I am working with an IR sensor which gives the following output once the sensor is actuated. The sensor creates a negative pulse followed by a positive pulse. The pulses each are approximately 10 ms wide. These pulses are approximately 1 sec apart. Two pulses constitute one single output event.
I am reading this signal in LabVIEW cDAQ device using an analog voltage input module. My goal is to drive a digital output high in LabVIEW software when the event occurs (at the end of positive pulse). Another way to say is I want to completely ignore all negative going pulses and overshoots and I only want to observe the first positive going pulse. Once observed I want to drive a digital output high in LabVIEW.
I don't have good knowledge in signal processing. My thought is I need to filter out the negative pulse and overshoots. Then I can use filter to detect the positive pulse and drive a digital output high. I want to leverage the signal processing tools in LabVIEW but I don't know how to design filter circuit.
I would appreciate any direction on how to design the circuit with the help of LabVIEW signal processing tools. Thank you so much!
Best Answer
A positive edge trigger SR flip-flop can solve the problem. For Reset input providing a 0 and for S input providing the signal which resembles a clock signal. Q will toggle to 1 for positive edge of the clock input.