JP4857996B2 - Imaging device - Google Patents

Description

  The present invention relates to an image pickup apparatus using a solid-state image pickup device such as a CMOS image sensor or a CCD image sensor, and more particularly to an image pickup device capable of performing shooting with an optimized solid-state image pickup device according to environmental conditions.

Conventionally, as a solid-state imaging device used in an imaging apparatus, a photodiode that performs photoelectric conversion for each of a plurality of pixels that form an imaging unit, a readout transistor that reads out a signal charge generated by the photodiode, and a readout signal charge Various types of CMOS image sensors are provided which are provided with an amplifying transistor for converting the pixel signal into a pixel signal, a reset transistor for resetting signal charges, a selection transistor for selecting a pixel to be read out, and the like.
However, such a CMOS image sensor has a problem of afterimage. In general, an afterimage occurs due to a charge remaining due to insufficient shutter at the previous timing or a transfer failure at the time of reading accumulated charge, and deteriorates linearity at low illuminance (signal amount is small).
In particular, as the light receiving area of the photoelectric conversion unit increases, such as a large format sensor used for a single-lens reflex camera or the like, countermeasures for afterimages are necessary.

As measures for this, (1) increase the L length of the read (= transfer) gate, (2) widen the read pulse width at the time of read, (3) lower the overflow barrier (reduce the amount of accumulated charge), 4) There is a countermeasure such as increasing the applied voltage at the time of reading (transfer) to lower the potential under the transfer gate.
However, in the case of (1), the gate is extended to the photoelectric conversion unit side, the vignetting of light on the gate is increased (= the area of the photoelectric conversion unit is reduced), and as in the case of (3). As a result, the amount of stored charge decreases.
In recent years, high-speed shooting has been demanded to capture still images clearly during moving image shooting, and the input clock frequency has increased and the frame rate has increased. For this reason, in each pixel column, it is not preferable to widen the readout pulse width both at the time of shutter and at the time of readout as shown in (2) because this leads to a delay in operation. As for (4), the boosted power (EX: 3 V or more) is supplied only to the applied voltage when the readout (transfer) Tr in the pixel is ON, and other pixels Tr (reset Tr, selection Tr, pixel power) Has proposed a conventional technique of applying a power supply voltage (EX: 3 V) used in CMOS logic (peripheral circuit) (see, for example, Patent Document 1).
International Publication WO2003-085964

By the way, in the prior art, there is an image pickup apparatus configured to give temperature characteristics to a negative voltage applied to a transfer gate in order to prevent dark current. In this case, a high level (power supply voltage) and a low level (negative voltage) are applied to the oxide film of the transfer gate, but the potential difference increases as the temperature increases. This causes a defect in the reliability of the oxide film of the inverter that drives the transfer gate.
In addition, when the oxide film withstand voltage of the drive circuit cannot be tolerated, there is a measure to make the gate oxide film thicker than other regions, but this increases the number of process steps and leads to cost increase. End up.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging apparatus capable of optimizing afterimage prevention and white point prevention without increasing stress on the gate oxide film.

  In order to achieve the above-described object, the imaging apparatus of the present invention has a detection unit that detects a change in a predetermined physical quantity, a unit signal generation unit that outputs a predetermined unit signal, and a local voltage that is different from a normal operating voltage. It has a local voltage generation part to generate, and a voltage control part which supplies a local voltage to the predetermined terminal which outputs the unit signal based on the change of the physical quantity detected by the detection part.

According to the imaging apparatus of the present invention, since the local voltage is supplied to the predetermined terminal for outputting the unit signal based on the change in the predetermined physical quantity detected by the detection unit, the change in various environmental conditions can be achieved. Accordingly, it is possible to optimize the drive voltage supplied to each unit. In particular, the unit signal that controls a specific part, not the entire voltage level, can be individually controlled by the local voltage, so the optimal control operation for individual parts that require subtle control while suppressing overall power consumption Can be secured.
Therefore, for example, it is possible to control the boosted voltage applied to the transfer transistor or the like in the pixel for reducing the afterimage and the negative voltage for preventing the increase of the white point due to the dark current so that the potential difference becomes substantially equal. The afterimage of the pixel and the white spot can be optimized without increasing the stress on the gate oxide film, and a countermeasure such as increasing the thickness of the oxide film becomes unnecessary.

Also, a plurality of detection units, unit signal generation units, and local voltage generation units are provided, and a detection unit, a unit signal generation unit, and a local voltage generation unit are provided for each of a plurality of unit components arranged in a predetermined order. By arranging these, it is possible to supply an optimum local voltage to each part of the apparatus.
Further, by changing the plurality of local voltages in correlation with each other according to the change in the physical quantity, it is possible to further optimize the plurality of local voltages.
In addition, by setting the physical quantity detection range in the detection unit, it is possible to detect the physical quantity with a simple configuration. For example, by using a hysteresis comparator, stable detection resistant to noise or the like near the threshold is performed. It becomes possible. In addition, the voltage control unit can realize an appropriate operation by changing the local voltage according to the synchronization signal.
Further, by using a temperature detection circuit using a diode as the detection unit, simple and appropriate temperature measurement can be performed, and appropriate voltage control can be performed with respect to a change in temperature. Specifically, this can be realized by providing an output voltage setting unit that reflects the detection signal of the temperature detection circuit in the output voltage, or by providing a reference voltage unit that reflects the detection signal of the temperature detection circuit in the reference voltage.
In addition, the voltage control unit can supply a plurality of local voltages that maintain a voltage difference to a predetermined terminal, thereby maintaining a proper breakdown voltage of the insulating film and obtaining a stable operation.

FIG. 1 is a schematic circuit diagram showing an example of a pixel and a drive circuit (vertical driver unit) of an imaging device (CMOS image sensor) according to an embodiment of the present invention, and FIG. 2 shows a pixel driving method according to the present embodiment. It is a timing chart which shows.
In FIG. 1, the CMOS image sensor includes an imaging unit in which a large number of pixels are two-dimensionally arranged and a peripheral circuit unit arranged outside the imaging unit, and each pixel 100 in the figure is included in the imaging unit. The vertical (V) driver unit 200 is provided in the peripheral circuit unit.
Each pixel 100 includes a photodiode as a photoelectric conversion unit, a read transistor (transfer gate) that transfers a signal charge generated by the photodiode to an FD (floating diffusion), and a potential of the FD by detecting the potential of the FD. It includes an amplification transistor that generates a signal, a selection transistor that selects a pixel row that outputs a pixel signal, a reset transistor that resets the FD, and the like. In FIG. 1, only the photodiode 101 and the transfer gate 102 are shown in each pixel.

In addition, the V driver unit 200 incorporates a level shift circuit 210 as a local voltage generation circuit that switches between power supplies to be applied at the time of ON and OFF, and a transfer pulse TRG is applied to the transfer gate of the row selected by the decoder 220. As the input, VOUT1 (boost) and VOUT2 (negative voltage) are input. Here, VOUT1 and VOUT2 are respectively applied to the inverter 230 that drives the transfer gate, and the difference voltage affects the withstand voltage of the oxide film.
The decoder 220 supplies a reset signal RST to the reset transistor of each pixel via the buffer 240, and supplies a selection signal SEL to the selection transistor of each pixel via the buffer 250.

Next, the operation of each pixel will be described along the timing chart shown in FIG.
First, a pixel is selected by a selection signal SEL, and a voltage at the time of no signal is output after a reset signal RST. Next, after a predetermined charge accumulation time of the photodiode has elapsed, the transfer gate (TRG) is turned on, and the signal voltage is read out. Then, CDS (correlated double sampling) is performed by taking the difference between this signal voltage and the voltage at the time of no signal, and a signal in a state in which the characteristic difference between pixels is removed is output.
In this example, in such a signal read operation, one feature is that the high level of the voltage applied to the transfer gate is movable depending on the temperature. Specifically, the voltage applied to the transfer gate in the pixel is higher than the voltage applied when the other pixel transistors (reset transistor and selection transistor) are ON (for example, when the transfer gate is ON: 3.2 V). Other pixel transistors are ON: 3V, etc.).
As another feature of this example, the transfer gate is driven by making the potential difference applied to the transfer gate constant by considering the temperature characteristics of the negative voltage applied to the transfer gate for enhancing pinning. Improves reliability of inverter gate oxide. Note that the applied voltage when the reset transistor and the selection transistor are ON is equal to (for example, 3 V) the power supply voltage of the CMOS logic circuit (peripheral circuit portion).

Next, FIG. 3 is an explanatory diagram showing the intra-pixel potential distribution of the image sensor according to the present embodiment, showing the arrangement of each element in the horizontal direction and the potential in the vertical direction. In the figure, TRG is a transfer gate voltage, RST is a reset gate voltage, VDD is a pixel driving power supply voltage, AMP is an amplification gate (= FD) voltage, SEL is a selection gate voltage, VSL is a vertical signal line voltage, and LogicVDD is a logic circuit. The figure shows a state in which the transfer gate voltage is boosted.
In the case of a CMOS sensor, the empty potential of the photodiode portion (= the deep portion potential of the photodiode portion) is about 1.0 to 2.0 V, so that the higher the applied voltage when the transfer gate is turned on, the lower the transfer gate is. This lowers the potential and facilitates reading.
In this case, since the potential at the deep part of the FD is equal to the potential applied to the reset transistor, the potential when the transfer gate is ON is deeper than the deep part potential of the FD, so that electrons accumulate under the transfer gate, resulting in an afterimage. Concerned. However, since the pulse for turning on the transfer gate is instantaneous, the boosted voltage applied to the transfer gate is increased to such an extent that no afterimage is produced.

FIG. 4 is an explanatory diagram showing the dependence of input / output linearity on the read power supply voltage and temperature at low illuminance in the CMOS sensor of this example. The horizontal axis represents the accumulation time, and the vertical axis represents the output. ) Is a partially enlarged view of FIG.
In this figure, as shown by the arrow direction in the figure, the linearity at the time of low illuminance improves as the read power supply voltage increases. In addition, after-electrons are thermally excited at a high temperature, an afterimage that could not be seen may occur due to a potential barrier at a low temperature.

FIG. 5 is a circuit diagram showing a first example of a charge pump circuit used for the level shift circuit 210 in this example.
The charge pump circuit used in this example is a combination of a boost charge pump circuit and an inverting charge pump circuit.
First, the step-up charge pump circuit 300A includes an oscillation circuit 301, an amplifier 302, switches SW1 to SW4, voltage dividing resistors R1 and R2, a pump capacitor (pump capacity) C _P1 , an output capacitor C _OUT1 , an inverter 303, and temperature characteristics. consists of a per reference voltage circuit 304 or the like, the power supply voltage Va1 by the amplifier 302 is applied to both ends of the pump capacitor _{C P1} through the switch SW1, SW4, output one end of the pump capacitor _{C P1} via the switch SW2 The other end of the capacitor _COUT1 is connected to the ground via the switch SW3.
Then, the oscillation circuit 301, an inverter 303, and the switching operation by the switch SW1 to SW4, and electric charge from the amplifier 302 to the pump capacitor _{C P1,} smoothes the boosted output by the output capacitor _{C OUT1,} the voltage Output as output _VOUT .
Further, in this circuit, the output voltage _VOUT1 is divided by resistors R1 and R2, the divided voltage and the reference voltage _Vref0 by the reference voltage circuit 304 with temperature characteristics are compared by the amplifier 302, and the output voltage Va1 of the amplifier 302 is compared. Is used as a power source for the pump capacitor C _P1 .

Next, the inverting charge pump 300B, the reference voltage source 311, amplifier 312, switch SW5～SW8, voltage dividing resistors R3, R4, pump capacitor (pump _{capacity) C P2,} the output capacitor _{C OUT2,} inverters 313 and 314 and step-up charge pump circuit 300A and the shared oscillator circuit 301 is constituted by a temperature characteristic with the reference voltage circuit 304 or the like, one end of the pump capacitor _{C P2} is grounded via a switch SW5 (GND), the switches SW6 is connected to an output capacitor _{C OUT2} through, the other end is connected to the driving voltage Vdd through the switch SW7, which is connected to the output of the amplifier 312 through the switch SW8.
Then, first, charge the charge pump capacitor _{C P2} by connecting between Vdd and GND by a switch SW5, SW7, then connects the switch SW8 to output voltage Va2 of the amplifier 312, an inverse-end switch By connecting to SW6, a negative voltage output _VOUT2 is generated.
In this circuit, the resistors R3 and R4 are provided between the output voltage VOUT2 and the reference voltage (Vrefout) from the reference voltage source 311 described above, and the divided voltage is output to the inverting input of the amplifier 312. The reference voltage Vref0 used for the boost type is applied to the non-inverting input of the amplifier 312. By using the output Va2 of the amplifier as a voltage level of the capacitance C _P2, it performs a reverse operation.

This example is characterized in that the reference voltage Vref0 is shared and temperature characteristics are provided. FIG. 6 is a circuit diagram showing a reference voltage circuit used in this example. As illustrated, this circuit includes a constant current circuit 321, a diode 322, an amplifier 323, a transistor 324, voltage dividing resistors R5 and R6, and the like. The diode 322 and the constant current circuit 321 generate a temperature-dependent voltage Vf, and then level-shifts by voltage division of the resistors R5 and R6 to generate Vref0.
FIG. 7 shows the temperature characteristics of the diode measured actually (where I = 10 μA). As shown in the figure, Vf decreases as the temperature Ta increases. FIG. 8 shows a graph for calculating the temperature characteristics of Vref0 when the value of R5 = R6 (I = 10 μA) is taken.
Further, FIG. 9 shows output voltage characteristics in the charge pump circuit shown in FIG. 5 when such a reference voltage Vref0 with temperature characteristics is used.
Here, as setting examples, R1 = R3 = 100 kΩ, R2 = 120 kΩ, R4 = 450 kΩ, and Vrefout = 2V were measured.
As shown in the figure, it can be seen that the voltage difference applied to the transfer gate (TRG) fluctuates in substantially the same manner as the boosted voltage and the inverted voltage fluctuate with the correlation of Vref0. As a result, the reliability of the gate due to potential fluctuation at the time of temperature change is not impaired.

FIG. 10 is a circuit diagram showing a second example of the charge pump circuit used for the level shift circuit 210 in this example.
As shown in the drawing, this charge pump circuit is basically the same as the charge pump circuit shown in FIG. 5, but in this example, the temperature detection is shared between the boosting charge pump circuit and the inverting charge pump circuit. A circuit 331 is mounted, and each of the voltage dividing resistors R1, R2, R3, and R4 is a variable division type, and output voltage setting units 332 and 333 corresponding to temperature detection values are provided. The rest of the configuration is the same as that shown in FIG. 5, and the same components are denoted by the same reference numerals and description thereof is omitted.

FIG. 11 is a circuit diagram showing details of the temperature detection circuit 331 and the output voltage setting units 332 and 333.
In this figure, the temperature detection circuit 331 has a temperature range to be detected set in three stages and depends on the voltage dividing resistors Ra, Rb, Rc for obtaining the divided voltages V1, V2 by the fixed potential Vref and the temperature. Comparison between the constant current circuit 341 and the diode 342 for measuring the voltage value Vtemp to be performed, the amplifiers 343 and 344 that compare the voltage value Vtemp that depends on temperature and the fixed voltage values V1 and V2, and the amplifiers 343 and 344 An AND circuit 345 that generates a value combination signal and a D-type flip-flop circuit 346 that latches each combination signal based on the synchronization signal XVS. Note that the synchronization signal XVS used here is a vertical synchronization signal that becomes active at the head of an image frame. As a result, the change in the output voltage can be designed to change during the blanking period, and shading does not occur without voltage fluctuation during the effective period.
The output voltage setting unit 332 is a switch circuit that selectively short-circuits the divided resistors R, 3R, and 4R provided between the divided resistors R1 and R2 and the divided resistors R, 3R, and 4R using a latch signal. 347.
The output voltage setting unit 333 is a switch circuit that selectively short-circuits the divided resistors R, 2R, and 4R provided between the divided resistors R3 and R4 and the divided resistors R, 2R, and 4R using a latch signal. 348.

In such a configuration, the temperature detection circuit 331 uses the temperature characteristic of the diode as shown in FIG. 7, and compares the voltage value Vtemp that changes with the environmental temperature with the divided voltages V1 and V2 by the fixed potential Vref. Here, the fixed potential Vref is a voltage source that is generated from a bandgap reference or the like and has little temperature dependence. In the illustrated example, an example in which the output voltage is changed in three stages as the temperature range is shown, but it is not limited to this.
The temperature range is set by setting the threshold values of the diode forward direction Vtemp to V1 and V2. At that time, when Vtemp> V1, V2 <Vtemp <V1, and Vtemp <V2, the settings (1), (2), and (3) are selected and output in synchronization with the XVS signal.
This output can change the charge pump output voltages VOUT1 and VOUT2 in accordance with the following formulas 1 to 4 by changing the resistance division ratio of the output voltage setting unit (note that the formulas 2 and 4 are expressed by the formula (1)). It is an expression for the condition).

VOUT1 = (R1 + R2 ′) / R1 * Vref0 ...... Formula 1
R2 ′ = R2 + 3R + 4R ...... Formula 2
VOUT2 = (R3 + R4 ′) / R3 * Vref0−R4 ′ / R3 * Vrefout ...... Equation 3
R4 ′ = R4 + R + 2R (Formula 4)
Since this voltage change occurs in synchronization with XVS, it is designed to change within the blanking period, so that shading is not caused without voltage fluctuation in the OPB region for determining the black level and the effective period.
FIG. 12 shows an example of output voltage characteristics. The calculation result of the output voltage when R1 = R3 = R4 = 100 kΩ, R2 = 400 kΩ, R = 10 kΩ, Vref0 = 0.5 V, and Vrefout = 1.5 V is shown. Show. This shows that the potential difference is kept constant.

FIG. 13 is a circuit diagram showing a third example of the charge pump circuit used in the level shift circuit 210 in this example.
As shown in the figure, this charge pump circuit is basically the same as the charge pump circuit shown in FIG. 10, but in this example, the result of the temperature detection circuit 331 is fed back to the reference voltage. In this configuration, the resistance division ratio is selected by a signal from the temperature detection circuit 331 for Vref0 generated by resistance division of R7 and R8 from a voltage such as a band gap. The rest of the configuration is the same as that shown in FIG. 10, and the same components are denoted by the same reference numerals and description thereof is omitted.

FIG. 14 is a circuit diagram showing details of the temperature detection circuit 331 and the reference voltage circuit 304.
As shown in the figure, the temperature detection circuit 331 is similar to the example shown in FIG. In addition, the reference voltage circuit 304 is a switch circuit 351 that selectively short-circuits the divided resistors R, 2R, and 4R provided between the divided resistors R7 and R8 and the divided resistors R, 2R, and 4R using a latch signal. And a transistor 352 for controlling a power supply voltage applied to the dividing resistor, and an amplifier 353 for applying a voltage from the BGR voltage circuit 354 to the gate of the transistor 352. Here, the BGR voltage circuit 354 is a circuit that generates and outputs a silicon bandgap reference (BGR) voltage, and is used as an output source of a voltage that is not affected by a change in temperature. However, other reference voltage generation sources may be used.
The operation of this circuit is the same as the circuit shown in FIG. 11. For example, if BGR = 1.25V, R7 = 40kΩ, R8 = 60kΩ, and R = 10kΩ as a setting example, the potential difference is almost constant at about 4V. .

FIG. 15 is a circuit diagram showing another example of the temperature detection circuit.
As shown in the figure, this circuit is different from the above-described example in the voltage dividing circuit of the fixed potential, and resistors Rd and Re are newly added as divided resistors, and a switch 361 that short-circuits the resistors Rd and Re. , 362 are provided, and these are opened and closed in accordance with the outputs of the amplifiers 343 and 344 so as to have a hysteresis characteristic, thereby forming a hysteresis comparator configuration that is hardly affected by noise in the vicinity of the threshold value. The other temperature detection circuit configurations are the same as those shown in FIG.
In the above example, the local voltage power source is mounted on the same chip of the solid-state imaging device. However, the same configuration is possible with an externally supplied power source. In that case, the temperature detection circuit may be provided inside the chip or outside.
Although the above description has been made using a charge pump circuit as a circuit for generating a local voltage, a chopper type DC / DC converter using a coil can be realized using a similar configuration.
Further, as a means for detecting the environmental change, a means for detecting a physical quantity other than the temperature (for example, the amount of received light) may be provided, and a local voltage at a necessary location may be controlled using the detection result. Of course, a configuration in which the signal voltage supplied to different parts according to a plurality of physical quantities such as temperature and light quantity is individually controlled is also possible.
Further, although the example in which the unit signal for changing the local voltage according to the environmental change is applied to the transfer gate pulse signal has been described, it can also be applied to other signals. Further, the synchronization signal is not limited to the vertical synchronization signal XVS described above, and can be appropriately changed according to the unit signal to be controlled.
Further, although the case where the present invention is applied to a CMOS image sensor has been described above, the present invention is not necessarily limited to a CMOS image sensor, and can be applied to an imaging apparatus such as a CCD image sensor.

It is a schematic circuit diagram which shows an example of the pixel and drive circuit of an imaging device (CMOS image sensor) by embodiment of this invention. 3 is a timing chart showing a pixel driving method in the CMOS image sensor shown in FIG. 1. It is explanatory drawing which shows the potential distribution in a pixel of the CMOS image sensor shown in FIG. It is explanatory drawing which shows the dependence with respect to the read power supply voltage and temperature of the input-output linearity at the time of the low illumination intensity in the CMOS image sensor shown in FIG. FIG. 2 is a circuit diagram showing a first example of a charge pump circuit used in the level shift circuit of the CMOS image sensor shown in FIG. 1. FIG. 6 is a circuit diagram showing a reference voltage circuit used in the charge pump circuit shown in FIG. 5. It is explanatory drawing which shows the temperature characteristic by measurement of the diode used with the reference voltage circuit shown in FIG. FIG. 7 is an explanatory diagram showing temperature characteristics of Vref0 when a value of R5 = R6 is taken in the reference voltage circuit shown in FIG. FIG. 6 is an explanatory diagram showing output voltage characteristics of the charge pump circuit shown in FIG. 5. FIG. 4 is a circuit diagram showing a second example of a charge pump circuit used in the level shift circuit of the CMOS image sensor shown in FIG. 1. FIG. 11 is a circuit diagram showing details of a temperature detection circuit and an output voltage setting unit of the charge pump circuit shown in FIG. 10. FIG. 11 is an explanatory diagram illustrating an example of output voltage characteristics of the charge pump circuit illustrated in FIG. 10. FIG. 6 is a circuit diagram showing a third example of a charge pump circuit used in the level shift circuit of the CMOS image sensor shown in FIG. 1. FIG. 14 is a circuit diagram showing details of a temperature detection circuit and a reference voltage circuit of the charge pump circuit shown in FIG. 13. FIG. 14 is a circuit diagram showing another example of the temperature detection circuit of the charge pump circuit shown in FIG. 13.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Pixel, 101 ... Photodiode, 102 ... Transfer gate, 200 ... V driver part, 210 ... Level shift circuit, 220 ... Decoder, 230, 303 ... Inverter, 300A ... Boost type charge pump Circuit, 300B... Inverting charge pump circuit, 301... Oscillation circuit, 302... Amplifier, 304... Reference voltage circuit with temperature characteristics, 331... Temperature detection circuit, SW1 to SW8. … Voltage divider resistor, C _P1 … pump capacitor, C _OUT1 … output capacitor.

Claims (6)

A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
Have a, a voltage control unit supplies a local voltage to a predetermined terminal for outputting the unit signal based on the change of the physical quantity detected by the detecting unit,
A plurality of detection units, unit signal generation units, and local voltage generation units are provided.
Imaging device. A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
A voltage control unit that supplies a local voltage to a predetermined terminal that outputs the unit signal based on a change in physical quantity detected by the detection unit;
The voltage control unit varies a plurality of local voltages in correlation with each other according to a change in the physical quantity.
Imaging device. A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
A voltage control unit that supplies a local voltage to a predetermined terminal that outputs the unit signal based on a change in physical quantity detected by the detection unit;
The detection unit includes a hysteresis comparator as means for setting the detection range of the physical quantity.
Imaging device. A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
A voltage control unit that supplies a local voltage to a predetermined terminal that outputs the unit signal based on a change in physical quantity detected by the detection unit;
The voltage control unit comprises means for varying the synchronization signal a local voltage
Imaging device. A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
A voltage control unit that supplies a local voltage to a predetermined terminal that outputs the unit signal based on a change in physical quantity detected by the detection unit;
The detection unit includes a temperature detection circuit using a diode ,
The voltage control unit includes a reference voltage unit that reflects a detection signal of the temperature detection circuit in a reference voltage.
Imaging device. A detection unit for detecting a change in a predetermined physical quantity;
A unit signal generator for outputting a predetermined unit signal;
A local voltage generator that generates a local voltage different from the normal operating voltage;
A voltage control unit that supplies a local voltage to a predetermined terminal that outputs the unit signal based on a change in physical quantity detected by the detection unit;
The voltage controller supplies a plurality of local voltages that maintain a voltage difference to a predetermined terminal.
請 Motomeko 1 imaging device according.

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