JP3548244B2 - Photoelectric conversion device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a photoelectric conversion device formed on a semiconductor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there are several types of photoelectric conversion devices in which a photoelectric conversion pixel has its output line, and is classified into a MOS type, a SIT type, a FET type, a CMD type, a bipolar type, and the like according to the pixel configuration. .
[0003]
FIG. 6 shows a bipolar type two-dimensional photoelectric conversion device in which a pixel is formed by a bipolar transistor and a carrier generated by light is accumulated in a base region thereof.
[0004]
In FIG. 6, reference numeral 1 denotes a photoelectric conversion pixel, which includes an npn-type bipolar transistor 2, a P-type MOS transistor 3 connected to its base for resetting the base, and a pixel capacitor 4 for controlling the base potential. 5 is a storage signal output line of a pixel connected to the emitter of the bipolar transistor 2, 6 is a MOS transistor for resetting the output line 5, 7 is a transfer capacitor for holding and transferring the output voltage of the photoelectric conversion pixel 1, and 8 is a transfer capacitor. A MOS transistor for switching the output line 5 and the storage capacitor 7, a horizontal output line 9 to which a signal from the transfer storage capacitor 7 is transferred, and a MOS transistor 10 for switching the storage capacitor 7 and the horizontal according to the output of the horizontal shift register 33. A MOS transistor for switching the output line 9, a preamplifier 11 for amplifying a signal appearing on the horizontal output line 9, and an output terminal 12 of the preamplifier 11.
[0005]
Reference numeral 13 denotes a MOS transistor for resetting the horizontal output line 9, reference numeral 14 denotes a drive line for driving pixels, reference numeral 15 denotes a drive pulse input line, and reference numeral 16 denotes a vertical row selected according to the output of the vertical shift register 34. MOS transistor for switching between the driving line 14 and the driving pulse input line 15 of the photoelectric conversion device._VCIs an input terminal for applying a pulse φVC to the gate of the MOS transistor 6, 19 is an input terminal for applying a pulse φT to the gate of the MOS transistor 8, and 20 is a pulse φHC to the gate of the MOS transistor 13. Is an input terminal for applying the driving pulse φR.
[0006]
FIG. 6 shows an area sensor of 2 × 2 photoelectric conversion pixels for the sake of simplicity. The outputs of the vertical shift register are V1 and V2, and the outputs of the horizontal shift register are H1 and H2. In reality, there are many examples in which pixels of 256 × 256 or more are arranged.
[0007]
FIG. 7 is a pulse timing chart for explaining the operation of the two-dimensional photoelectric conversion device shown in FIG. The pulses in FIG. 7 are generally shown at a high level and a low level._VCExists.
[0008]
First, V1 from the vertical shift register 34 becomes High, and the drive pulse φR of the input terminal 21 changes to the reference potential V._VCBecomes High, the first row of the two-dimensional photoelectric conversion pixels is driven. In the photoelectric conversion pixel 1, the P-type MOS transistor (hereinafter, referred to as PMOS) 3 is turned off, the base potential of the bipolar transistor 2 rises through the pixel capacitor 4, the emitter current flows, and the signal voltage accumulated at the base of the pixel is reduced. , The pulse φVC is Low, so that it appears on the output line 5 in a floating state. Since the outputs H1 and H2 of the horizontal shift register 33 are both Low and the pulse φT is High, the output signal of the floating signal output line 5 is stored in the storage capacitor 7 and then the outputs H1 and H2 of the horizontal shift register 33 are sequentially High. Thus, the carrier of the storage capacitor 7 is output from the output terminal 12 through the output line 9 and the preamplifier 11. When the output H1 becomes High and the column of the output H1 is driven and the carrier of the storage capacitor 7 is discharged, the output H1 becomes Low, the pulse φHC becomes High, and the signal line 9 is reset. Then, the column of the output H2 is driven and the carrier signal is sequentially read out from the signal line 9.
[0009]
In the pixels in each row, the vertical shift register V1 remains High and the driving pulse φR goes to Low level to turn on the PMOS 3, and the base potential of the bipolar transistor 2 in the first row is set to the reference potential V._VCIt becomes. Next, the signal output line 5 changes the pulse φVC to High, and when the MOS transistor 6 is turned on, the reference potential V_VCWhen the driving pulse φR becomes High in a state where the voltage is fixed to, the PMOS 3 is turned off and the bipolar transistor 2 in the first row is turned on, and the emitter current and the base current flow. Going down, the base potential becomes V_VCIt becomes about +0.6 V, and the pixel capacitance 4 is reset. When this occurs, the drive pulse φR changes to the intermediate level V_VC, The base potential drops through the pixel capacitor 4 and the emitter potential V_VCReverse bias. Then, the output V1 becomes Low, and the driving of this row ends. From here, the pixels in the first row enter an accumulation operation for accumulating the optical carriers in the base region until the first row is selected again.
[0010]
Next, the output V2 becomes High, the second row is selected and driven, the carrier signal is output, and the operation when resetting the pixels is the same as that of the first row.
[0011]
In the above-described bipolar photoelectric conversion device, the signal voltage accumulated in the pixel capacitance substantially defined by the pixel capacitance 4 appears in the storage capacitance 7 almost as it is. If the storage capacitor 7 is made sufficiently large with respect to the pixel capacitor 4, the signal charge amount will be amplified by the ratio of the above-described capacitance, and the signal output path, the output line 5, the storage capacitor 7, the output line 9, the preamplifier 11 can reduce the influence of noise.
[0012]
[Problems to be solved by the invention]
However, in the above-described conventional example, when a signal is transferred from the storage capacitor 7 to the horizontal output line 9 in FIG. 6, the signal is capacitance-divided due to the floating capacitance of the horizontal output line 9, and the signal potential decreases. Further, even in the dark, the output in the dark varies due to the variation in the characteristics of each pixel, and the S / N ratio is reduced. In particular, in a conventional example as shown in FIG. 6 in which a bipolar transistor is used for a light receiving pixel, the storage capacitor 7 is often large, and when an emitter current for charging the storage capacitor 7 flows when reading a signal from the pixel, the pixel is The signal charge on the base is destroyed. The greater the amount of destruction, the greater the noise and the lower the S / N ratio becomes.
[0013]
Furthermore, a general conventional photoelectric conversion pixel has only a simple photoelectric conversion function of reset → accumulation → readout, and signal processing of pixel output must be performed in an area other than the photoelectric conversion pixel. It had restrictions such as requiring a field memory.
[0014]
An object of the present invention is to obtain a signal from which noise components included in photoelectric conversion pixels have been removed without using a field memory as in the conventional example.
[0015]
Means and Action for Solving the Problems
To achieve the above objectives,The photoelectric conversion device according to the present invention includes a photoelectric conversion pixel including an amplification unit that inputs, amplifies, and outputs the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
An output line connected to an output section of the amplification means,
An amplifier in which the output line and the input unit are capacitively coupled;
A switch connected between an input portion of the amplifier and a predetermined potential, and selectively switching a potential of the input portion of the amplifier to the predetermined potential and a floating potential;
Including connection control means for controlling the connection between the output unit of the amplifier and the output line,
The first signal is supplied to the amplifying unit in a state where the potential of the input unit of the amplifier is set to the predetermined potential by the switch, and the output unit and the output line of the amplifier are disconnected by the connection control unit. And then read out to the output line,
After that, the switch controls the potential of the input section of the amplifier to a floating potential and sets the potential of the input section of the amplifier to the floating potential, and connects the output section of the amplifier to the output line by the connection control means. Read the output signal of the amplifier to the output line, and set the output line to a potential based on the first signal;
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the output line is supplied to an input of the amplifying unit, and an input of the amplifying unit is set to a potential based on the first signal. Set to
After the reset, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the output line.In this configuration, the output signal of the amplifier is fed back to the input of the amplifying unit, and the noise component included in the photoelectric conversion pixel is removed.
[0016]
Further, the photoelectric conversion device of the present invention is a photoelectric conversion pixel including amplification means for inputting, amplifying and outputting the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
An output line connected to an output section of the amplification means,
Amplifier means having a negative gain connected to the output line;
Including connection control means for controlling the connection between the output unit and the output line of the amplifier means,
In a state in which the output unit of the amplifier unit and the output line are not connected, the first signal is amplified by the amplifier unit and then read to the output line,
Thereafter, an output signal of the amplifier is read out to the output line by connecting an output section of the amplifier and the output line, and the output line is set to a potential based on the first signal,
After that, the photoelectric conversion pixel is reset, and the output signal of the amplifier read out to the output line is supplied to the input of the amplifier, and the input of the amplifier is based on the first signal. Set to potential,
After the reset, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the output line.
Further, the photoelectric conversion device of the present invention includes a plurality of photoelectric conversion pixels arranged in one line or two-dimensional shape, including an amplifying means for inputting, amplifying, and outputting the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
One array of the plurality of photoelectric conversion pixels connected one by one to each of the output units of the plurality of amplifying units of the plurality of photoelectric conversion pixels arranged in one line, or the two-dimensionally arranged photoelectric conversion pixels A plurality of first output lines commonly connected one by one to output units of a plurality of amplifying means of a plurality of photoelectric conversion pixels of each line in each direction;
A plurality of amplifiers each having an input unit capacitively coupled to each of the plurality of first output lines,
A switch connected between an input portion of the amplifier and a predetermined potential, and selectively switching a potential of the input portion of the amplifier to the predetermined potential and a floating potential;
Connection control means for controlling connection between an output section of the amplifier and the first output line capacitively coupled to the input section;
A second output line for commonly outputting signals from the plurality of amplifiers;
A plurality of transfer switch means for transferring signals from the plurality of amplifiers to the second output line;
A horizontal scanning circuit that controls the plurality of transfer switch units so that signals from the plurality of amplifiers are transferred to the second output line in a time-series manner,
The first signal is output in a state where the potential of the input section of the amplifier is set to the predetermined potential by the switch, and the output section of the amplifier is not connected to the first output line by the connection control means. Amplifying by the amplifying means and then reading out to the first output line,
Thereafter, the switch controls the potential of the input section of the amplifier to a floating potential, and sets the potential of the input section of the amplifier to a floating potential, and the output section of the amplifier and the first output line are connected by the connection control means. To read the output signal of the amplifier to the first output line, and set the first output line to a potential based on the first signal;
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the first output line is supplied to an input of the amplifier, and an input of the amplifier is connected to the first signal. Potential based on
After the reset, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the first output line.
Further, the photoelectric conversion device of the present invention includes a plurality of photoelectric conversion pixels arranged in one line or two-dimensional shape, including an amplifying means for inputting, amplifying, and outputting the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
Each of the output units of the plurality of amplifying units of the plurality of photoelectric conversion pixels arranged in one line Of the plurality of photoelectric conversion pixels connected one by one or arranged two-dimensionally, one each for the output part of the plurality of amplifying means of the plurality of photoelectric conversion pixels of each line in one arrangement direction. A plurality of commonly connected first output lines;
A plurality of amplifying means having a negative gain connected to the plurality of first output lines one by one;
Connection control means for controlling connection between an output section of the amplifier means and the first output line;
A second output line for commonly outputting signals from the plurality of amplifier means,
A plurality of transfer switch means for transferring signals from the plurality of amplifier means to the second output line;
A horizontal scanning circuit that controls the plurality of transfer switch units so that signals from the plurality of amplifier units are transferred to the second output line in a time-series manner,
In a state where the output section of the amplifier means and the first output line are not connected, the first signal is amplified by the amplification means and then read out to the first output line,
Thereafter, an output signal of the amplifier is read out to the first output line by connecting an output section of the amplifier and the first output line, and the first output line is connected to the first signal. Potential based on
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the first output line is supplied to an input of the amplifier, and an input of the amplifier is connected to the first input. Set the potential based on the signal,
After the reset, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the first output line.
Further, the method for driving a photoelectric conversion device according to the present invention includes a photoelectric conversion pixel including an amplification unit that inputs, amplifies and outputs the accumulated photoelectric conversion signal, a unit that resets the photoelectric conversion pixel, and an output unit of the amplification unit. An output line connected to the amplifier, the output line and the input unit are capacitively coupled, and an amplifier is connected between the input unit of the amplifier and a predetermined potential, and the potential of the input unit of the amplifier is set to the predetermined potential. And a switch that selectively switches to a floating potential and a connection control unit that controls connection between the output unit of the amplifier and the output line.
The first signal is supplied to the amplifying unit in a state where the potential of the input unit of the amplifier is set to the predetermined potential by the switch, and the output unit and the output line of the amplifier are disconnected by the connection control unit. And then read out to the output line,
After that, the switch controls the potential of the input section of the amplifier to a floating potential and sets the potential of the input section of the amplifier to the floating potential, and connects the output section of the amplifier to the output line by the connection control means. Read the output signal of the amplifier to the output line, and set the output line to a potential based on the first signal;
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the output line is supplied to an input of the amplifying unit, and an input of the amplifying unit is set to a potential based on the first signal. Set to
After the reset, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the output line.
[0017]
【Example】
[First embodiment]
FIG. 1 is an equivalent circuit diagram of a two-dimensional photoelectric conversion device, taking a 2 × 2 pixel that best represents the features of the present invention as an example. 6, the elements having the same reference numerals as those in FIG. 6 are indicated by the same reference numerals and have the same functions, and the description is omitted.
[0018]
In FIG. 1, reference numeral 22 denotes a Darlington-type bipolar transistor of an amplifier, and 23 denotes a MOS transistor for a constant current source. The Darlington-type bipolar transistor 22 and the MOS transistor 23 form an emitter follower 35. In FIG. 1, the gate 23 is a reference intermediate potential V_VCAnd 24 is a coupling capacitance for capacitively coupling the input base portion of the emitter follower and the output line 5, 25 is a capacitance of the base of the Darlington bipolar transistor 22, 26 is a P-type MOS transistor for controlling the base potential thereof, 27 is a MOS transistor for switching and connecting the output part of the emitter follower as a switch and the output part 5, 28 is a terminal for applying a pulse φBR to the gate of the MOS transistor 26, and 29 is a MOS transistor 27. Terminal for applying a negative feedback pulse φFB to the gate of_BRPower supply terminal.
[0019]
FIG. 2 is a pulse timing chart for explaining the operation of the two-dimensional photoelectric conversion device according to the first embodiment shown in FIG. The process in which the elements in each row accumulate the optical carriers and are sequentially selected is the same as in the case shown in FIG. 6, and FIG. 2 shows a timing chart for driving one row.
[0020]
First, the drive pulse φR is set to the intermediate level V_VCTo High, the output V1 of the vertical shift register 34 is High, and the output of the pixel in the selected row is read out to the output line 5 in a floating state. At this time, since the pulse φBR at the terminal 28 is Low, the PMOS transistor 26 is turned ON, and the base of the bipolar transistor 22 is set at V_BRThe output of the emitter follower 35 composed of the Darlington type bipolar transistor 22 and the MOS transistor 23 is also fixed to (V_BR−1.2 V), but for simplicity, the output of the emitter follower 35 is equal to the reference potential V._VCAnd When the driving pulse φR returns to the intermediate level and the pixel reading is completed, the voltage of the output line 5 becomes V_VC+ V₁Then, the pulse φBR is set to High, the base of the bipolar transistor 22 is set in a floating state, the pulse φFB of the terminal 29 is changed from Low to High, and the output section of the emitter follower 35 and the output line 5 are connected. Conduct. The potential of the output line 5 is V_VC+ V₁To V_VC+ V₂, But this V₂Has the following values:
[0021]
Assuming that the value of the coupling capacitance 24 is C0 and the value of the parasitic capacitance 25 is C1, the output value of the emitter follower 35 receives the potential change of the output line 5 through the coupling of the coupling capacitance 24._VCFrom [C0 / (C0 + C1)] · (V₂-V₁) Only change.
The value after the change is V_VC+ V₂Because
V_VC+ [C0 / (C0 + C1)] · (V₂-V₁) = V_VC+ V₂
Than,
V₂= − (C0 / C1) · V₁
It becomes.
[0022]
V₁Is the output potential of the pixel, an output multiplied by a gain of-(C0 / C1) appears from the emitter follower 35 by performing the above operation. The output of the emitter follower 35 is stored in the storage capacitor 7 through the transistor 8 while the pulse φT of the terminal 19 is High, and the MOS 10 is turned on and the preamplifier 11 Transfer to
[0023]
Here, assuming that the parasitic capacitance of the horizontal output line 9 is CH and the capacitance of the storage capacitor 7 is CT, the capacitance is divided by CT / (CH + CT) at the time of transfer to the preamplifier 11, as in the conventional case. Is set to be (CH + CT) / CT, it is possible to just compensate for the signal drop due to the capacity division. In addition, the capacitance CT of the storage capacitor 7 is usually a capacitance of several pF, but C0 can be set to about several hundred fF. Therefore, for one pixel, the amount of electric charge flowing at the time of reading can be made smaller than before. Since the destruction of pixel signals is reduced, the S / N ratio at the time of pixel output can be increased.
[0024]
[Second embodiment]
FIG. 3 is a drive timing chart for explaining a second embodiment of the present invention using the two-dimensional photoelectric conversion device of FIG. In the second embodiment, as shown in FIG. 3, in the operation of the pixel as compared with the first embodiment, reset, accumulation of external light noise N, accumulation of external light noise N in the pixel, LED light and external light noise Are stored in the pixel, the pixel carrier signal is read out, and are sequentially executed in time series.
[0025]
When the two-dimensional photoelectric conversion device is used for photometry as an image sensor, a specific required optical signal and an unnecessary signal such as external light may be mixed. For example, there is a case where the light amount or the spectrum of the LED light is measured under the condition that external light enters.
[0026]
Conventionally, when it is desired to remove the external light component, only the external light component is first received and read, and the output of each pixel is written into a separately prepared memory. Next, a method has been adopted in which the light obtained by adding the LED light to the external light is received and read, and the difference between the external light component and the external light component written in the memory is obtained.
[0027]
The second embodiment according to the present invention is a method for removing external light components without using a memory, which will be described in detail with reference to FIG.
[0028]
In the figure, the base of the pixel transistor 2 in the first row selected first by the output V1 of the vertical shift register 34 is changed to V when the driving pulse φR is Low as in the conventional case._VCAnd reset when the drive pulse φR is High. The same applies to the second and subsequent lines.
[0029]
Next, only external light is accumulated in the base of the pixel transistor 2. The following is an operation that is a feature of the second embodiment of the present invention. When the first row is selected, the external light output potential is set to V, as in the read operation of the first embodiment described with reference to FIG._NThe pulse φBR is temporarily set to Low, then the pulse φFB is set to High temporarily, and the output of the emitter follower 35 obtained by multiplying the base accumulation potential by external light by −C0 / C1 is output to the output line 5. However, in the second embodiment, it is set so that C0 = C1. Therefore, the potential of the output line 5 becomes (V_VC-V_N). Since this output is a low impedance output by the emitter follower 35, when the pixel is reset by setting the drive pulse φR to High with respect to this potential, the base potential of the pixel becomes −V_NThe potential is defined by
[0030]
Next, light storage including the LED light to be measured is started. The base potential of the pixel is a voltage component V corresponding to external light._NAnd voltage V corresponding to LED light_LRises by the sum of_NIs the pixel potential −V before accumulation_NAre just canceled out, so that in the next pixel readout, the output from the pixel is the voltage V equivalent to the LED light._LAnd the external light component V_NDoes not enter. Voltage V corresponding to this LED light_LIs read and transferred in the same manner as in the first embodiment.
[0031]
In the operation of the second embodiment, the external light component V_NIs removed, and the variation component of each pixel output is also removed at the same time, so that a signal having a high S / N ratio can be obtained even when there is no external light.
[0032]
[Third embodiment]
Hereinafter, a third embodiment will be described. FIG. 4 is an equivalent circuit diagram showing the configuration of the third embodiment according to the present invention. In FIG. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description will be omitted.
[0033]
In FIG. 4, reference numeral 31 denotes a MOS transistor or a junction type transistor, and a source follower 36 is formed by the constant current source of the transistor 23 and the transistor 31. In the third embodiment shown in FIG. 4, the Darlington emitter follower 35 in FIG. 1 is replaced by a source follower 36, and the driving operation is the same as in the first and second embodiments. The third embodiment has advantages over the Darlington-type emitter follower 35 in that the input impedance is high, the temperature drift of the transistor element is small, and the number of manufacturing steps can be reduced when an IC is used. On the other hand, since it is necessary to keep the ratio of the capacitance value of the coupling capacitance 24 to the signal line 5 and the parasitic capacitance 25 having a large variation, the operation is more suitable for the operation according to the second embodiment than the first embodiment. .
[0034]
[Fourth embodiment]
Hereinafter, a fourth embodiment will be described. FIG. 5 is an equivalent circuit diagram that can implement the fourth embodiment according to the present invention. 1 or 4 are denoted by the same reference numerals, and detailed description is omitted.
[0035]
In FIG. 5, reference numeral 32 denotes an operational amplifier of an operational amplifier. In the fourth embodiment shown in FIG. 5, the Darlington-type emitter follower 35 in FIG. 1 is replaced with a voltage (voltage) follower 37, and the driving operation is the same as the second and third embodiments. Since the input voltage and the output voltage of the voltage follower 37 are almost the same, the voltage can be transferred to the storage capacitor 7 without reducing the carrier storage potential corresponding to the amount of light.
[0036]
In the first to fourth embodiments, the photoelectric conversion pixel according to the present invention uses an amplification type using a bipolar transistor. However, the present invention is not necessarily limited to this type, and a MOS type or SIT, JFET, and MOS transistor may be used. Even if the amplification type pixel is used, the amplification of each output line voltage according to the present invention can be performed in the same manner as long as the output line 5 can be brought into a floating state after the pixel output.
[0037]
If the reset level of the pixel can be defined by the output line potential, the operation of removing external light components and the like according to the present invention can be performed without using a memory. For a pixel using a MOS transistor or a JFET, it is easier to manufacture the photoelectric conversion device by applying the third embodiment according to the present invention as shown in FIG.
[0038]
Further, in the above embodiment, the example of the photoelectric conversion pixels of 2 rows × 2 columns has been described. However, the present invention can be applied to an image sensor and a line sensor. It is necessary to increase the speed of the scanning circuit and the switching of the accumulation of pixels extra by the time for accumulating and writing. However, the present invention can be applied to not only the example of the external light but also the calibration of the internal noise and the variation of the photoelectric conversion device, and the case where only the increment is detected when comparing two light amounts in the case of photometry.
[0039]
【The invention's effect】
As described above, according to the present invention, the photoelectric conversion pixelA high-performance, high-S / N photoelectric conversion device is provided because a signal from which a noise component contained in the image is removed can be obtained.be able to.
[Brief description of the drawings]
FIG. 1 is an equivalent circuit diagram of a photoelectric conversion device according to the present invention.
FIG. 2 is a timing chart for explaining an operation according to the first embodiment of the present invention.
FIG. 3 is a timing chart for explaining an operation according to a second embodiment of the present invention.
FIG. 4 is an equivalent circuit diagram illustrating a photoelectric conversion device according to a third embodiment of the present invention.
FIG. 5 is an equivalent circuit diagram illustrating a photoelectric conversion device according to a fourth embodiment of the present invention.
FIG. 6 is an equivalent circuit diagram of a conventional photoelectric conversion device.
FIG. 7 is a timing chart illustrating an operation of a conventional photoelectric conversion device.
[Explanation of symbols]
1 pixel
2 Bipolar transistor
3 PMOS transistor
4 capacity
5 Output line
6 MOS transistors
7 capacity
8 MOS transistors
9 Output line
10 MOS transistor
11 Amplifier
12 Output terminal
13 MOS transistor
14 Drive line
15 Drive pulse line
16 MOS transistors
17, 18, 19, 20, 21 pulse input terminal
22 Darlington-type bipolar transistor
23 MOS transistor
24 capacity
25 capacity
26 PMOS transistor
27 MOS transistor
28, 29, 30 Pulse input terminal
31 MOS or junction type FET
32 operational amplifier

Claims (7)

A photoelectric conversion pixel including amplification means for inputting, amplifying and outputting the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
An output line connected to an output section of the amplification means,
An amplifier in which the output line and the input unit are capacitively coupled;
A switch connected between an input portion of the amplifier and a predetermined potential, and selectively switching a potential of the input portion of the amplifier to the predetermined potential and a floating potential;
Including connection control means for controlling the connection between the output unit of the amplifier and the output line,
The first signal is supplied to the amplifying unit in a state where the potential of the input unit of the amplifier is set to the predetermined potential by the switch, and the output unit and the output line of the amplifier are disconnected by the connection control unit. And then read out to the output line,
After that, the switch controls the potential of the input section of the amplifier to a floating potential and sets the potential of the input section of the amplifier to the floating potential, and connects the output section of the amplifier to the output line by the connection control means. Read the output signal of the amplifier to the output line, and set the output line to a potential based on the first signal;
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the output line is supplied to an input of the amplifying unit, and an input of the amplifying unit is set to a potential based on the first signal. Set to
A photoelectric conversion device, wherein after resetting, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the output line. 2. The photoelectric conversion device according to claim 1, wherein the amplifier is an emitter follower, a source follower, or an operational amplifier. A photoelectric conversion pixel including amplification means for inputting, amplifying and outputting the accumulated photoelectric conversion signal,
Means for resetting the photoelectric conversion pixels,
An output line connected to an output section of the amplification means,
Amplifier means having a negative gain connected to the output line;
Including connection control means for controlling the connection between the output unit and the output line of the amplifier means,
In a state in which the output unit of the amplifier unit and the output line are not connected, the first signal is amplified by the amplifier unit and then read to the output line,
Thereafter, an output signal of the amplifier is read out to the output line by connecting an output section of the amplifier and the output line, and the output line is set to a potential based on the first signal,
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the output line is supplied to an input of the amplifier, and an input of the amplifier is set based on the first signal. Set to potential,
A photoelectric conversion device, wherein after resetting, a second signal is accumulated by photoelectric conversion, and the second signal is amplified by the amplifying means and read out to the output line. 4. The photoelectric conversion device according to claim 3 , wherein the amplifier means is configured to provide an emitter follower or a source follower or an operational amplifier capacitively coupled to the output line and an input section of the emitter follower or the source follower or the operational amplifier. And a switch for selectively switching between the voltage and the floating potential. A plurality of photoelectric conversion pixels arranged in one line or two-dimensionally, including amplifying means for inputting, amplifying and outputting the accumulated photoelectric conversion signals,
Means for resetting the photoelectric conversion pixels,
One array of the plurality of photoelectric conversion pixels connected one by one to each of the output units of the plurality of amplifying units of the plurality of photoelectric conversion pixels arranged in one line, or the two-dimensionally arranged photoelectric conversion pixels A plurality of first output lines commonly connected one by one to output units of a plurality of amplifying units of a plurality of photoelectric conversion pixels of each line in the direction;
A plurality of amplifiers each having an input unit capacitively coupled to each of the plurality of first output lines;
A switch connected between an input portion of the amplifier and a predetermined potential, and selectively switching a potential of the input portion of the amplifier to the predetermined potential and a floating potential;
Connection control means for controlling connection between the output unit of the amplifier and the first output line capacitively coupled to the input unit;
A second output line for commonly outputting signals from the plurality of amplifiers,
A plurality of transfer switch means for transferring signals from the plurality of amplifiers to the second output line;
A horizontal scanning circuit that controls the plurality of transfer switch units so that signals from the plurality of amplifiers are transferred to the second output line in a time-series manner,
The first signal is output in a state where the potential of the input section of the amplifier is set to the predetermined potential by the switch, and the output section of the amplifier is not connected to the first output line by the connection control means. Amplifying by the amplifying means and then reading out to the first output line,
Thereafter, the switch controls the potential of the input portion of the amplifier to a floating potential, and sets the potential of the input portion of the amplifier to a floating potential. To read out the output signal of the amplifier to the first output line, and set the first output line to a potential based on the first signal,
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the first output line is supplied to an input of the amplifier, and an input of the amplifier is connected to the first signal. Potential based on
A photoelectric conversion device, wherein a second signal is accumulated by photoelectric conversion after the reset, and the second signal is amplified by the amplifying means and read out to the first output line. A plurality of photoelectric conversion pixels arranged in one line or two-dimensionally, including amplifying means for inputting, amplifying and outputting the accumulated photoelectric conversion signals,
Means for resetting the photoelectric conversion pixels,
One of the plurality of photoelectric conversion pixels arranged in one line is connected to each of the output units of the plurality of amplifying units, or one of the plurality of two-dimensionally arranged photoelectric conversion pixels is arranged in one array direction. A plurality of first output lines commonly connected one by one to output units of a plurality of amplifying units of a plurality of photoelectric conversion pixels of each line,
A plurality of amplifying means having a negative gain connected one by one to each of the plurality of first output lines;
Connection control means for controlling connection between the output section of the amplifier means and the first output line;
A second output line for commonly outputting signals from the plurality of amplifier means,
A plurality of transfer switch means for transferring signals from the plurality of amplifier means to the second output line;
A horizontal scanning circuit that controls the plurality of transfer switch means so that signals from the plurality of amplifier means are transferred to the second output line in a time-series manner,
In a state where the output unit of the amplifier unit and the first output line are not connected, the first signal is amplified by the amplification unit and then read to the first output line,
Thereafter, an output signal of the amplifier is read out to the first output line by connecting an output section of the amplifier and the first output line, and the first output line is connected to the first signal. Potential based on
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the first output line is supplied to an input of the amplifier, and an input of the amplifier is connected to the first input. Set the potential based on the signal,
A photoelectric conversion device, wherein a second signal is accumulated by photoelectric conversion after the reset, and the second signal is amplified by the amplifying means and read out to the first output line. A photoelectric conversion pixel including amplification means for inputting, amplifying and outputting the accumulated photoelectric conversion signal, means for resetting the photoelectric conversion pixel, and connection to an output section of the amplification means The output line, the amplifier in which the output line and the input section are capacitively coupled, and connected between the input section of the amplifier and a predetermined potential, and set the potential of the input section of the amplifier to the predetermined potential and floating. A switch that selectively switches to a potential in a state, and a connection control unit that controls connection between an output unit of the amplifier and the output line;
The first signal is supplied to the amplifying unit in a state where the potential of the input unit of the amplifier is set to the predetermined potential by the switch, and the output unit and the output line of the amplifier are disconnected by the connection control unit. And then read out to the output line,
After that, the switch controls the potential of the input section of the amplifier to a floating potential and sets the potential of the input section of the amplifier to the floating potential, and connects the output section of the amplifier to the output line by the connection control means. Read the output signal of the amplifier to the output line, and set the output line to a potential based on the first signal;
Thereafter, the photoelectric conversion pixel is reset, an output signal of the amplifier read out to the output line is supplied to an input section of the amplification section, and an input section of the amplification section is set to a potential based on the first signal. Set to
A method for driving a photoelectric conversion device, comprising: accumulating a second signal by photoelectric conversion after resetting; amplifying the second signal by the amplifying unit; and reading out the amplified signal on the output line.

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