Successive approximation register analog-to-digital converter, and operating clock adjustment method therefor

Abstract

A successive approximation register analog-to-digital converter includes: a digital-to-analog converter to generate an analog voltage based on an input voltage sampled in accordance with a sampling clock and a digital code; a comparator to receive the analog voltage; a controller to generate the digital code based on an output of the comparator; a delay circuit to delay a signal based on the output of the comparator and to feed back the delayed signal to a reset terminal of the comparator; an adjustment circuit to count a number of edges of a signal generated in a loop that feeds back the delayed signal, and to adjust an amount of delay of the delay circuit based on a count value; and a sampling clock generation circuit to generate the sampling clock based on the signal generated in the loop and the external clock signal.