前記第1の入力端子との間に接続される第1の帰還キャパシタと、
オフセット電位と、
前記帰還キャパシタの一端側を前記第1の演算増幅器の出力端子または前記オフセット電位に選択的に接続する第1のスイッチ部と、を含み、
前記第1の演算増幅器の第2の入力端子は少なくとも参照電位に接続可能である
請求項1記載の固体撮像装置。 - 前記増幅部は、
前記第1の画素信号または前記第2の画素信号の入力ラインと前記第1の演算増幅器の第2の入力端子との間に接続された第2のサンプリングキャパシタと、
前記第1の演算増幅器の前記第2の入力端子と基準電位との間に接続された第2の帰還キャパシタと、
前記参照電位を前記第1の演算増幅器の前記第2の入力端子に選択的に接続する第2のスイッチ部と、を含む
請求項2記載の固体撮像装置。 - 前記AD変換部は、
第2の演算増幅器と、
前記増幅部の信号出力ラインに接続されたサンプルホールドスイッチと、
前記第2の演算増幅器の第1の入力端子と前記サンプルホールドスイッチとの間に接続された入力キャパシタと、
前記入力キャパシタの前記サンプルホールドスイッチとの接続端子側と前記探索信号の供給ラインとの間に接続され、前記探索信号を前記入力キャパシタの前記サンプルホールドスイッチとの接続端子側に入力する探索信号入力部と、を含み、
前記第2の演算増幅器の第2の入力端子は参照電位に接続されている
請求項2記載の固体撮像装置。 - 前記AD変換部の前記探索信号入力部は、
一端子側が前記入力キャパシタの前記サンプルホールドスイッチとの接続端子側に接続され、他端子側が前記探索信号の供給ライン側に接続された探索信号入力用キャパシタを含む
請求項4記載の固体撮像装置。 - 前記AD変換部の前記探索信号入力部は、
一端子側が前記入力キャパシタの前記サンプルホールドスイッチとの接続端子側に接続された複数のキャパシタと、
前記複数のキャパシタに対応して配置され、二分探索法に従った制御信号に応じて当該対応するキャパシタの他端側を、参照電位または基準電位に選択的に接続する複数のスイッチと、を含む
請求項4記載の固体撮像装置。 - 前記増幅部は、
前記第1の演算増幅器の前記第1の入力端子と出力端子との間に接続された第1のオートゼロスイッチを含み、
前記AD変換部は、
前記第2の演算増幅器の前記第1の入力端子と出力端子との間に接続された第2のオートゼロスイッチを含む
請求項4記載の固体撮像装置。 - 前記第1の画素信号がシングルエンドの信号として前記増幅部の第1のサンプリングキャパシタに入力される場合、
前記増幅部の第1の帰還キャパシタは前記第1のスイッチ部により前記第1の演算増幅器の出力端子に接続され、前記第1の演算増幅器の第2の入力端子が前記参照電位に接続され、
前記AD変換部には前記第1の探索信号が供給され、
前記第2の画素信号がシングルエンドの信号として前記増幅部の第1のサンプリングキャパシタに入力される場合、
前記増幅部の第1の帰還キャパシタは前記第1のスイッチ部により前記オフセット電位に選択的に接続され、前記第1の演算増幅器の第2の入力端子が前記参照電位に接続され、
前記AD変換部には前記第1の探索信号とは探索レベルが反転した関係にある前記第2の探索信号が供給される
請求項2記載の固体撮像装置。 - 前記第1の画素信号が差動の信号として前記増幅部の第1のサンプリングキャパシタおよび第2のサンプリングキャパシタに入力される場合、
前記増幅部の第1の帰還キャパシタは前記第1のスイッチ部により前記第1の演算増幅器の出力端子に接続され、
前記AD変換部には前記第1の探索信号が供給される
請求項2記載の固体撮像装置。 - 前記第2の画素信号が差動の信号として前記増幅部の第1のサンプリングキャパシタおよび第2のサンプリングキャパシタに入力される場合、
前記増幅部の第1の帰還キャパシタは前記第1のスイッチ部により前記第1の演算増幅器の出力端子に接続され、
前記AD変換部には前記第1の探索信号が供給される
請求項2記載の固体撮像装置。 - 光電変換読み出し部および信号保持部を含む第1の画素と前記光電変換読み出し部を含む第2の画素のうち、少なくとも前記第1画素が配置された前記画素部と、
前記画素部から画素信号の読み出しを行う読み出し部と、
前記光電変換読み出し部の読み出し信号が出力される第1の信号線と、
前記信号保持部の保持信号が出力される第2の信号線と、を有し、
少なくとも前記第1の画素の前記光電変換読み出し部は、
出力ノードと、
蓄積期間に光電変換により生成した電荷を蓄積する光電変換素子と、
前記光電変換素子に蓄積された電荷を転送期間に転送可能な転送素子と、
前記転送素子を通じて前記光電変換素子で蓄積された電荷が転送されるフローティングディフュージョンと、
前記フローティングディフュージョンの電荷を電荷量に応じた電圧信号に変換し、変換した信号を前記出力ノードに出力するソースフォロワ素子と、
リセット期間に前記フローティングディフュージョンを所定の電位にリセットするリセット素子と、
第1の期間に前記出力ノードを前記第1の信号線と電気的に接続する選択素子と、を含み、
前記信号保持部は、
前記第1の画素の前記光電変換読み出し部の出力ノードから出力される信号を保持可能な信号保持キャパシタと、
第2の期間に前記信号保持キャパシタを前記光電変換読み出し部の出力ノードと選択的に接続するスイッチ素子と、
前記第2の期間に前記信号保持キャパシタに保持された信号を保持電圧に応じて出力するソースフォロワ素子を含み、変換した信号を選択的に前記第2の信号線に出力する出力部と、を含む
請求項1記載の固体撮像装置。 - 前記画素部は、少なくとも、
複数の前記第1の画素の前記光電変換読み出し部が行列状に配置された第1の画素アレイと、
前記複数の前記第1の画素の前記信号保持部が行列状に配置された保持部アレイと、を含む
請求項11記載の固体撮像装置。 - 前記画素部は、
複数の前記第2の画素の前記光電変換読み出し部が行列状に配置された第2の画素アレイを有し、
前記第2の画素の前記光電変換読み出し部は、
蓄積期間に光電変換により生成した電荷を蓄積する光電変換素子と、
前記光電変換素子に蓄積された電荷を転送期間に転送可能な転送素子と、
前記転送素子を通じて前記光電変換素子で蓄積された電荷が転送されるフローティングディフュージョンと、
前記フローティングディフュージョンの電荷を電荷量に応じた電圧信号に変換するソースフォロワ素子と、
リセット期間に前記フローティングディフュージョンを所定の電位にリセットするリセット素子と、
第1の期間に前記ソースフォロワ素子による電圧信号の出力ラインを前記第1の信号線と電気的に接続する選択素子と、を含む
請求項12記載の固体撮像装置。 - 前記読み出し部は、
第1の動作時には、前記第1の画素の前記第1の画素アレイおよび前記第2の画素の前記第2の画素アレイをアクティブにして画素信号の読み出しを行う
請求項11記載の固体撮像装置。 - 前記読み出し部は、
第2の動作時には、前記第1の画素および前記第2の画素の前記光電変換読み出し部における前記選択素子を非選択状態とした状態で、前記第1の画素の前記第1の画素アレイおよび前記保持部アレイをアクティブにして画素信号の読み出しを行う
請求項11記載の固体撮像装置。 - 第1の基板と、
第2の基板と、を含み、
前記第1の基板と前記第2の基板は接続部を通して接続された積層構造を有し、
前記第1の基板には、
少なくとも、前記第1の画素の前記光電変換読み出し部、および前記第1の信号線が形成され、
前記第2の基板には、
少なくとも、前記第1の画素の前記信号保持部、前記第2の信号線、および前記読み出し部の少なくとも一部が形成されている
請求項11記載の固体撮像装置。 - 光電変換を行う画素が配置された画素部と、
前記画素から信号線に読み出される画素信号をアナログ信号からデジタル信号に変換するアナログデジタル(AD)変換機能を有する読み出し回路と、を有し、
前記読み出し回路は、
前記画素信号を増幅する増幅部と、
前記増幅部で増幅された画素信号を、探索信号に関連付けてアナログ信号からデジタル信号に変換するAD変換部と、を含む、
固体撮像装置の駆動方法であって、
前記画素から読み出される前記画素信号は、
第1の動作により前記画素から順に読み出される読み出しリセット信号および読み出し輝度信号を含む第1の画素信号と、
第2の動作により前記画素から順に読み出される読み出し輝度信号および読み出しリセット信号を含む第2の画素信号と、のうちの少なくともいずれかであり、
前記読み出し回路に供給する前記探索信号について、
前記第1の画素信号のときの第1の探索信号と前記第2の画素信号のときの第2の探索信号とで、探索レベルが反転した関係に設定する
固体撮像装置の駆動方法。 - 固体撮像装置と、
前記固体撮像装置に被写体像を結像する光学系と、を有し、
前記固体撮像装置は、
光電変換を行う画素が配置された画素部と、
前記画素から信号線に読み出される画素信号をアナログ信号からデジタル信号に変換するアナログデジタル(AD)変換機能を有する読み出し回路と、を含み、
前記画素から読み出される前記画素信号は、
第1の動作により前記画素から順に読み出される読み出しリセット信号および読み出し輝度信号を含む第1の画素信号と、
第2の動作により前記画素から順に読み出される読み出し輝度信号および読み出しリセット信号を含む第2の画素信号と、のうちの少なくともいずれかであり、
前記読み出し回路は、
前記画素信号を増幅する増幅部と、
前記増幅部で増幅された画素信号を、探索信号に関連付けてアナログ信号からデジタル信号に変換するAD変換部と、を含み、
前記第1の画素信号のときの第1の探索信号と前記第2の画素信号のときの第2の探索信号とは、探索レベルが反転した関係に設定可能である
電子機器。
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TWM610099U (zh) * | 2020-03-20 | 2021-04-01 | 神盾股份有限公司 | 影像感測裝置 |
CN111405195B (zh) * | 2020-03-23 | 2021-06-22 | 西安微电子技术研究所 | 一种双曝光cmos图像传感器的数据转换装置及其转换方法 |
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012019410A (ja) * | 2010-07-08 | 2012-01-26 | Toshiba Corp | 固体撮像装置 |
JP2013055447A (ja) * | 2011-09-02 | 2013-03-21 | Renesas Electronics Corp | 固体撮像装置 |
JP2015091081A (ja) * | 2013-11-07 | 2015-05-11 | ルネサスエレクトロニクス株式会社 | 固体撮像素子 |
Family Cites Families (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006197393A (ja) * | 2005-01-14 | 2006-07-27 | Canon Inc | 固体撮像装置、カメラ、及び固体撮像装置の駆動方法 |
JP4823743B2 (ja) * | 2006-04-03 | 2011-11-24 | 三星電子株式会社 | 撮像装置,及び撮像方法 |
JP2008011284A (ja) * | 2006-06-30 | 2008-01-17 | Fujitsu Ltd | 画像処理回路、撮像回路および電子機器 |
JP2008252195A (ja) * | 2007-03-29 | 2008-10-16 | Yamaha Corp | Cmos固体撮像装置 |
JP5077091B2 (ja) * | 2008-06-23 | 2012-11-21 | コニカミノルタビジネステクノロジーズ株式会社 | 固体撮像装置 |
JP2010251957A (ja) * | 2009-04-14 | 2010-11-04 | Sony Corp | Ad変換装置、固体撮像素子、およびカメラシステム |
US20100309340A1 (en) * | 2009-06-03 | 2010-12-09 | Border John N | Image sensor having global and rolling shutter processes for respective sets of pixels of a pixel array |
JP5531797B2 (ja) * | 2010-06-15 | 2014-06-25 | ソニー株式会社 | 固体撮像素子およびカメラシステム |
US8953075B2 (en) * | 2012-03-30 | 2015-02-10 | Pixim, Inc. | CMOS image sensors implementing full frame digital correlated double sampling with global shutter |
JP2014053777A (ja) * | 2012-09-07 | 2014-03-20 | Canon Inc | 撮像装置 |
US8773562B1 (en) * | 2013-01-31 | 2014-07-08 | Apple Inc. | Vertically stacked image sensor |
JP5886806B2 (ja) * | 2013-09-17 | 2016-03-16 | キヤノン株式会社 | 固体撮像装置 |
CN103607547B (zh) * | 2013-12-09 | 2017-02-15 | 江苏思特威电子科技有限公司 | 镜像像素成像装置及其成像方法 |
CN203801011U (zh) * | 2013-12-09 | 2014-08-27 | 江苏思特威电子科技有限公司 | 成像装置 |
JP6075646B2 (ja) * | 2014-03-17 | 2017-02-08 | ソニー株式会社 | 固体撮像装置およびその駆動方法、並びに電子機器 |
CN104333719B (zh) * | 2014-11-12 | 2018-04-06 | 上海集成电路研发中心有限公司 | 全局快门像素单元及其信号采集方法和制造方法 |
CA3025801A1 (en) * | 2015-06-02 | 2016-12-08 | Uti Limited Partnership | Image sensor circuits and methods |
CN105791715B (zh) * | 2016-03-10 | 2018-09-18 | 长春长光辰芯光电技术有限公司 | 高动态范围图像传感器像素的全局快门控制方法 |
CN106375688B (zh) * | 2016-09-06 | 2019-11-22 | 上海集成电路研发中心有限公司 | 一种cmos图像传感器及其信号传输方法 |
US10778919B2 (en) * | 2017-01-18 | 2020-09-15 | Samsung Electronics Co., Ltd. | Image sensor |
-
2018
- 2018-03-28 US US16/499,843 patent/US10791293B2/en active Active
- 2018-03-28 WO PCT/JP2018/012723 patent/WO2018181463A1/ja active Application Filing
- 2018-03-28 JP JP2019509966A patent/JP6951423B2/ja active Active
- 2018-03-28 CN CN201880021874.1A patent/CN110771157B/zh active Active
- 2018-03-28 EP EP18777854.3A patent/EP3606048B1/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012019410A (ja) * | 2010-07-08 | 2012-01-26 | Toshiba Corp | 固体撮像装置 |
JP2013055447A (ja) * | 2011-09-02 | 2013-03-21 | Renesas Electronics Corp | 固体撮像装置 |
JP2015091081A (ja) * | 2013-11-07 | 2015-05-11 | ルネサスエレクトロニクス株式会社 | 固体撮像素子 |
Non-Patent Citations (3)
Title |
---|
J. AOKI ET AL.: "A Rolling-Shutter Distortion-Free 3D Stacked Image Sensor with -160dB Parasitic Light Sensitivity In-Pixel Storage Node", ISSCC 2013 / SESSION 27 / IMAGE SENSORS, vol. 27.3, 2013 |
S. OKURA ET AL.: "A 3.7 M-Pixel 1300-fps CMOS Image Sensor With 5.0 G-Pixel/s High-Speed Readout Circuit", IEEE JOURNAL OF SOLID-STATE CIRCUITS, vol. 50, no. 4, April 2015 (2015-04-01), pages 1016 - 1024, XP011576665, doi:10.1109/JSSC.2014.2387201 |
See also references of EP3606048A4 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110611782A (zh) * | 2019-10-28 | 2019-12-24 | 思特威(上海)电子科技有限公司 | 全局曝光图像传感器 |
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