Time measurement device

摘要

A time measurement device for measuring a duration of an input signal based on a clock signal comprises a first gate for outputting a gate signal based on an input signal; a first holding circuit for holding the gate signal at the time of falling of the clock signal; a second holding circuit for holding the gate signal at the time of rising of the clock signal; a second gate for passing the clock signal according to either of the widths of output signals of the first and second holding circuits; a third holding circuit for holding an output state of the second holding circuit at the timing of a leading edge of an output of the first holding circuit; a fourth holding circuit for holding an output state of the second holding circuit at the timing of a trailing edge of an output of the first holding circuit; and a counter for counting the clock signal output from the second gate. The count value is corrected based on the outputs of the third and fourth holding circuits.