摘要 |
Jitter is measured by applying a first clock signal to a device-under-test, measuring the phase difference between the jittered clock signal received from the device-under-test and a reference clock signal, and converting the phase difference to a jitter measurement. The phase difference is measured by counting the number of high frequency clock pulses between a transition of the jittered clock signal and a transition of the reference clock signal. The phase difference is converted to a jitter measurement by determining the highest and lowest phase difference count and taking the difference between the highest and lowest count. The phase of the reference clock signal can be adjusted as a function of the highest and lowest count by determined the mean value of the highest and lowest count and adjusting the reference clock to be of this mean value. The range of the jitter measurement can be adjusted by adjusting the frequency of high frequency clock to the counter, the jittered signal received from the device-under-test and the reference clock signal.
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