what is the frequency measure accuracy by using InfiniiVision 2000 Series?
It depends... The frequency measurement is actually 1/period. The scope measures the period and inverts the results to get frequency. The relevant spec is delta time accuracy, from the datasheet :
± (time base accuracy reading) ± (0.0016 screen width) ± 100 ps
This is essentially an RMS value, and since you have to look at two edges to make a period measurement, you need to multiply this by sqrt(2) or ~1.414
So... The answer will vary, based on the frequency of the signal and the noise (either on the signal or in the scope).
Does this help?
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