A/D converter and solid-state imaging apparatus with offset voltage correction

摘要

Provided is an A/D converter including an input terminal, a reference signal line for supplying a reference signal which changes temporally, a comparator, a correction capacitor connected to an inverting input terminal of the comparator; and an output circuit which outputs digital data corresponding to an analog signal input to the input terminal. In a first state in which a total voltage of a first analog signal and an offset voltage of the comparator is held in the correction capacitor, a second analog signal input to the input terminal is supplied to a non-inverting input terminal of the comparator, and the second analog signal or the total voltage is changed using the reference signal, thereby outputting, from the output circuit, digital data.

主权项

1. An A/D converter comprising:
an input terminal for inputting an analog signal; a reference signal line for connecting to a signal source that generates a reference signal which changes temporally; a comparator which includes a non-inverting input terminal, an inverting input terminal, and an output terminal, and outputs, from the output terminal, an output signal according to a comparison result between a voltage supplied to the non-inverting input terminal and a voltage supplied to the inverting input terminal; a correction capacitor connected to the inverting input terminal of said comparator; and an output circuit which outputs digital data corresponding to the analog signal input to said input terminal, wherein in a first state in which a total charge of a first analog signal and an offset voltage of said comparator is held in said correction capacitor, a second analog signal input to said input terminal is supplied to the non-inverting input terminal of said comparator, and the second analog signal supplied to the non-inverting input terminal of said comparator or the total voltage held in said correction capacitor is changed using the reference signal, thereby outputting, from said output circuit, digital data depending on a time from the beginning of the change until the output signal of said comparator changes as digital data corresponding to the second analog signal.