Comparator, AD converter, solid-state imaging device, electronic apparatus, and method of controlling comparator

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal, wherein the comparison unit includes at least a first transistor to which the input signal is input, and a second transistor to which the reference signal is input;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a number pixels, wherein:
• each pixel includes a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering each respective pixel and photoelectrically converting the light, wherein:
• the comparator is provided for each pixel circuit,
• the voltage of the reference signal to be input to the second transistor is set at a predetermined voltage to make at least one pixel circuit non-selected,
• the first transistor and the second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a number of pixels, wherein:
• each pixel includes a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering each respective pixel and photoelectrically converting the light, wherein:
• the comparator is provided for each pixel circuit,
• a plurality of the pixels are simultaneously read with a combination of color filters, a color of the combination of the color filters being white,
• a first transistor and a second transistor disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a number of pixels, wherein each of the pixels includes a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering the respective pixel and photoelectrically converting the light, wherein:
• the comparator is provided for a plurality of the pixel circuits,
• simultaneously-read pixels form one image,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a number of pixels, wherein each of the pixels includes a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering the respective pixel and photoelectrically converting the light, wherein:
• the comparator is provided for M of the pixel circuits;
• M is greater than one;
• and
• after outputting the input signal at a reset level of the M pixel circuits to the comparison unit, the M pixel circuits sharing the comparator output the input signal at a signal level of the M pixel circuits to the comparison unit,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering a pixel and photoelectrically converting the light, wherein:
• a pixel array unit in which a plurality of the pixels are two-dimensionally arranged is divided into a plurality of areas;
• the voltage of the reference signal is controlled in each of the areas,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering a pixel and photoelectrically converting the light, wherein:
• the storage unit includes a P-phase storage unit configured to store the code output signal at a reset level of the pixel and a D-phase storage unit configured to store the code output signal at a signal level of the pixel;
• the P-phase storage unit and the D-phase storage unit simultaneously output the code output signal at the reset level of the pixel and the code output signal at the signal level;
• a first transistor and a second transistor are disposed on a first semiconductor substrate;
• and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering a pixel and photoelectrically converting the light, wherein:
• the pixel circuit includes a transistor configured to change a capacitance of a floating diffusion layer holding the charge signal until the charge signal is output to the comparison unit,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an AD converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• and
• a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering a pixel and photoelectrically converting the light, wherein:
• a frequency of the code input signal is changed at least once in one vertical scan period,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A solid-state imaging device comprising:

• an analog-to-digital (“AD”) converter including:
• a comparator including:
• a comparison unit configured to compare a voltage of an input signal with a voltage of a reference signal and output a comparison result signal;
• and
• a positive feedback circuit configured to increase a speed of transition at a time when the comparison result signal is inverted;
• and
• a storage unit configured to store a code input signal at the time when the comparison result signal is inverted and output the code input signal as a code output signal;
• a pixel circuit configured to output a charge signal as the input signal to the comparison unit, the charge signal having been generated by receiving light entering a pixel and photoelectrically converting the light;
• and
• a code reading unit configured to read the code output signal stored in the storage unit by performing a precharge operation and a read operation, wherein:
• the code reading unit performs the read operation when an adjacent code reading unit is performing the precharge operation,
• a first transistor and a second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.

A comparator comprising:

• a comparison unit configured to output a comparison result signal based on a comparison of a voltage of an input signal with a voltage of a reference signal, wherein:
• the comparison unit includes at least a first transistor to which the input signal is input and at least a second transistor to which the reference signal is input,
• the first transistor is connected to a floating diffusion layer of a pixel circuit, and
• the voltage of the reference signal is set at a predetermined voltage to reset the floating diffusion layer of the pixel circuit;
• and
• a positive feedback circuit configured to increase a speed of transition when the comparison result signal is inverted, wherein:
• when the comparison result signal is inverted a code input signal is stored in a storage unit,
• the first transistor and the second transistor are disposed on a first semiconductor substrate, and
• the positive feedback circuit is disposed on a second semiconductor substrate.