Circuit and method for calibration of analog-to-digital converter

摘要

An analog-to-digital converter is provided. Each pre-amplifier provides a pair of differential outputs according to a pair of differential analog input signals and a first reference voltage and a second reference voltage from a resistor chain, wherein the first reference voltage is different from the second reference voltage. Each dynamic comparator provides a first comparing signal and a second comparing signal according to the pair of differential outputs of the pre-amplifier. Each pre-amplifier includes a first calibration unit for calibrating a first offset voltage from the pre-amplifier at the pair of differential outputs at a specific temperature, and a second calibration unit for calibrating a second offset voltage from the corresponding dynamic comparator at the pair of differential outputs.

主权项

1. An analog-to-digital converter, comprising:
a plurality of resistors forming a resistor chain; a plurality of pre-amplifiers, each providing a pair of differential outputs according to a pair of differential analog input signals and a first reference voltage and a second reference voltage from the resistor chain, wherein the first reference voltage is different from the second reference voltage; and a plurality of dynamic comparators coupled to the pre-amplifiers, each providing a first comparing signal and a second comparing signal according to the pair of differential outputs of the corresponding pre-amplifier, wherein each of the pre-amplifiers comprises:
a first calibration unit, for calibrating a first offset voltage from the pre-amplifier at the pair of differential outputs at a specific temperature; anda second calibration unit, for calibrating a second offset voltage from the corresponding dynamic comparator at the pair of differential outputs.