Patent ID: 7667633
Filing Date: 2010-02-23
Classification: G04F

Abstract:
1. A time-to-digital converter comprising: a low resolution time-to-digital converter for measuring a time difference between first and second signals with a first quantization step; and a high resolution time-to-digital converter for measuring the time difference between the first and second signals with a second quantization step that is smaller than the first quantization step; wherein the high resolution time-to-digital converter includes: a first high resolution transmission line comprised of first resistors that are serially connected for transmitting the first signal; a second high resolution transmission line comprised of second resistors that are serially connected for transmitting the second signal; a plurality of comparators, each comparing a respective first voltage of a respective first node of the first high resolution transmission line and a respective second voltage of a respective second node of the second high resolution transmission line; and an encoder for generating a high resolution digital code from outputs of the comparators.