| 摘要 |
<p>PROBLEM TO BE SOLVED: To measure a pulse width of a signal pulse with high precision in consideration of variations and fluctuations in delay time of delay elements.SOLUTION: A delay circuit provided comprises a plurality of delay elements connected in series to propagate a signal pulse which transitions from a first level to a second level and then transitions to the first level. A first number of stages of the delay elements which propagate the transition of the signal pulse to the second level is measured from that transition of the signal pulse to the start of a subsequent cycle of a clock signal, and the number of clock cycles of the clock signal is counted from the subsequent cycle of the clock signal to the transition of the signal pulse to the first level. A second number of stages of the delay elements which propagate the transition of the signal pulse to the first level is also measured from that transition of the signal pulse to the start of a subsequent cycle of the clock signal.</p> |
