| 摘要 |
<p>A frequency and time measurement circuit is provided with a delay means (127) for effectively delaying the leading edge of a pulse. A register (131) is clocked by the trailing edge of the pulse to take a snapshot of how far the leading edge of the pulse has progressed through the delay means. During a calibration phase, a reference pulse of constant length is used to take a reference reading. During a measurement phase, the measurement reading is taken on the unknown pulse whose clock frequency or time period is to be determined. By comparing the reference reading with the measurement reading, the relative clock frequency or time of the unknown pulse can be determined.</p> |
