Embedded Lab

Measuring the frequency of a signal may seem to be a simple process of counting pulses, but in order to get better accuracy, few other things should be considered, such as the gating interval and the range of measurement. This tutorial, posted on the pcbheaven.com, briefly describes two typical methods of frequency measurement: Direct Frequency Measuring (DFM) and the Reverse Frequency Measuring (RFM), with their pros and cons.

The shape of the incoming signal may be distorted and of varying amplitude. Therefore, some sort of signal conditioning along with a voltage limiter is required prior to the frequency counter circuit.