WO2013008644A1 - 撮像装置及び固体撮像装置の保護装置 - Google Patents
撮像装置及び固体撮像装置の保護装置 Download PDFInfo
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- WO2013008644A1 WO2013008644A1 PCT/JP2012/066649 JP2012066649W WO2013008644A1 WO 2013008644 A1 WO2013008644 A1 WO 2013008644A1 JP 2012066649 W JP2012066649 W JP 2012066649W WO 2013008644 A1 WO2013008644 A1 WO 2013008644A1
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- H—ELECTRICITY
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- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
- H04N25/71—Charge-coupled device [CCD] sensors; Charge-transfer registers specially adapted for CCD sensors
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- H—ELECTRICITY
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- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
- H04N25/71—Charge-coupled device [CCD] sensors; Charge-transfer registers specially adapted for CCD sensors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- 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
- H01L27/146—Imager structures
- H01L27/14601—Structural or functional details thereof
- H01L27/14603—Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- 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
- H01L27/146—Imager structures
- H01L27/14601—Structural or functional details thereof
- H01L27/14609—Pixel-elements with integrated switching, control, storage or amplification elements
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- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/60—Control of cameras or camera modules
- H04N23/65—Control of camera operation in relation to power supply
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
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Definitions
- the technology disclosed in this specification relates to an imaging device and a protection device for a solid-state imaging device.
- Some solid-state imaging devices can use a so-called electronic shutter function (charge sweeping operation toward the substrate) that sweeps generated charges toward the substrate by superimposing an electronic shutter pulse on the substrate voltage.
- the substrate voltage can adjust the saturation signal amount of the light receiving unit. By changing the substrate voltage according to the driving mode, the saturation signal amount necessary for each driving mode can be adjusted.
- the signal can be reset by applying a shutter pulse to the substrate voltage. Thereby, the exposure time can be adjusted.
- a driver pulse drive unit
- both the solid-state imaging device and the driver have operating voltage values (for example, required for other various circuits).
- the charge sweeping control controls the timing of the start of charge accumulation in the photoelectric conversion unit such as a photodiode, so that the driver circuit for the electronic shutter pulse in the driver
- the electronic shutter pulse is applied to the first polarity substrate (for example, an n-type substrate) via a wiring different from the transfer clock.
- a substrate voltage control circuit is connected to the substrate voltage terminal of the first polarity substrate, and a predetermined voltage (reverse bias voltage) is always applied to the first polarity substrate during operation.
- the electronic shutter pulse driver circuit When the charge is discharged, the electronic shutter pulse driver circuit outputs a pulse signal, and the voltage of this pulse signal is superimposed on the applied voltage of the substrate voltage control circuit, so that a reverse bias voltage stronger than normal is applied to the first. Applied to the polar substrate, the accumulated charge is swept away.
- a voltage range that can be taken between terminals or between terminals is defined as an absolute maximum rating.
- Such a rating is observed in a steady state, but may deviate from the standard when the power switch of the imaging apparatus is turned on / off, for example. Therefore, depending on the configuration of the electronic shutter pulse circuit between the driver and the solid-state imaging device, an abnormal voltage exceeding the absolute maximum rating may be applied to the substrate voltage terminal when the power is turned on or off, and the solid-state imaging device There is a concern of damage or deterioration.
- Japanese Patent Laid-Open No. 10-327360 discloses a protection circuit having a two-stage clamp circuit composed of a DC cut capacitor, a clamp diode, and a discharge resistor.
- the diode is connected in parallel with the resistor, and the anode end is connected to a reference potential (usually 0 V). That is, the diode is connected so as to be conducted by the negative voltage of the substrate voltage terminal.
- the capacitor of the second stage clamp circuit, the cathode end of the diode, and the connection point of the resistor are connected to the substrate voltage terminal.
- This turns on when the potential of the substrate voltage terminal exceeds the forward voltage drop of the diode (actually increases to the negative potential side) when the power is turned on or off, so the potential of the substrate voltage terminal is Clamped to approximately the forward drop of the diode. This can prevent a negative voltage lower than the rating from being applied to the substrate voltage terminal.
- the protection circuit described in Japanese Patent Laid-Open No. 10-327360 has a two-stage clamp circuit composed of a capacitor, a diode, and a resistor, at least six elements are required.
- a special and expensive diode such as a Schottky diode must be selected as the diode of the clamp circuit at the second stage.
- the electronic shutter drive pulse has been described. However, the same may occur with other drive pulses depending on the drive pulse supply circuit.
- an object of the present disclosure is to provide a technology capable of reducing the number of elements and alleviating restrictions on component selection in a protection device for a solid-state imaging device and an imaging device using the same.
- An imaging device includes a solid-state imaging device in which a voltage pulse is applied to a first polarity semiconductor, a pulse driving unit that outputs a driving pulse of the solid-state imaging device, a pulse driving unit, and a solid state And a protection unit arranged between the imaging device.
- the protection unit includes a capacitor connected between the output terminal of the pulse driving unit and the voltage terminal of the solid-state imaging device, a diode connected between the potential point and the voltage terminal, and between the voltage terminal and the potential point. Having a resistance element connected to. The anode end of the diode is connected to a potential point to which the potential of the voltage terminal is applied.
- a protection device for a solid-state imaging device is a protection device that protects a solid-state imaging device in which a voltage pulse is applied to a first polarity semiconductor, and outputs a driving pulse of the solid-state imaging device Between the pulse driving unit and the solid-state imaging device.
- a capacitor connected between the output terminal of the pulse driving unit and the voltage terminal of the solid-state imaging device, a diode connected between the potential point and the voltage terminal, and the voltage terminal and the potential point It has a resistance element connected between them. The anode end of the diode is connected to a potential point to which the potential of the voltage terminal is applied.
- the potential at the potential point is started before the power supply is started.
- the respective technologies and techniques described in the dependent claims of the imaging device according to the first aspect of the present disclosure can be similarly applied, and the configuration to which the techniques and methods are applied Defines a further advantageous embodiment of the protective device according to the second aspect.
- the protection unit and the protection device are configured to include a clamp circuit including a capacitor, a diode, and a resistance element.
- the capacitor performs a direct current cut function between the pulse driving unit and the solid-state imaging device.
- the diode has a clamping function.
- the resistance element performs a discharging function.
- the technology disclosed in this specification breaks a solid-state imaging device with a simple (three elements) clamp circuit composed of a DC cut capacitor, a clamp diode, and a discharge resistance element. ⁇ Use as a functional part to protect against deterioration.
- the diode by connecting the anode end of the diode to a potential point to which the potential of the voltage terminal is applied, when the AC component of the drive pulse (for example, electronic shutter drive pulse) is input to the voltage terminal of the solid-state imaging device, the diode Is always reverse biased and off. For this reason, the diode is normally off and power is not consumed, and a special and expensive diode is unnecessary, so that restrictions on component selection can be relaxed.
- the potential of the voltage terminal is held at the clamp potential by the diode. As a result, the solid-state imaging device can be protected from damage and deterioration.
- the imaging device and the protection device for a solid-state imaging device it is possible to provide a protection technology for a solid-state imaging device that can reduce the number of elements and can ease restrictions on component selection. Can do.
- FIG. 1 is a diagram (circuit configuration diagram) illustrating an imaging device and a protection device of Reference Configuration 1.
- FIG. 2 is a diagram (circuit configuration diagram) illustrating an imaging device and a protection device having a reference configuration.
- FIG. 3 is a diagram for explaining a startup sequence at the time of starting the first potential (positive power source) and the second potential (negative power source) required for the configuration shown in FIG.
- FIG. 4 is a diagram (circuit configuration diagram) for explaining the imaging device and the protection device of Reference Configuration 3.
- FIG. 5 is a diagram (circuit configuration diagram) for explaining the imaging device and the protection device of Reference Configuration 4.
- FIG. 6 is a diagram (circuit configuration diagram) for explaining the basic principle of element protection of the imaging device and the protection device of the present embodiment.
- FIG. 1 is a diagram (circuit configuration diagram) illustrating an imaging device and a protection device of Reference Configuration 1.
- FIG. 2 is a diagram (circuit configuration diagram) illustrating an imaging device and a protection device having
- FIG. 7 is a diagram for explaining the start-up sequence when starting the first potential (positive power source) and the second potential (negative power source) required for the configuration shown in FIG.
- FIG. 8 is a diagram (circuit configuration diagram) illustrating the imaging device and the protection device according to the first embodiment.
- FIG. 9 is a diagram (circuit configuration diagram) illustrating the imaging device and the protection device according to the second embodiment.
- FIG. 10 is a diagram (circuit configuration diagram) illustrating the imaging device and the protection device according to the third embodiment.
- FIG. 11 is a diagram (circuit configuration diagram) illustrating an imaging device and a protection device according to a modification example of the first to third embodiments.
- Example 1 Using a horizontal driver power source, the substrate voltage control circuit is in the solid-state imaging device
- Example 2 Using a horizontal driver power source, the substrate voltage control circuit is in the driver
- Example 3 For horizontal driver Power supply is used, substrate voltage control circuit is externally arranged. Modification: Power supply for CCD output circuit is used, substrate voltage control circuit is in solid-state imaging device.
- Example 4 Power supply for other functional units is used.
- the protection device is interposed between the solid-state imaging device and the pulse driving unit (for example, a shutter drive pulse wiring system).
- the pulse driving unit for example, a shutter drive pulse wiring system.
- the solid-state imaging device a device in which a voltage pulse is applied to a first polarity semiconductor is used. For example, by applying a voltage pulse to the first polarity semiconductor substrate as a shutter drive pulse, unnecessary charges accumulated in the charge accumulating portion can be swept out to the first polarity semiconductor substrate in accordance with the applied voltage.
- a solid-state imaging device configured as described above is used.
- the pulse driving unit outputs a driving pulse of the solid-state imaging device.
- a protection device disposed between the pulse driving unit and the solid-state imaging device has a function of protecting the solid-state imaging device from damage and deterioration.
- the pulse driving unit outputs each driving pulse of the vertical transfer system and the horizontal transfer system.
- attention can be paid to a shutter drive pulse.
- a solid-state imaging device is damaged or deteriorated by using a simple clamp circuit (three elements) consisting of a DC-cut capacitor, a clamp diode, and a discharge resistive element. It is used as a functional part that protects against The anode end of the diode is connected to a potential point to which the potential of the voltage terminal is applied (specifically, a potential point to which a potential corresponding to the rated voltage of the voltage terminal is applied).
- a potential point to which the potential of the voltage terminal is applied specifically, a potential point to which a potential corresponding to the rated voltage of the voltage terminal is applied.
- the diode Due to the connection to the potential point at the anode end, during normal operation, the diode is always reverse biased so it is turned off, no power is consumed, no special and expensive diode is required, and there are no restrictions on component selection. Things can be used.
- the voltage terminal potential is held at the clamp potential by the diode, so that the solid-state imaging device may be damaged or deteriorated. Absent.
- a potential corresponding to the maximum rated voltage of the voltage terminal is applied to the potential point. If a potential corresponding to the maximum rated voltage, which is the most severe condition, is applied to the potential point rather than a general rated voltage, the solid-state imaging device can be reliably protected from damage and deterioration.
- the forward voltage drop of the diode in order to “correspond to the rated voltage of the voltage terminal” or “correspond to the maximum rated voltage of the voltage terminal”, it is preferable to consider the forward voltage drop of the diode. Specifically, it is preferable that a potential lower than the sum of the rated voltage of the voltage terminal or the maximum rated voltage and the forward drop voltage of the diode is applied to the potential point. This is to prevent the diode connected to the voltage terminal from being turned on during normal operation and to protect the solid-state imaging device from damage and deterioration when the power supply is started or shut off.
- a potential lower than the sum of the rated voltage or maximum rated voltage of the voltage terminal and the minimum value of the forward voltage drop of the diode is preferably applied to the potential point. In this way, it is possible to prevent the diode connected to the voltage terminal from being turned on during normal operation even if there are variations, etc., and to reliably prevent the influence on normal operation regardless of variations.
- the solid-state imaging device can be protected from damage and deterioration when the power is turned on or off.
- the activation (rise) or cutoff (fall) of the potential point and the vertical that outputs the driving pulse of the solid-state imaging device or the vertical transfer system are preferable. It is better to define the order of starting (rising) and shutting off (falling) the power supply to the pulse drive unit.
- the pulse drive unit includes a vertical pulse drive unit that outputs a vertical transfer system drive pulse and a horizontal pulse drive unit that outputs a horizontal transfer system drive pulse
- the vertical pulse drive unit and the solid-state imaging device When the power source is activated, it is preferable that the potential at the potential point is activated before the power source is activated.
- a second potential which is a potential corresponding to the first polarity and which is opposite to the first direction with respect to the reference potential and the first potential in the first direction with respect to the reference potential. The one that outputs the second potential in the direction is used.
- the pulse drive unit When the pulse drive unit has a vertical pulse drive unit that outputs a drive pulse of a vertical transfer system and a horizontal pulse drive unit that outputs a drive pulse of a horizontal transfer system, it is for a vertical pulse drive unit and for a solid-state imaging device
- a potential corresponding to the first polarity, the first potential in the first direction with respect to the reference potential, and the second potential in the second direction opposite to the first direction with respect to the reference potential Use what you want to output.
- the second potential may be activated after the first potential is activated.
- the power to the solid-state imaging device when the power to the solid-state imaging device is shut off, it is preferable to shut off the power in the reverse order from when the power is activated. Specifically, when the power to the solid-state imaging device is cut off, it is preferable to cut off the potential point after the power is turned off. Further, as a power source for the vertical pulse driving unit and the solid-state imaging device, the potential corresponding to the first polarity is the first potential in the first direction with respect to the reference potential and the first direction with respect to the reference potential. The one that outputs the second potential in the second direction opposite to the above is used. At this time, when the power is shut off, it is preferable to shut off the first potential after shutting off the second potential.
- the pulse drive unit has a vertical pulse drive unit that outputs a vertical transfer system drive pulse and a horizontal pulse drive unit that outputs a horizontal transfer system drive pulse
- the vertical pulse drive unit and the solid-state imaging device When the power is shut off, it is preferable to shut off in the reverse order to that at the time of power activation. Specifically, when the power to the vertical pulse driving unit and the solid-state imaging device is shut off, it is preferable to shut off the potential point after the power is shut off.
- the potential corresponding to the first polarity is the first potential in the first direction with respect to the reference potential and the first direction with respect to the reference potential. The one that outputs the second potential in the second direction opposite to the above is used. At this time, when the power is shut off, it is preferable to shut off the first potential after shutting off the second potential.
- potential point connection destinations include the following power sources.
- a predetermined potential point may be connected to a power source for a horizontal pulse driving unit or a power source for an output unit that outputs an imaging signal of a solid-state imaging device.
- a power source for a horizontal pulse driving unit or a solid-state imaging device disposed near the protection device is used.
- the potential point may be connected to a power source for a functional unit other than the solid-state imaging device and the pulse driving unit.
- a power source for a functional unit other than the solid-state imaging device and the pulse driving unit In this case, the range of selection of the voltage value, the startup order, or the cutoff order is expanded. Also in this case, each of these power supplies may be arbitrarily selectable. Although wiring problems may occur, an optimum power source can be selected according to the actual situation and used as a potential point power source.
- a substrate voltage control circuit for applying a predetermined potential to the voltage terminal is preferably provided. If necessary, a predetermined potential may be applied to the voltage terminal via an output circuit using a diode or an emitter (or source) follower circuit.
- the emitter follower circuit and the source follower circuit are used when high input impedance and low output impedance are desired.
- the output circuit can be regarded as a (broadly defined) substrate voltage control circuit. That is, an emitter follower circuit or a source follower circuit is used when it is desired to increase the input impedance connected to the substrate potential control circuit and decrease the output impedance, or in any of these cases.
- the format of the output circuit depends on the configuration of the substrate potential control circuit and is not determined solely by the output circuit.
- the location of the substrate voltage control circuit (or the output circuit) may be in the solid-state imaging device, in the pulse driving unit, or outside the solid-state imaging device and the pulse driving unit. There are fewer peripheral members in the solid-state imaging device and the pulse driving unit, and the scale can be reduced.
- a capacitor connected in parallel with the resistance element may be provided in the protection unit.
- a semiconductor layer having a second polarity (for example, p-type) opposite to the first polarity formed on the main surface of a semiconductor substrate (first conductivity type region) having a first polarity (for example, n-type) ( The p layer, the second conductivity type region) is grounded, and a pulse of a predetermined voltage is applied as an electronic shutter pulse to the semiconductor substrate of the first polarity.
- the one having a configuration in which electric charges are swept out to the first polarity semiconductor substrate is used. Typically, this corresponds to a CCD, and the following description will be made assuming that a CCD is used.
- FIG. 1 is a diagram (circuit configuration diagram) illustrating an imaging device 1W and a protection device 400W of Reference Configuration 1.
- the imaging device 1W includes the solid-state imaging device 10, a vertical driver 42V, a driving power source 46 (local power source), and a protection device 400W (protection unit).
- a first potential V H positive power supply, for example, about 13 to 15 V
- the second potential V L negative power supply, for example, about ⁇ 6.5 to ⁇ 8 V
- the first potential V H is used as a positive power supply in accordance with the n-type substrate of the solid-state imaging device 10.
- the vertical driver 42V is supplied with vertical transfer clock V1 to vertical transfer clock Vv and an electronic shutter pulse SHT for the electronic shutter function as drive pulses for the vertical transfer system from a timing signal generator (not shown). However, a drive pulse for the horizontal transfer system is also supplied.
- the vertical driver 42V converts each pulse signal to a required level and supplies it to the solid-state imaging device 10 as drive pulses (vertical drive pulse ⁇ V_1 to vertical drive pulse ⁇ V_v, electronic shutter drive pulse ⁇ SHT, etc.).
- the electronic shutter drive pulse ⁇ SHT is output from the shutter terminal SUB of the vertical driver 42V and supplied to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10 via the protection device 400W.
- the solid-state imaging device 10 is mounted with a substrate voltage control circuit 402 and an output circuit 403 composed of a diode, a transistor, and the like, and a constant voltage (positive voltage) is applied through the output circuit 403, for example.
- the figure shows an emitter follower circuit using a bipolar transistor 404 as the output circuit 403.
- a source follower circuit using a MOSFET Metal-Oxide-Semiconductor Field-Effect Transistor
- the bipolar transistor 404 is always on in the forward direction between the base and the emitter, and supplies a constant voltage from the substrate voltage control circuit 402 to the substrate voltage terminal ⁇ SUB.
- the bipolar transistor 404 when the bipolar transistor 404 is used, there is a voltage drop corresponding to the base-emitter voltage Vbe.
- the protection device 400W includes a first clamp circuit 410W (pre-clamp circuit) configured by a capacitor 412, a diode 414, and a resistance element 416, and a second clamp configured by a capacitor 422, a diode 424, and a resistance element 426.
- Circuit 420W main clamp circuit.
- One end of the capacitor 412 is connected to the shutter terminal SUB, and the other end is connected to a connection point (denoted as a node ND410) between the cathode end of the diode 414, one end of the resistance element 416, and one end of the capacitor 422.
- the other end of the capacitor 422 is connected to the cathode end of the diode 424, one end of the resistance element 426, and the substrate voltage terminal ⁇ SUB.
- the anode end of the diode 414 and the resistance element 416, and the anode end of the diode 424 and the other end of the resistance element 426 are connected to a reference potential V M (ground in this example).
- the diode 424 when the absolute value of the forward drop voltage (specifically, the maximum value) of the diode 424 is VF, and the absolute value of the lower limit of the absolute maximum rating of the potential of the substrate voltage terminal ⁇ SUB is VL min , VF ⁇ VL A diode that satisfies min ( ⁇ VF> ⁇ VL min ), such as a Schottky diode, is used.
- the reverse blocking voltage of the diode 424 is set to Vr, the amplitude of the electronic shutter drive pulse ⁇ SHT is set to Ves, and the maximum value when the substrate voltage terminal ⁇ SUB is steady (when the electronic shutter is not applied) If V max , it is necessary to select a diode that satisfies Vr> Ves + V max . That is, during the electronic shutter operation, the diode 424 for a reverse voltage of up Ves + V max is applied, the reverse blocking voltage Vr of the diode 424 must be greater than that voltage Ves + V max.
- the terminal potential of the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10 is rated according to specifications.
- the terminal potential may be defined by the absolute maximum rating.
- Negative voltage may be applied. That is, when the second potential V L is raised before the first potential V H, a negative voltage is generated from the shutter terminal SUB of the vertical driver 42V, and this negative voltage is increased until the first potential V H rises. 10 substrate voltage terminals ⁇ SUB. For this reason, the potential of the substrate voltage terminal ⁇ SUB falls below the rated voltage.
- a negative voltage that is lower than the rated value from the shutter terminal SUB when the power is turned on by the two-stage first clamp circuit 410W and the second clamp circuit 420W. Can be prevented from being applied to the substrate voltage terminal ⁇ SUB.
- the drive power supply 46 is activated, the second potential V L is activated first, and then the first potential V H is activated. First, a negative voltage is output from the 42V shutter terminal SUB.
- the node ND410 and the reference potential V M and the diode 414 connected between the can because it is forward biased by the negative voltage, the diode 414 is turned on, the potential of the node ND410 forward of the diode 414 It becomes lower than the reference potential V M by voltage drop (VF). Then, the potential change at this time is transmitted to the substrate voltage terminal ⁇ SUB via the capacitor 422. At this time, since the first potential V H has not been applied yet, a negative voltage is applied to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10.
- diode 424 connected between the substrate voltage terminal ⁇ SUB and the reference potential V M, since forward biased by the negative voltage, the diode 424 is turned on, the potential of the substrate voltage terminal ⁇ SUB the diode 424 It becomes lower than the reference potential V M by the forward voltage drop (VF) of. Since the forward drop voltage VF of the diode 424 satisfies VF ⁇ VL min ( ⁇ VF> ⁇ VL min ), a large negative voltage lower than the lower limit voltage ⁇ VL min is applied to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10. Is prevented. The forward voltage drop of the diode 424 can prevent the lowering of the substrate voltage terminal ⁇ SUB from exceeding the lower limit.
- the diode 424 prevents the substrate voltage terminal ⁇ SUB from being applied with a large negative voltage lower than the lower limit voltage ⁇ VL min .
- the diode 414 and the diode 424 are normally turned off by setting the connection destination of the anode ends of the diode 414 and the diode 424 to the reference potential V M. I don't get up.
- a second clamp circuit 420W is provided.
- the diode 424 satisfies a special and expensive condition that satisfies VF ⁇ VL min ( ⁇ VF> ⁇ VL min ). There is a difficulty in choosing a diode.
- FIG. 2 is a diagram showing a circuit configuration
- FIG. 3 is a diagram for explaining a start-up sequence at the time of power activation of the first potential V H and the second potential V L required for the configuration. .
- the protection device 400X of the imaging device 1X is different from the protection device 400W in that the first clamp circuit 410X sets the connection destination of the anode end of the diode 414 to the first potential V H and removes the diode 424 to remove the second clamp circuit.
- the feature is that 420W is changed to a simple coupling circuit 430X (comprising a capacitor 432 and a resistor 436). Since the clamp circuit is only the first clamp circuit 410X, it will be referred to as a clamp circuit 410X below. In such a protection device 400X, since the diode 424 is not used, the number of parts is reduced.
- the capacitance value (capacitance, capacitance) of the capacitor 412 is, for example, 1 microfarad ( ⁇ F), and the resistance value of the resistance element 416 is, for example, 100 kilohms (k ⁇ ).
- the capacitance value of the capacitor 422 is, for example, 0.047 microfarad ( ⁇ F), and the resistance value of the resistance element 426 is, for example, 1 megaohm (M ⁇ ).
- Capacitor 412 must select a relatively large component based on its capacitance value, and capacitor 422 must also select a relatively large component based on its capacitance value. For example, it is difficult to select a so-called 0603 size or smaller ultra-small ceramic capacitor, and a film capacitor or a so-called 1005 size or smaller ceramic capacitor must be selected.
- an electronic shutter drive pulse ⁇ SHT (sweep pulse) is applied from the shutter terminal SUB of the vertical driver 42V to the substrate voltage terminal ⁇ SUB via the capacitor 412 and the capacitor 432.
- the diode 414 and the resistance element 416 between the capacitor 412 and the capacitor 432 protect against damage or deterioration due to a negative voltage applied to the n-type substrate of the solid-state imaging device 10. Since the DC voltage in the clamp circuit 410X is different from the shutter terminal SUB of the vertical driver 42V and the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10, two capacitors, a capacitor 412 and a capacitor 432, are provided to remove the DC component.
- the resistor 436 is a resistor for clamping the output of the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10.
- the output of the shutter terminal SUB (electronic shutter drive pulse ⁇ SHT) is input to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10 after being clamped at the first potential V H. Is done. Therefore, the n-type substrate can be protected from a negative voltage when the power is turned on.
- the first potential V H rises as shown in FIG. 3 in the order in which the first potential V H and the second potential V L are activated. It is required that the second potential V L rises later. For example, in FIG.
- the time is defined by the time at the 20 percent (%) point, the period until the first potential V H rises to the 20 percent (%) point is t1, and the second potential V L is 20 percent ( %)
- t2 is the period until the point rises, t2 ⁇ t1 must be satisfied.
- the protective device 400X of the reference configuration 2 can protect the n-type substrate from a negative voltage when the power is turned on, while 1) the problem of the number of parts, 2) the problem of the component size, and 3) the power consumption (for example, 1.6). 4) Problem of diode selection, 5) Problem of transition (modulation) time.
- 1) is improved compared to the protection device 400W, the coupling circuit 430 alone is not sufficient, and in order to realize the protection function, three first clamp circuits 410 as external components are provided. The problem is that the number of capacitors 412, diodes 414, and resistance elements 416 increases. 2) is a problem that the component size becomes large.
- the input voltage is divided by the capacitor 412 and the capacitor 432 and the substrate capacitance C ccd of the solid-state imaging device 10, and the input pulse amplitude is attenuated.
- the capacitors 412 and 432 need to have large capacitance values that do not attenuate the minimum pulse amplitude described in the specification of the solid-state imaging device 10.
- These parts also require, for example, a high breakdown voltage (for example, a breakdown voltage of 25 V or more).
- an electronic shutter drive pulse ⁇ SHT having a large amplitude (for example, about 20 V) is applied to the capacitor 412 and the capacitor 432.
- the capacitance values of the capacitor 412 and the capacitor 432 required for the protection device 400X require not only a high capacity but also a high breakdown voltage, and there is a problem that the component size increases.
- 3) is a problem caused by the constant need for current. This is because the clamp circuit 410X clamps the diode 414 with forward bias.
- 4) is a problem related to the selection of the diode 414. That is, in the protection device 400X, there is a problem that a reverse recovery time must be selected in order to apply a reverse bias AC signal to the forward bias diode 414. Although it may not be special compared to the diode 424 in the protection device 400W, a special and expensive diode compared to the diode 414 must be selected.
- the DC removal is performed twice. This is due to the problem that the transition time for the substrate voltage control of the solid-state imaging device 10 becomes relatively long.
- the transition time is proportional to the product (time constant) of the capacitance value C 412 of the capacitor 412 and the resistance value R 416 of the resistance element 416.
- the time constant for example, the capacitance value C 412
- the transition transition time becomes longer than that in the case of one time. End up.
- the transition time required for substrate voltage control of the solid-state imaging device 10 takes about 25 milliseconds.
- FIG. 4 is a diagram (circuit configuration diagram) for explaining the imaging device 1Y and the protection device 400Y of Reference Configuration 3.
- the image pickup apparatus 1Y is modified so that the substrate voltage control circuit 402 is mounted not in the solid-state image pickup apparatus 10 but in the vertical driver 42V, and a diode 406 is used as the output circuit 403 in place of the transistor 404 and the outside of the driver 42 is changed. It is characterized in that it is deformed to be disposed in Others are the same as the reference structure 2.
- the protection device 400Y of the reference configuration 3 is actually the same as the protection device 400X of the reference configuration 2, and has the same problem as the protection device 400X.
- the diode 406 is always turned on in the forward direction during normal operation, and supplies a constant voltage from the substrate voltage control circuit 402 to the substrate voltage terminal ⁇ SUB.
- the diode 406 when used as the output circuit 403, there is a voltage drop corresponding to the forward drop voltage.
- the circuit configuration is such that the vertical driver 42V and the diode 406 are present outside the solid-state imaging device 10, and therefore between the vertical driver 42V and the solid-state imaging device 10. As a whole, the increase in the number of parts becomes a problem.
- FIG. 5 is a diagram (circuit configuration diagram) for explaining the imaging device 1Z and the protection device 400Z of Reference Configuration 4.
- the reference configuration 4 is a mode in which the substrate voltage control circuit 402 is further modified with respect to the reference configuration 3 so that the substrate voltage control circuit 402 is arranged outside the solid-state imaging device 10 and the vertical driver 42V without being mounted. Others are the same as in Reference Configuration 3.
- the protection device 400Z of the reference configuration 4 is actually the same as the protection device 400X of the reference configuration 2, and has the same problems as the protection device 400X.
- the substrate voltage control circuit 402 is in a state in which it exists outside the vertical driver 42V and the solid-state imaging device 10 in terms of the circuit configuration.
- the number of parts and the circuit scale corresponding to the substrate voltage control circuit 402 are problematic.
- FIG. 6 shows a circuit configuration diagram of the imaging device 1 and the protection device 400 of the present embodiment
- FIG. 7 shows a first potential V H , a second potential V L, and a third potential required for the configuration. It is a diagram for explaining a fall point sequence during start-up sequence and power-off of the power supply startup V 3.
- the voltage difference between the input and output of the output circuit 403 (the difference between the potential of the output terminal of the substrate voltage control circuit 402 and the potential of the substrate voltage terminal ⁇ SUB) is assumed to be ⁇ V403.
- the output circuit 403 can be an emitter follower circuit using a bipolar transistor 404, a circuit using a diode 406, or a source follower circuit using a MOSFET such as a MOS type. Since the substrate voltage must be stable, it is usual to pass through an output circuit of an emitter follower circuit or a source follower circuit that performs impedance conversion on the output of the substrate control circuit 402.
- the diode 406 can be used when the output impedance of the substrate control circuit is sufficiently low.
- the voltage difference ⁇ V403 when the bipolar transistor 404 is used is the base-emitter voltage Vbe of the bipolar transistor 404, and the voltage difference ⁇ V403 when the diode 406 is used is the forward drop voltage of the diode 406.
- the voltage difference ⁇ V403 is a voltage difference by the source follower circuit.
- the clamp circuit 410 (corresponding to the first clamp circuit 410X) uses the connection destination of the anode end of the diode 414 as a power source for the third potential V 3 with respect to the protection device 400W. It is characterized in that the second clamp circuit 420W is removed.
- the clamp circuit has a single-stage configuration, and the coupling circuit 430 does not exist.
- the diode 414 may have a configuration in which a transistor is diode-connected. In such a protection device 400, since the second clamp circuit 420 and the coupling circuit 430 are not used, the number of parts is reduced.
- the capacitor 412 functions as a coupling circuit 430 for absorbing the voltage difference between the shutter terminal SUB and the substrate voltage terminal ⁇ SUB (removing the DC component).
- the capacitance value of the capacitor 412 is, for example, 0.01 microfarad ( ⁇ F)
- the resistance value of the resistance element 416 is, for example, 1 megaohm (M ⁇ ).
- the diode 414 and the resistance element 416 are explicitly arranged outside the solid-state imaging device 10, a configuration in which these are arranged in the solid-state imaging device 10 may be used.
- the “diode connected between the potential point (potential point of the third potential V3) and the voltage terminal (for example, the substrate voltage terminal ⁇ SUB)” is explicitly shown outside the solid-state imaging device 10.
- the “resistive element connected between the voltage terminal (for example, the substrate voltage terminal ⁇ SUB) and the potential point (for example, the reference potential VM)” is a resistive element explicitly shown outside the solid-state imaging device 10. Not only 416 but also a resistive element arranged in the solid-state imaging device 10 is included. Compared to any of Reference Configurations 1 to 4 described above, the capacitance value of capacitor 412 may be small.
- the resistance element 416 functions as a discharge resistance.
- a capacitor 418 (capacitance value is, for example, about 1000 to 4700 picofarad (pF)) may be provided in parallel with the resistance element 416, as indicated by a broken line in the drawing.
- the capacitor 418 is provided as a so-called decoupling capacitor, and is hardly affected by, for example, a vertical transfer clock or a horizontal transfer clock.
- a decoupling capacitor is required when the capacitive coupling between the transfer clock and the substrate voltage terminal ⁇ SUB in the image pickup apparatus is large or when the clock rises or falls sharply.
- the third potential V 3 is a potential between the reference potential V M and the first potential V H and is set to a predetermined potential corresponding to the maximum rated voltage of the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10. To do. Specifically, the following conditions shall be satisfied.
- the absolute value of the forward drop voltage of the diode 414 is VF
- “substrate voltage control circuit 402 + output When VL is the minimum voltage (preferably this voltage should be the minimum value including variation) output from circuit 403 to substrate voltage terminal ⁇ SUB, the lower limit is “V 3 ⁇ VF> ⁇ VL
- the third potential V 3 is selected so that the upper limit satisfies “V 3 ⁇ VF ⁇ minimum value of the substrate voltage terminal ⁇ SUB” (for example, a 1.8 V system or a 3 V system is used).
- This condition is referred to as a rated voltage condition of the third potential V 3 .
- This voltage condition is preferably satisfied even when variations are considered.
- the maximum value of the third potential V3 is V3max
- the lower limit of the absolute value of the forward drop voltage of the diode 414 (the forward drop voltage of the diode 414).
- VF min and the lower limit of the absolute value of the absolute maximum rating of the potential of the substrate voltage terminal ⁇ SUB minimum voltage of the substrate voltage terminal ⁇ SUB, that is, the minimum allowable voltage
- VL min the lower limit
- the lower limit is “V 3max ⁇ It is preferable that “VF min > ⁇ VL min ” is satisfied.
- This condition is referred to as the maximum allowable condition of the third potential V 3 .
- the maximum permissible condition is defined by taking a minimum value for both the forward voltage drop of the diode 414 and the rated voltage (allowable voltage) of the substrate voltage terminal ⁇ SUB, but defining either one as a rated value. Also good. In this case, compared with the maximum allowable condition, there is a possibility of affecting the normal operation depending on the variation. This is because the diode 414 connected to the substrate voltage terminal ⁇ SUB may be turned on during normal operation. On the other hand, the maximum allowable condition described above represents a condition for preventing the diode 414 from turning on in the forward direction, and the diode 424 connected to the substrate voltage terminal ⁇ SUB is turned on during normal operation even if there are variations. Can be avoided. As a result, the influence on the normal operation can be surely prevented regardless of variations and the like, and the solid-state imaging device 10 can be reliably protected from damage or deterioration when the power is turned on or off.
- the output of the shutter terminal SUB (electronic shutter drive pulse ⁇ SHT) is input to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10 after being clamped at the third potential V 3. Is done. Therefore, the n-type substrate can be protected from a negative voltage when the power is turned on.
- the start-up sequence at the time of power activation of the first potential V H , the second potential V L, and the third potential V 3 is the state shown in FIG. It is preferable to satisfy. That is, it is preferable that the third potential V 3 rises (starts up) before the first potential V H and the second potential V L rise (starts up). This condition is referred to as a start condition of the third potential V3.
- the first potential V H and the second potential V L after the third potential V 3 rises are activated in the order of startup when the first potential V H rises as shown in FIG. It is preferable that the second potential V L rises (starts up) after (starts up). This means, for example, that it may be the same as the state shown in FIG.
- the order of lowering (shut-off) at the time of power-off of the first potential V H , the second potential V L and the third potential V 3 satisfies the state shown in FIG. That is, it is preferable that the third potential V 3 falls (cuts off) after the first potential V H or the second potential V L falls (cuts off). This condition is referred to as a stop condition of the third potential V 3 .
- the order of lowering the first potential V H and the second potential V L before the third potential V 3 falls (shuts down) when the power is shut off is, as shown in FIG. It is preferable that the first potential V H falls (cuts off) after L falls (cuts off). This means, for example, that the power supply may fall in the reverse order to that shown in FIG. For example, as shown in FIG.
- the solid state imaging device 10 rises earlier when the power is turned on than the first potential V H (positive power source) and the second potential V L (negative power source).
- a power source that supplies the third potential V 3 that falls after the power source of the solid-state imaging device 10 falls is required.
- the third potential V 3 satisfies the maximum allowable condition (V 3max > ⁇ VL min + VF min ), and the power of the solid-state imaging device 10 and the vertical driver 42V (first potential V H , with rises before second potential V L) rises, it is assumed that at the time of power-off supplied from falling power after the fall of the power of the solid-state imaging device 10 and the vertical driver 42V.
- the drive power supply 46 raises the first potential V H and the second potential V L.
- these supplies depending on the startup timing and slew rate of the negative power supply for the positive power source and the second electric potential V L for the first potential V H, a negative voltage from the shutter terminal SUB of the vertical driver 42V
- the solid-state imaging device 10 may come out of the substrate voltage terminal ⁇ SUB.
- the protection device 400 is provided, and even when such a negative voltage is lost to the substrate voltage terminal ⁇ SUB, the diode 414 connected to the substrate voltage terminal ⁇ SUB responds to the power supply. Since the protection function at the time of activation works, it is possible to prevent the substrate voltage terminal ⁇ SUB from becoming a negative voltage.
- the protection device 400 does not require a steady-state current, so that the power consumption of the protection device 400 is substantially reduced (except for the amount that the protection function works). It can be 0 milliwatts.
- the capacitor 412 is used as a member having a DC component removal function provided between the vertical driver 42V and the solid-state imaging device 10. Since the DC removal (DC cut) only needs to be performed once, the capacitance value of the capacitor 412 can be made smaller than those of the reference configurations 1 to 4, and for example, a so-called 0603 size or smaller ultra-small ceramic capacitor can be used. You can also choose.
- the transition time required for substrate voltage control of the solid-state imaging device 10 is also shortened. This is because the transition time in the case where DC removal is performed once (using only the capacitor 412) is proportional to the product of the capacitance value C 412 of the capacitor 412 and the resistance value R 416 of the resistance element 416.
- the transition time for the substrate voltage control of the solid-state imaging device 10 can be about 2 milliseconds.
- the shortening of the transition time is described numerically in comparison with the reference configuration 2 as follows.
- T1 time constant
- T3 time constant
- the voltage applied to both ends of the capacitor 412 can also be suppressed.
- the capacitor 412 is connected to the clamp potential (for example, 12.6 V) of the diode 414 in the reference configurations 2 to 4, whereas the substrate of the solid-state imaging device 10 is used in the protection device 400 of the present embodiment.
- the voltage of the substrate voltage terminal ⁇ SUB is approximately 5V to 11V, although it varies depending on the solid-state imaging device 10 and its operation mode. Therefore, the inter-terminal voltage applied to the capacitor 412 can be suppressed more than in the reference configurations 2 to 4.
- the shutter of the vertical driver 42V depends on the fall timing and the slew rate, as in the case of the rise.
- a negative voltage may be discharged from the terminal SUB to the substrate voltage terminal ⁇ SUB of the solid-state imaging device 10.
- the protection device 400 is provided, and even when such a negative voltage is lost to the substrate voltage terminal ⁇ SUB, the diode 414 connected to the substrate voltage terminal ⁇ SUB responds to the power supply. Since the protection function at the time of interruption works, it is possible to prevent the substrate voltage terminal ⁇ SUB from becoming a negative voltage.
- the third potential V 3 is lowered.
- the diode 414 is turned off and the protection function is stopped.
- an abnormal voltage (specifically, on the semiconductor substrate of the solid-state imaging device 10 such as a CCD when the power is turned on or off with a simple configuration with a small number of components. can prevent the second direction with respect to the reference potential V M voltage (minus direction)) is applied. Since the protection device 400 according to the present embodiment uses only the capacitor 412 as a member for removing direct current between the vertical driver 42V and the solid-state imaging device 10, the removal of the direct current component is sufficient.
- the capacitance value of the capacitor 412 can be reduced, a smaller part (for example, an ultra-small ceramic capacitor of 0603 size) can be selected, and further, the transition time required for the substrate voltage control of the solid-state imaging device 10 is shortened. it can. Furthermore, according to the protection device 400 of the present embodiment, since the voltage across the capacitor 412 can be suppressed, it is not easily affected by the DC bias dependency of the capacitor 412, and a steady current is not required. Does not require a diode.
- FIG. 8 is a diagram (circuit configuration diagram) illustrating the imaging device 1A and the protection device 400A according to the first embodiment.
- Example 1 (other embodiments described later as well) is characterized in that it utilizes the power being supplied to the horizontal driver 42H as a power source for the third potential V 3.
- the substrate voltage control circuit 402 and the output circuit 403 are provided in the solid-state imaging device 10.
- the substrate voltage control circuit 402 has a substrate voltage control circuit 402 inside the device.
- the image pickup apparatus 1A includes the solid-state image pickup apparatus 10, a timing signal generation unit 40, a driver 42 (pulse drive unit), a drive power supply 46, and a protection device 400A (the protection device 400 of the present embodiment described above). .
- the protection device 400 ⁇ / b> A is disposed between the driver 42 and the solid-state imaging device 10.
- an interline CCD solid-state imaging device in which vertical charge transfer units are arranged between sensor units (vertical direction) is used as a v-phase (for example, 4 phase).
- the CCD type solid-state imaging device 10 includes a plurality of sensor units 11 (photosensitive units; photocells) each including a photodiode as an example of a light receiving element corresponding to pixels (unit cells) on a semiconductor substrate. ) And imaging areas 14 (imaging sections) arranged in a two-dimensional matrix in the horizontal (row) direction.
- a vertical transfer unit 13 (also referred to as a vertical CCD, a V register unit, or a vertical charge transfer unit) provided with a plurality of vertical transfer electrodes corresponding to v-phase driving for each vertical column of the sensor unit 11 is provided. ) Are arranged. Each vertical transfer electrode is formed so that several (for example, two) vertical transfer electrodes correspond to one sensor unit 11, and v types of vertical drive pulses ⁇ V (supplied from the driver 42 based on the vertical transfer clock) ⁇ V_1 to ⁇ V_v) is configured to transfer and drive charges in the vertical direction.
- the charge transfer direction is a vertical (column) direction in the figure, and a vertical transfer unit 13 is provided in this direction, and a plurality of vertical transfer electrodes are arranged in a direction (horizontal direction, row direction) orthogonal to this direction.
- the main charge transfer direction (the direction from right to left in the drawing) is adjacent to the vertical transfer unit 13 in the last row, which is the transfer destination side end of the plurality of vertical transfer units 13.
- the horizontal transfer unit 15 is provided with a plurality of horizontal transfer registers 212 extending. In the illustrated example, the horizontal transfer register 212 is arranged up to an area exceeding the imaging area 14 (element part).
- the horizontal transfer unit 15 includes a horizontal transfer path 210 (also referred to as a horizontal CCD, an H register unit, or a horizontal charge transfer unit) in which a plurality of horizontal transfer registers 212 are arranged in the transfer direction.
- a surplus charge sweeping unit may be provided on the opposite side of the horizontal transfer path 210 from the vertical transfer unit 13 (imaging area 14).
- the horizontal transfer paths 210 are not limited to one line but may be provided for a plurality of lines. In this case, the surplus charge sweeping units are arranged to match the number of horizontal transfer paths 210.
- the horizontal transfer path 210 is transferred and driven by a horizontal drive pulse ⁇ H ( ⁇ H_1 to ⁇ H_h) based on, for example, an h-phase (for example, two-phase or four-phase) horizontal transfer clock, and transferred from a plurality of vertical transfer units 13.
- the amount of charge is sequentially transferred in the horizontal direction in the horizontal scanning period after the horizontal blanking period. For this reason, a plurality of (for example, two) horizontal transfer electrodes corresponding to the h-phase drive are provided.
- the horizontal transfer register 212 at the final stage, which is an end in the transfer direction, is referred to as a final horizontal transfer register 214 (LHreg).
- a unit 16 (CCD output circuit (output unit)) is provided.
- a dedicated power source is supplied from the drive power source 46 to the charge / electrical signal converter 16.
- a connection point of the charge / electrical signal conversion unit 16 to the final horizontal transfer register 214 is referred to as a charge input unit 17.
- the charge / electrical signal converter 16 only needs to be able to detect fluctuations in the electric signal in accordance with the amount of charge in the charge input unit 17, and can take various configurations.
- an amplifying circuit having a floating diffusion amplifier (FDA: FloatingmpDiffusion Amp) configuration in which a floating diffusion (Floating Diffusion: FD portion), which is a diffusion layer having a parasitic capacitance, is used for the charge input portion 17 (in this example, a charge storage portion).
- FDA floating diffusion amplifier
- FD portion floating diffusion
- a horizontal output gate 230 (HOG: Hreg Output Gate) is arranged on the charge / electrical signal conversion unit 16 side of the final stage horizontal transfer register 214, and a connection point between the charge / electrical signal conversion unit 16 and the horizontal output gate 230 is arranged. Is provided with a floating diffusion portion.
- the floating diffusion portion is connected to the gate of the transistor forming the charge / electrical signal conversion portion 16.
- the charge / electrical signal conversion unit 16 accumulates charges sequentially injected from the horizontal transfer unit 15 in a floating diffusion (not shown), converts the accumulated charges into a signal voltage, and, for example, via an output circuit having a source follower configuration (not shown). And output as an imaging signal Vo (CCD output signal).
- the source follower at the output stage of the charge / electrical signal converter 16 does not have sufficient driving capability. Therefore, the imaging signal Vo output from the charge / electrical signal conversion unit 16 is first input to the buffer unit 60 and the analog front end via the buffer unit 60 so that the CCD output signal amplified by the source follower does not deteriorate. It is sent to the signal processing unit of the AFE.
- the present invention is not limited to this, and various configurations can be adopted as long as the charge input unit 17 has a charge / electrical signal conversion function, such as a configuration using a floating gate.
- the timing signal generator 40 generates various pulse signals (binary of “L” level and “H” level) for driving the solid-state imaging device 10 and supplies them to the driver 42.
- the driver 42 supplies various drive clocks (drive pulses) supplied from the timing signal generator 40 to the solid-state imaging device 10 as drive pulses of a predetermined level.
- the timing signal generation unit 40 reads out the read pulse VRG for reading out the charges accumulated in the sensor unit 11 of the solid-state imaging device 10 based on the horizontal synchronization signal (HD) and the vertical synchronization signal (VD), and the read out charges.
- Vertical transfer system drive clocks such as vertical transfer clock V1 to vertical transfer clock Vv (v indicates the number of phases during driving; for example, V4 during four-phase driving) for driving the signals in the vertical direction and passing them to the horizontal transfer unit 15 Is generated.
- the solid-state imaging device 10 corresponds to an electronic shutter, and the timing signal generation unit 40 also supplies an electronic shutter pulse SHT to the vertical transfer system driver 42.
- the timing signal generation unit 40 further transfers the horizontal transfer clock H1 to the horizontal transfer clock Hh (h is a value at the time of driving) for transferring and driving the charge transferred from the vertical transfer unit 13 to the charge / electrical signal conversion unit 16 in the horizontal direction.
- the driver 42 converts various clock pulses supplied from the timing signal generation unit 40 into voltage signals (drive pulses) of a predetermined level, or converts them into other signals and supplies them to the solid-state imaging device 10.
- the driver 42 includes a level shift unit 42LS, a vertical driver 42V that drives the vertical transfer unit 13, a horizontal driver 42H that drives the horizontal transfer unit 15, and a horizontal output driver 42HRG that drives the horizontal output gate 230 (HOG) (horizontal reset).
- a horizontal final stage driver 42LH (LH driver) for driving the final stage horizontal transfer register 214 (LHreg).
- the horizontal driver 42H, the horizontal final stage driver 42LH, and the horizontal output driver 42HRG are all examples of a horizontal pulse driving unit that outputs a driving pulse of a horizontal transfer system.
- Various drive clocks are supplied from the timing signal generator 40 to the level shifter 42LS.
- the level shift unit 42LS converts the low level or high level of the drive clock into a required level and supplies it to the vertical driver 42V, the horizontal driver 42H, the horizontal output driver 42HRG, and the horizontal final stage driver 42LH.
- Each of the level shift unit 42LS, the vertical driver 42V, the horizontal driver 42H, the horizontal output driver 42HRG, and the horizontal final stage driver 42LH is supplied with power having a voltage value suitable for each.
- a first potential V H and the second electric potential V L is supplied to the solid-state imaging device 10 and the vertical driver 42V such as the power supply voltage, the horizontal driver supply voltage V HD horizontal driver 42H Is supplied as a power supply voltage.
- the connection destination of the anode end of the diode 414 of the protection device 400A is the power supply end of the horizontal driver 42H.
- the third potential V 3 coincides with the horizontal driver power supply potential V HD .
- VL min + VF min V L min + VF min
- the protective device 400A (particularly the diode 414) functions as a protective function at the time of power activation and a protective function at the time of power interruption. Even when the substrate voltage terminal ⁇ SUB is disconnected, the substrate voltage terminal ⁇ SUB can be prevented from becoming a negative voltage.
- FIG. 9 is a diagram (circuit configuration diagram) illustrating the imaging device 1B and the protection device 400B according to the second embodiment.
- the second embodiment is different from the first embodiment in that the substrate voltage control circuit 402 and the output circuit 403 are mounted in the driver 42 instead of the solid-state imaging device 10.
- 2 is an example of an external generation type in which a substrate voltage is supplied from a substrate voltage control circuit 402 provided outside the solid-state imaging device 10.
- the protection device 400B is the same as the protection device 400A.
- the connection destination of the anode end of the diode 414 of the protection device 400B is the power supply end of the horizontal driver 42H.
- the order of falling in time is the same as that in the first embodiment.
- the protection function at the time of power activation by the protection device 400B (particularly the diode 414) and the protection function at the time of power interruption work, so that a negative voltage is applied to the substrate voltage terminal ⁇ SUB at the time of power activation or power interruption. Even in the case of falling out, the substrate voltage terminal ⁇ SUB can be prevented from becoming a negative voltage.
- FIG. 10 is a diagram (circuit configuration diagram) illustrating the imaging device 1C and the protection device 400C according to the third embodiment.
- the third embodiment is different from the first embodiment in that the substrate voltage control circuit 402 and the output circuit 403 are arranged outside the solid-state imaging device 10 and the driver 42 instead of them.
- This is another example of an external generation type in which a substrate voltage is supplied from a substrate voltage control circuit 402 provided outside the solid-state imaging device 10.
- the protection device 400C is the same as the protection device 400A.
- the connection destination of the anode end of the diode 414 of the protection device 400C is the power supply end of the horizontal driver 42H.
- the order of falling in time is the same as that in the first embodiment.
- the power source for the horizontal driver 42H is used as the power source for the third potential V3 by connecting the anode end of the diode 414 of the protection device 400 to the power source end of the horizontal driver 42H.
- the power supply for the third potential V3 is not limited to the power supply for the horizontal driver 42H.
- a power supply for functional units other than the vertical driver 42V such as the level shift unit 42LS, the horizontal output driver 42HRG, or the horizontal final stage driver 42LH, which is also mounted in the driver 42, may be used.
- a power supply for functional units other than the vertical driver 42V such as the level shift unit 42LS, the horizontal output driver 42HRG, or the horizontal final stage driver 42LH, which is also mounted in the driver 42, may be used.
- a power source for the charge / electric signal converter 16 that functions as an output circuit of the solid-state imaging device 10 may be used.
- the driver 42 or the power supply for the solid-state imaging device 10 disposed in the vicinity of the protection device 400 is used, so that there is no inconvenience of wiring.
- FIG. 11 shows a modification to the configuration of the first embodiment, the same modification can be applied to the second and third embodiments. Moreover, you may comprise so that these each power supplies can be selected arbitrarily. In this case, an optimum power source can be selected according to the actual situation and used as the power source for the third potential V 3 . A configuration in which the power sources in the driver 42 are switched and used can be easily realized.
- the power source potential for each functional unit satisfies the rated voltage condition or the maximum allowable condition of the third potential V 3 as in the first embodiment.
- the order of falling in time can be the same as in the first embodiment.
- the fourth embodiment is different from the first to third embodiments in that each function unit of the driver 42 (excluding the vertical driver 42V) or the charge / electric signal conversion unit of the solid-state imaging device 10 is used as a power source for the third potential V 3 . 16 is characterized in that the power supplied to the functional units other than these is used instead of using the power supplied to 16.
- the imaging apparatus 1 when the imaging apparatus 1 is configured, the solid-state imaging apparatus 10, the analog front end AFE, the drive control unit, and other peripheral circuits may be accommodated in one package and provided as an imaging apparatus module.
- the analog front end AFE excluding the solid-state imaging device 10 from the imaging device module and the drive control unit are collectively referred to as a CCD camera front end (analog front end in a broad sense).
- the imaging device 1 may be entirely constituted by the imaging device module, an optical system (imaging lens as a main part), and a main unit.
- the main unit has a functional part that generates a video signal based on an imaging signal obtained by the imaging device module and outputs it to a monitor or stores an image in a predetermined storage medium.
- the following power sources for the third potential V 3 can be selection candidates.
- condition for the third potential V 3 described above rated voltage condition or maximum allowable condition, preferably start condition and stop condition also
- An example is given below.
- power sources used in the CCD camera front end are candidates, such as a timing pulse generation circuit, a CDS circuit (correlated double sampling), an OB (Optical Black) clamp circuit, an AD conversion circuit, a calibration circuit, and a DLL.
- a power supply used in a circuit, a PLL circuit, an input / output (IO, INPUT / OUTPUT) circuit, a high-speed interface circuit, a CMOS output circuit, an LVDS output circuit, or the like may be used.
- a power source used in a DSP, FPGA, CPU, memory (volatile memory, SDRAM, nonvolatile memory, flash memory) or the like can be used.
- the power source used by the interface unit is a candidate, for example, USB, HDMI, RGB output, video output, PCI Express (registered trademark), PCI, AGP, RS-232C, ISA, IDE, SATA, etc.
- An interface power supply may be used.
- a power source supplied from a battery such as a dry battery, a button battery, or a lithium ion battery may be used.
- a power supply used by the power supply IC is also a candidate, and for example, a power supply used in a DCDC converter or an ACDC converter can be used.
- a power source used by the display unit (display) is also a candidate, and for example, a power source used in a liquid crystal, an organic EL, a cathode ray tube, a touch panel, or the like can be used.
- the power source used by the oscillator and the oscillator, the power source for communication (whether it is wireless or wired), the power source for drivers used for strobe, LED, button operation, etc. are also used. obtain.
- the power source used by the data storage unit (storage) is also a candidate.
- the power source used in a hard disk device, SSD, flexible disk, CD (compact disk), DVD, Blu-ray, MO, HD-DVD, etc. can be used.
- a power source for lens control, a power source for various sensors such as a GPS, an acceleration sensor, or a temperature sensor can be used.
- [Appendix 1] A solid-state imaging device in which a voltage pulse is applied to a first polarity semiconductor; A pulse driving unit that outputs a driving pulse of the solid-state imaging device; A protection unit disposed between the pulse driving unit and the solid-state imaging device; And The protection unit includes a capacitor connected between the output terminal of the pulse driving unit and the voltage terminal of the solid-state imaging device, a diode connected between the potential point and the voltage terminal, and between the voltage terminal and the potential point.
- An imaging apparatus in which a potential at a potential point is activated before the power supply is activated when the power supply to the solid-state imaging apparatus is activated.
- Appendix 2 The imaging apparatus according to appendix 1, wherein a potential corresponding to the maximum rated voltage of the voltage terminal is applied to the potential point.
- Appendix 3 The imaging apparatus according to claim 1 or 2, wherein a potential lower than a sum of a rated voltage of the voltage terminal and a forward voltage drop of the diode is applied to the potential point.
- [Appendix 4] The imaging apparatus according to appendix 3, wherein a potential lower than a sum of a minimum allowable voltage of the voltage terminal and a forward voltage drop of the diode is applied to the potential point.
- [Appendix 5] The imaging apparatus according to any one of appendix 1 to appendix 4, wherein a potential lower than a sum of a rated voltage of the voltage terminal and a minimum value of a forward drop voltage of the diode is applied to the potential point.
- [Appendix 6] The imaging apparatus according to appendix 5, wherein a potential lower than a sum of a minimum allowable voltage of the voltage terminal and a minimum value of the forward voltage drop of the diode is applied to the potential point.
- the pulse drive unit has a vertical pulse drive unit that outputs a drive pulse of a vertical transfer system, and a horizontal pulse drive unit that outputs a drive pulse of a horizontal transfer system,
- the imaging apparatus according to any one of appendix 1 to appendix 6, wherein when the power to the vertical pulse driving unit and the solid-state imaging apparatus is activated, the potential at the potential point is activated before the activation of the power supply.
- Appendix 8 As a power source for the solid-state imaging device, a potential corresponding to the first polarity and having a first potential in the first direction with respect to the reference potential and a second direction opposite to the first direction with respect to the reference potential The one that outputs the second potential is used, 8.
- the pulse drive unit has a vertical pulse drive unit that outputs a drive pulse of a vertical transfer system, and a horizontal pulse drive unit that outputs a drive pulse of a horizontal transfer system, 11.
- the imaging device according to any one of supplementary notes 1 to 10, wherein the potential point is connected to a power supply for a horizontal pulse driving unit.
- the solid-state imaging device has an output unit that outputs an imaging signal, 11.
- [Appendix 15] A substrate voltage control circuit for applying a predetermined potential to the voltage terminal; 14.
- the imaging device according to any one of supplementary notes 1 to 13, wherein the substrate voltage control circuit is mounted in the pulse driving unit.
- the imaging device according to any one of supplementary notes 1 to 13, wherein the substrate voltage control circuit is disposed outside the solid-state imaging device and the pulse driving unit.
- the protection unit includes a capacitor connected in parallel with the resistance element.
- a protection device for protecting a solid-state imaging device in which a voltage pulse is applied to a first polarity semiconductor It is arranged between the pulse drive unit that outputs the drive pulse of the solid-state imaging device and the solid-state imaging device, A capacitor connected between the output terminal of the pulse driver and the voltage terminal of the solid-state imaging device, a diode connected between the potential point and the voltage terminal, and connected between the voltage terminal and the potential point Having a resistance element, The anode end of the diode is connected to a potential point to which the potential of the voltage terminal is applied, A protection device for a solid-state imaging device in which a potential at a potential point is activated before the power source is activated when the power source for the solid-state imaging device is activated.
- the pulse drive unit has a vertical pulse drive unit that outputs a drive pulse of a vertical transfer system, and a horizontal pulse drive unit that outputs a drive pulse of a horizontal transfer system, Item 19.
- SYMBOLS 1 ... Imaging device, 10 ... Solid-state imaging device, 11 ... Sensor part, 13 ... Vertical transfer part (vertical CCD), 14 ... Imaging area, 15 ... Horizontal transfer part (horizontal CCD), 16 ... Charge-electric signal conversion part, 40: Timing signal generation unit, 42: Driver, 42H: Horizontal driver, 42LH: Horizontal final stage driver, 42HRG: Horizontal output driver, 42V: Vertical driver, 46: Drive power supply, 60: Buffer unit, 210: Horizontal transfer path, 212 ... Horizontal transfer register, 214 ... Last stage horizontal transfer register, 230 ... Horizontal output gate, 400 ... Protection device (protection unit), 410 ... Clamp circuit, 412 ... Capacitor, 414 ... Diode, 416 ... Resistance element, 418 ... Capacitor
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Abstract
Description
1.全体概要
2.参考構成
3.素子保護の基本原理
4.具体的な適用例
実施例1:水平ドライバ用電源を利用、基板電圧制御回路は固体撮像装置内
実施例2:水平ドライバ用電源を利用、基板電圧制御回路はドライバ内
実施例3:水平ドライバ用電源を利用、基板電圧制御回路は外部配置
変形例 :CCD出力回路用電源を利用、基板電圧制御回路は固体撮像装置内
実施例4:他の機能部用電源を利用
先ず、基本的な事項について以下に説明する。本明細書で開示する撮像装置及び固体撮像装置の保護装置においては、固体撮像装置とパルス駆動部との間(例えば、シャッタドライブパルスの配線系統)に保護装置を介在させる。固体撮像装置としては、第1極性の半導体に電圧のパルスが印加されるものを使用する。例えば、第1極性の半導体基板に電圧のパルスがシャッタドライブパルスとして印加されることにより、印加された電圧に応じて、電荷蓄積部に蓄積された不要電荷を第1極性の半導体基板に掃出し可能に構成されている固体撮像装置を使用する。パルス駆動部は、固体撮像装置の駆動パルスを出力する。パルス駆動部と固体撮像装置との間(例えばシャッタドライブパルスの配線系統)に配置された保護装置は、固体撮像装置を破損・劣化から保護する機能を持つ。例えば、パルス駆動部は、垂直転送系や水平転送系の各駆動パルスを出力するが、一例として、シャッタドライブパルスに着目することができる。但し、これは一例に過ぎず、その他のドライブパルスに関しても、ドライブパルスの供給回路によっては、シャッタドライブパルスに関する保護手法を同様に適用できる。
次に、本明細書で開示する技術の理解を容易にするべく、幾つかの参考構成について説明する。尚、以下では、一例として、電子シャッタドライブパルスに関して説明するが、その他のドライブパルスに関しても、ドライブパルスの供給回路によっては、本明細書で開示する保護技術を同様に適用することができる。固体撮像装置としては、第1極性(例えばn型)の半導体基板(第1導電型領域)の主面に形成された第1極性とは反対の第2極性(例えばp型)の半導体層(p層、第2導電型領域)が接地され、第1極性の半導体基板に所定電圧のパルスが電子シャッタパルスとして印加されることにより、この印加電圧に応じて、電荷蓄積部に蓄積された不要電荷が第1極性の半導体基板に掃き出される構成を有するものを使用する。典型的にはCCDが該当し、以下では、CCDを用いるものとして説明する。
図1は、参考構成1の撮像装置1W及び保護装置400Wを説明する図(回路構成図)である。撮像装置1Wは、固体撮像装置10、垂直ドライバ42V、駆動電源46(ローカル電源)、及び、保護装置400W(保護部)を備える。駆動電源46からは、基準電位VM(接地電位)に対して第1の方向(プラス方向)の第1電位VH(正電源、例えば13~15V程度)と第2の方向(マイナス方向)の第2電位VL(負電源、例えば-6.5~-8V程度)とが電源電圧として固体撮像装置10や垂直ドライバ42V等に供給される。第1電位VHを正電源とするのは、固体撮像装置10の基板がn型であることに応じたものである。
図2~図3は、参考構成2の撮像装置1X及び保護装置400Xを説明する図である。ここで、図2は、回路構成を示す図であり、図3は、当該構成に要求される第1電位VHと第2電位VLの電源起動時の立上げ順序を説明する図である。
図4は、参考構成3の撮像装置1Y及び保護装置400Yを説明する図(回路構成図)である。撮像装置1Yは、基板電圧制御回路402を固体撮像装置10内ではなく垂直ドライバ42V内に実装するように変形し、又、出力回路403としてトランジスタ404に代えてダイオード406を使用しドライバ42の外部に配置するように変形した点に特徴を有する。その他は参考構成2と同様である。参考構成3の保護装置400Yは、実態としては、参考構成2の保護装置400Xと同じであり、保護装置400Xと同様の問題を有する。ダイオード406は、通常動作時は、常に順方向でオンしており、基板電圧制御回路402からの一定の電圧を基板電圧端子φSUBに供給する。因みに、出力回路403としてダイオード406を使用する場合、その順方向降下電圧分の電圧低下がある。尚、保護装置400Yそのものの問題点ではないが、回路構成上は、垂直ドライバ42V及び固体撮像装置10の外部にダイオード406が存在する状態となるため、垂直ドライバ42Vと固体撮像装置10との間の構成部材全体として見れば、部品点数の増加が問題となる。
図5は、参考構成4の撮像装置1Z及び保護装置400Zを説明する図(回路構成図)である。参考構成4は、参考構成3に対して更に、基板電圧制御回路402を固体撮像装置10及び垂直ドライバ42Vの何れにも実装せずにそれらの外部に配置するように変形した態様である。その他は参考構成3と同様である。参考構成4の保護装置400Zも、実態としては、参考構成2の保護装置400Xと同じであり、保護装置400Xと同様の問題を有する。参考構成4の場合、保護装置400Zそのものの問題点ではないが、回路構成上は、基板電圧制御回路402が垂直ドライバ42V及び固体撮像装置10の外部に存在する状態となるため、垂直ドライバ42Vと固体撮像装置10との間の構成部材全体として見れば、基板電圧制御回路402の分の部品点数や回路規模の増大が問題となる。
以上説明したように、参考構成1~参考構成4は、依然として、素子数や部品選定等の面で解決すべき点がある。そこで、本実施形態では、素子数をより低減でき、又、部品選定の制約を緩和することのできる新たな保護装置400を提案する。
図6~図7は、本実施形態の保護装置400の基本構成と、保護装置400における固体撮像装置10の基板電圧端子φSUBへの異常電圧の印加を防止する原理を説明する図である。ここで、図6は、本実施形態の撮像装置1及び保護装置400の回路構成図を示し、図7は、当該構成に要求される第1電位VHと第2電位VLと第3電位V3の電源起動時の立上げ順序及び電源遮断時の立下げ順序を説明する図である。
先ず、出力回路403の入出力間の電圧差(基板電圧制御回路402の出力端の電位と基板電圧端子φSUBの電位との差)をΔV403とする。出力回路403としては、前述のように、バイポーラトランジスタ404を使用したエミッタフォロワ回路、ダイオード406を使用した回路、或いは、MOS型等のFETを使用したソースフォロワ回路とすることができる。基板電圧は安定していなければならないため基板制御回路402の出力をインピーダンス変換するエミッタフォロワ回路やソースフォロワ回路の出力回路を介すことが通常である。基板制御回路の出力インピーダンスが十分低い場合はダイオード406を使用できる。バイポーラトランジスタ404を使用した場合の電圧差ΔV403はバイポーラトランジスタ404のベース・エミッタ間電圧Vbeであり、ダイオード406を使用した場合の電圧差ΔV403はダイオード406の順方向降下電圧であり、MOS型等のFETを使用した場合の電圧差ΔV403はソースフォロワ回路による電圧差分となる。
本実施形態の撮像装置1の保護装置400の動作について説明する。以下では、第3電位V3は、電圧値が最大許容条件(V3max>-VLmin+VFmin)を満たし、電源起動時には固体撮像装置10及び垂直ドライバ42Vの電源(第1電位VH、第2電位VL)が立ち上がる前に立ち上がるとともに、電源遮断時には固体撮像装置10及び垂直ドライバ42Vの電源が立ち下がった後に立ち下がる電源から供給されるものとする。
先ず、電源起動時の動作について説明する。図7に示すように、固体撮像装置10及び垂直ドライバ42Vへの電源(第1電位VH用及び第2電位VL用)が立ち上がる前に、第3電位V3が立ち上げられる。第3電位V3が立ち上がると、ダイオード414に順方向降下電圧がかかりオンするので電流が流れ、その結果、固体撮像装置10の基板電圧端子φSUBには、ダイオード414から抵抗素子416に流れる電流値に応じた電圧が発生する。
次に、通常の動作について説明する。通常動作時、垂直ドライバ42Vのシャッタ端子SUBから出力された電子シャッタドライブパルスΦSHTの交流成分が固体撮像装置10の基板電圧端子φSUBに入力される。このとき、ダイオード414は常に逆バイアスがかかりオフしている。参考構成1のダイオード424や参考構成2~参考構成4のダイオード414のような特殊で高価なダイオードは必要でない。例えば、参考構成2~参考構成4では、順バイアスのダイオード414に、逆バイアスの交流信号が入力されるため、逆回復時間の速いダイオードを必要とするのと異なる。
次に、電源遮断時の動作について説明する。図7に示すように、第3電位V3が立ち下がる前に、駆動電源46は、固体撮像装置10及び垂直ドライバ42Vへの電源(第1電位VH用及び第2電位VL用)を立ち下げる。電源電圧(第1電位VH及び第2電位VL)が下降して、基板電圧端子φSUBが、第3電位V3-ダイオード414の順方向降下電圧VF以下になると、ダイオード414が順方向動作するようになるので電流が流れる。その結果、固体撮像装置10の基板電圧端子φSUBには、ダイオード414から抵抗素子416に流れる電流値に応じた電圧が発生するので、基板電圧端子φSUBは一定の電圧にクランプされる。
以上のように、本実施形態の保護装置400によれば、部品数が少なく簡単な構成によって、電源の起動時や遮断時に、CCD等の固体撮像装置10の半導体基板に異常電圧(具体的には基準電位VMに対して第2の方向(マイナス方向)の電圧)が印加されることを防止することができる。本実施形態の保護装置400は、垂直ドライバ42Vと固体撮像装置10との間の直流除去を行なう部材としてコンデンサ412のみを使用しているので、直流成分の除去が1回で済む。このため、コンデンサ412の容量値を小さくできるし、より小さな部品(例えば0603サイズの超小型のセラミックコンデンサ等)を選択できるし、更には、固体撮像装置10の基板電圧制御にかかる遷移時間を短縮できる。更には、本実施形態の保護装置400によれば、コンデンサ412の両端電圧を抑制することができるため、コンデンサ412におけるDCバイアス依存性の影響も受け難いし、定常電流も必要としないので特別なダイオードを必要としない。
実施例1~実施例3では、保護装置400のダイオード414のアノード端の接続先を水平ドライバ42Hの電源端とすることにより、水平ドライバ42H用の電源を第3電位V3用の電源に利用していたが、第3電位V3用の電源に利用できるのは、水平ドライバ42H用の電源には限らない。例えば、同じくドライバ42内に実装されているレベルシフト部42LS、水平出力ドライバ42HRG、或いは、水平最終段ドライバ42LH等の垂直ドライバ42Vを除く機能部用の電源を利用してもよい。或いは、図11に示すように、固体撮像装置10の出力回路として機能する電荷・電気信号変換部16用の電源を利用してもよい。何れの変形例も、保護装置400の近傍に配置されるドライバ42或いは固体撮像装置10用の電源を利用するので配線の引き回しの不都合はない。尚、図11は実施例1の構成に対する変形例で示しているが、実施例2及び実施例3に対しても同様の変形を適用できる。又、これらの各電源を任意に選択可能に構成してもよい。この場合、実態に合わせて最適な電源を選択して第3電位V3用の電源として利用することができる。ドライバ42内の各電源を切替使用する構成にすることは簡単に実現できる。
[付記1]
第1極性の半導体に電圧のパルスが印加される固体撮像装置と、
固体撮像装置の駆動パルスを出力するパルス駆動部と、
パルス駆動部と固体撮像装置との間に配置されている保護部、
とを備え、
保護部は、パルス駆動部の出力端と固体撮像装置の電圧端子との間に接続されたコンデンサ、電位点と電圧端子との間に接続されたダイオード、及び、電圧端子と電位点との間に接続された抵抗素子を有し、
ダイオードのアノード端が、電圧端子の電位が印加される電位点に接続されており、
固体撮像装置への電源起動時には、その電源起動よりも前に電位点の電位が起動する撮像装置。
[付記2]
電位点には、電圧端子の最大定格電圧と対応している電位が印加される付記1に記載の撮像装置。
[付記3]
電位点には、電圧端子の定格電圧とダイオードの順方向降下電圧との和を下回る電位が印加される付記1又は付記2に記載の撮像装置。
[付記4]
電位点には、電圧端子の最小許容電圧とダイオードの順方向降下電圧との和を下回る電位が印加される付記3に記載の撮像装置。
[付記5]
電位点には、電圧端子の定格電圧とダイオードの順方向降下電圧の最小値との和を下回る電位が印加される付記1乃至付記4の何れか1項に記載の撮像装置。
[付記6]
電位点には、電圧端子の最小許容電圧とダイオードの順方向降下電圧の最小値との和を下回る電位が印加される付記5に記載の撮像装置。
[付記7]
パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
垂直パルス駆動部と固体撮像装置への電源起動時には、その電源の起動よりも前に電位点の電位が起動する付記1乃至付記6の何れか1項に記載の撮像装置。
[付記8]
固体撮像装置用の電源として、第1極性と対応する電位であって基準電位に対して第1の方向の第1電位及び基準電位に対して第1の方向とは逆の第2の方向の第2電位を出力するものが使用され、
電源起動時には、第1電位が起動した後に第2電位が起動する付記1乃至付記7の何れか1項に記載の撮像装置。
[付記9]
固体撮像装置への電源遮断時には、その電源が遮断した後に電位点の電位が遮断する付記1乃至付記8の何れか1項に記載の撮像装置。
[付記10]
固体撮像装置用の電源として、第1極性と対応する電位であって基準電位に対して第1の方向の第1電位及び基準電位に対して第1の方向とは逆の第2の方向の第2電位を出力するものが使用され、
電源遮断時には、第2電位が遮断した後に第1電位が遮断する付記9に記載の撮像装置。
[付記11]
パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
電位点は、水平パルス駆動部用の電源と接続されている付記1乃至付記10の何れか1項に記載の撮像装置。
[付記12]
固体撮像装置は、撮像信号を出力する出力部を有し、
電位点は、出力部用の電源と接続されている付記1乃至付記10の何れか1項に記載の撮像装置。
[付記13]
電位点は、固体撮像装置用及びパルス駆動部用以外の機能部用の電源と接続されている付記1乃至付記10の何れか1項に記載の撮像装置。
[付記14]
電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、固体撮像装置内に実装されている付記1乃至付記13の何れか1項に記載の撮像装置。
[付記15]
電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、パルス駆動部内に実装されている付記1乃至付記13の何れか1項に記載の撮像装置。
[付記16]
電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、固体撮像装置及びパルス駆動部の外部に配置されている付記1乃至付記13の何れか1項に記載の撮像装置。
[付記17]
保護部は、抵抗素子と並列接続されたコンデンサを有する付記1乃至付記16の何れか1項に記載の撮像装置。
[付記18]
第1極性の半導体に電圧のパルスが印加される固体撮像装置を保護する保護装置であって、
固体撮像装置の駆動パルスを出力するパルス駆動部と固体撮像装置との間に配置されており、
パルス駆動部の出力端と固体撮像装置の電圧端子との間に接続されたコンデンサ、電位点と電圧端子との間に接続されたダイオード、及び、電圧端子と電位点との間に接続された抵抗素子を有し、
ダイオードのアノード端が、電圧端子の電位が印加される電位点に接続されており、
固体撮像装置への電源起動時には、その電源起動よりも前に電位点の電位が起動する固体撮像装置の保護装置。
[付記19]
パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
垂直パルス駆動部と固体撮像装置への電源起動時には、その電源の起動よりも前に電位点の電位が起動する付記18に記載の保護装置。
[付記20] 固体撮像装置への電源遮断時には、その電源が遮断した後に電位点の電位が遮断する付記18又は付記19に記載の保護装置。
Claims (20)
- 第1極性の半導体に電圧のパルスが印加される固体撮像装置と、
固体撮像装置の駆動パルスを出力するパルス駆動部と、
パルス駆動部と固体撮像装置との間に配置されている保護部、
とを備え、
保護部は、パルス駆動部の出力端と固体撮像装置の電圧端子との間に接続されたコンデンサ、電位点と電圧端子との間に接続されたダイオード、及び、電圧端子と電位点との間に接続された抵抗素子を有し、
ダイオードのアノード端が、電圧端子の電位が印加される電位点に接続されており、
固体撮像装置への電源起動時には、その電源起動よりも前に電位点の電位が起動する撮像装置。 - 電位点には、電圧端子の最大定格電圧と対応している電位が印加される請求項1に記載の撮像装置。
- 電位点には、電圧端子の定格電圧とダイオードの順方向降下電圧との和を下回る電位が印加される請求項1に記載の撮像装置。
- 電位点には、電圧端子の最小許容電圧とダイオードの順方向降下電圧との和を下回る電位が印加される請求項3に記載の撮像装置。
- 電位点には、電圧端子の定格電圧とダイオードの順方向降下電圧の最小値との和を下回る電位が印加される請求項1に記載の撮像装置。
- 電位点には、電圧端子の最小許容電圧とダイオードの順方向降下電圧の最小値との和を下回る電位が印加される請求項5に記載の撮像装置。
- パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
垂直パルス駆動部と固体撮像装置への電源起動時には、その電源の起動よりも前に電位点の電位が起動する請求項1に記載の撮像装置。 - 固体撮像装置用の電源として、第1極性と対応する電位であって基準電位に対して第1の方向の第1電位及び基準電位に対して第1の方向とは逆の第2の方向の第2電位を出力するものが使用され、
電源起動時には、第1電位が起動した後に第2電位が起動する請求項1に記載の撮像装置。 - 固体撮像装置への電源遮断時には、その電源が遮断した後に電位点の電位が遮断する請求項1に記載の撮像装置。
- 固体撮像装置用の電源として、第1極性と対応する電位であって基準電位に対して第1の方向の第1電位及び基準電位に対して第1の方向とは逆の第2の方向の第2電位を出力するものが使用され、
電源遮断時には、第2電位が遮断した後に第1電位が遮断する請求項9に記載の撮像装置。 - パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
電位点は、水平パルス駆動部用の電源と接続されている請求項1に記載の撮像装置。 - 固体撮像装置は、撮像信号を出力する出力部を有し、
電位点は、出力部用の電源と接続されている請求項1に記載の撮像装置。 - 電位点は、固体撮像装置用及びパルス駆動部用以外の機能部用の電源と接続されている請求項1に記載の撮像装置。
- 電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、固体撮像装置内に実装されている請求項1に記載の撮像装置。 - 電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、パルス駆動部内に実装されている請求項1に記載の撮像装置。 - 電圧端子に所定電位を印加する基板電圧制御回路を備え、
基板電圧制御回路は、固体撮像装置及びパルス駆動部の外部に配置されている請求項1に記載の撮像装置。 - 保護部は、抵抗素子と並列接続されたコンデンサを有する請求項1に記載の撮像装置。
- 第1極性の半導体に電圧のパルスが印加される固体撮像装置を保護する保護装置であって、
固体撮像装置の駆動パルスを出力するパルス駆動部と固体撮像装置との間に配置されており、
パルス駆動部の出力端と固体撮像装置の電圧端子との間に接続されたコンデンサ、電位点と電圧端子との間に接続されたダイオード、及び、電圧端子と電位点との間に接続された抵抗素子を有し、
ダイオードのアノード端が、電圧端子の電位が印加される電位点に接続されており、
固体撮像装置への電源起動時には、その電源起動よりも前に電位点の電位が起動する固体撮像装置の保護装置。 - パルス駆動部は、垂直転送系の駆動パルスを出力する垂直パルス駆動部と、水平転送系の駆動パルスを出力する水平パルス駆動部とを有し、
垂直パルス駆動部と固体撮像装置への電源起動時には、その電源の起動よりも前に電位点の電位が起動する請求項18に記載の保護装置。 - 固体撮像装置への電源遮断時には、その電源が遮断した後に電位点の電位が遮断する請求項18に記載の保護装置。
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US14/124,295 US9113099B2 (en) | 2011-07-08 | 2012-06-29 | Imaging device and protection device of solid-state imaging device |
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US6570370B2 (en) * | 2001-08-21 | 2003-05-27 | Raven Technology, Llc | Apparatus for automatic tuning and control of series resonant circuits |
EP1513377A1 (en) * | 2002-06-07 | 2005-03-09 | Matsushita Electric Industrial Co., Ltd. | Electrodeless light bulb type fluorescent lamp and discharge lamp lighting device |
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EP1979598B1 (de) * | 2006-01-24 | 2011-03-23 | Continental Automotive GmbH | Vorrichtung zum schalten induktiver kraftstoff-einspritzventile |
JP5218269B2 (ja) * | 2009-05-13 | 2013-06-26 | ソニー株式会社 | 表示装置および駆動制御方法 |
JP5501851B2 (ja) * | 2010-05-12 | 2014-05-28 | Tone株式会社 | 位相制御装置 |
JP5505286B2 (ja) * | 2010-12-03 | 2014-05-28 | 富士通株式会社 | 差動増幅回路 |
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JPH07284026A (ja) * | 1994-04-11 | 1995-10-27 | Sony Corp | 固体撮像装置 |
JP2005123712A (ja) * | 2003-10-14 | 2005-05-12 | Matsushita Electric Ind Co Ltd | 固体撮像装置の垂直転送駆動装置 |
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US20140118594A1 (en) | 2014-05-01 |
KR101966473B1 (ko) | 2019-04-05 |
TWI524765B (zh) | 2016-03-01 |
CN103636193B (zh) | 2017-06-09 |
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