Frequency comparator has status output

Posted on Oct 23, 2012    11789

The original application for the circuit in Figure 1 was to check the number of revolutions of an engine with only one LED as an indicator. The measurement of the number of revolutions usually involves sensors with a frequency output proportional to the number of revolutions. The circuit compares the frequency output of such a sensor with a lower and upper limit and gives a visual result, using one LED. If the frequency is below the lower limit, the LED remains unlit.

Leave Comment

characters left:

New Circuits