Propagation delay time measuring device

Abstract

A propagation delay time measuring device has a test signal generating circuit, a time measuring circuit, a data table and a calculation circuit. The test signal generating circuit generates a test signal and supplies the test signal to a measuring point which is connected to one of the terminals of a signal transmission line. The time measuring circuit receives a signal waveform at the measuring point. The signal waveforms indicates an waveform of the test signal supplied to one of the terminals of the signal transmission line and a waveform reflected by another terminal of the signal transmission line and returned to the measuring point. The time measuring circuit measures a time when the test signal is supplied to the measuring point and a time when the reflected waveform is returned to the measuring point based on the signal waveform at the measuring point. The data table stores correct data made up of propagation delay time data and measurement error data which are obtained by a simulation of the signal transmission line. The calculation circuit calculates a propagation delay time of the signal transmission line based on the times measured by the time measuring circuit and corrects the calculated propagation delay time based on the data table.

Dependencies are inferred from the claim text.