To prevent the black dot phenomenon from occurring in a differential amplification-type solid-state image sensor.

A signal-side amplifier transistor generates an output voltage corresponding to a signal current corresponding to one of a pair of differential input voltages by supplying the signal current from an output node to a common-phase node. A reference-side amplifier transistor supplies a reference current corresponding to the other one of the pair of differential input voltages to the common-phase node. A constant current source constantly controls a sum of the signal current and the reference current to be merged at the common-phase node. A bypass control unit connects the output node and the common-phase node and supplies the signal current having a value corresponding to a predetermined limit voltage to the common-phase node in a case in which the output voltage reaches the limit voltage.

An image sensor includes a pixel array including a plurality of pixels operating in a plurality of modes, a readout circuit configured to receive a pixel signal corresponding to each of the plurality of modes from each of the pixels and generate a pixel value that is a digital signal from the pixel signal, and a signal processor configured to determine whether a target pixel value is a black spot generation value for each of the pixels based on at least one of comparison pixel values of each comparison mode among a plurality of comparison modes having a smaller output gain than a target mode corresponding to the target pixel value, and correct the target pixel value when the target pixel value is the black spot generation value.

An image sensor includes a pixel array including a plurality of pixels operating in a plurality of modes, a readout circuit configured to receive a pixel signal corresponding to each of the plurality of modes from each of the pixels and generate a pixel value that is a digital signal from the pixel signal, and a signal processor configured to determine whether a target pixel value is a black spot generation value for each of the pixels based on at least one of comparison pixel values of each comparison mode among a plurality of comparison modes having a smaller output gain than a target mode corresponding to the target pixel value, and correct the target pixel value when the target pixel value is the black spot generation value.

A plurality of pixels PX include effective pixels and optical black pixels. Signal lines VL are provided corresponding to each column of the pixels PX and supplied with output signals of the pixels PX of the corresponding column. Clip transistors CL are provided corresponding to the respective signal lines VL and limit a potential of the corresponding vertical signal lines VL based on a gate potential. At least in a predetermined operating mode, a potential Vclip_dark is supplied to a gate of one of the clip transistors CL corresponding to at least one pixel column formed of the optical black pixels when reading a noise level from the pixels PX corresponding to the clip transistors CL and when reading a data level from the pixels PX corresponding to the clip transistors CL.

A digital double-sampling (DDS) circuit includes a comparator with input nodes respectively connected to a ramp voltage and an image output node of a pixel circuit via a capacitor; a reset switch connected between the input nodes for resetting the capacitor; an analog-to-digital converter (ADC) coupled to receive a comparison output of the comparator, the ADC including a counter that counts while the ramp voltage is ramping, thereby generating a reset-ADC value in a reset phase and generating a signal-ADC value in a signal phase; a subtractor that subtracts the reset-ADC value from the signal-ADC value, thereby resulting in a difference value representing a sampled output; and a clamp circuit that generates a clamp voltage at the image output node. In the reset phase, the clamp circuit is disabled after the capacitor finishes resetting but before the ramp voltage begins ramping.

There is provided an imaging device including: a pixel that outputs a pixel signal corresponding to an amount of incident light; an output signal line that is connected to the pixel to allow the pixel signal from the pixel to be output to the output signal line; a first transistor that has a first gate, a first source, and a first drain, one of the first source and the first drain being connected to the output signal line; and a first circuit that is connected to the first gate, the first circuit being configured to generate a third voltage that is a voltage between a first voltage and a second voltage, the first voltage being a voltage for turning on the first transistor, the second voltage being a voltage for turning off the first transistor.

To prevent the black dot phenomenon from occurring in a differential amplification-type solid-state image sensor. A signal-side amplifier transistor generates an output voltage corresponding to a signal current corresponding to one of a pair of differential input voltages by supplying the signal current from an output node to a common-phase node. A reference-side amplifier transistor supplies a reference current corresponding to the other one of the pair of differential input voltages to the common-phase node. A constant current source constantly controls a sum of the signal current and the reference current to be merged at the common-phase node. A bypass control unit connects the output node and the common-phase node and supplies the signal current having a value corresponding to a predetermined limit voltage to the common-phase node in a case in which the output voltage reaches the limit voltage.

A pixel cell and readout circuit includes an anti-eclipse voltage clamp circuit at both the top and bottom of each column line of an array of the pixel cells. The anti-eclipse voltage clamp circuits form a row with each column in the array coupled to an anti-eclipse voltage clamp circuit. The combination of two rows of anti-eclipse voltage clamp circuits helps settle the clamp voltage more rapidly and to compensate for the increased length of the anti-eclipse voltage circuit row as well as the column line resistance due to narrow metal lines and increased numbers of pixels as well as the requirement to operate a sensor at a higher frame rate. More significantly this circuit construction can minimize vertical shading in the resulting image.

A plurality of pixels PX include effective pixels and optical black pixels. Signal lines VL are provided corresponding to each column of the pixels PX and supplied with output signals of the pixels PX of the corresponding column. Clip transistors CL are provided corresponding to the respective signal lines VL and limit a potential of the corresponding vertical signal lines VL based on a gate potential. At least in a predetermined operating mode, a potential Vclip_dark is supplied to a gate of one of the clip transistors CL corresponding to at least one pixel column formed of the optical black pixels when reading a noise level from the pixels PX corresponding to the clip transistors CL and when reading a data level from the pixels PX corresponding to the clip transistors CL.

A plurality of pixels PX include effective pixels and optical black pixels. Signal lines VL are provided corresponding to each column of the pixels PX and supplied with output signals of the pixels PX of the corresponding column. Clip transistors CL are provided corresponding to the respective signal lines VL and limit a potential of the corresponding vertical signal lines VL based on a gate potential. At least in a predetermined operating mode, a potential Vclip_dark is supplied to a gate of one of the clip transistors CL corresponding to at least one pixel column formed of the optical black pixels when reading a noise level from the pixels PX corresponding to the clip transistors CL and when reading a data level from the pixels PX corresponding to the clip transistors CL.