38KHz IR detector persistance

Discussion in 'General Electronics Chat' started by jeffjohnvol, Mar 4, 2011.

  1. jeffjohnvol

    Thread Starter Member

    Oct 15, 2008
    Hello. I'm trying to create a circuit that reads the presence of a 38Khz signal. I have the sharp sensor, and I am not worried about transmitting.

    I will have 8 of these things that I want to pull in from a 165 shift register. A remote signal normally has a sequence of pulses coming in, and I don't care about the pulses, I just want to see if one is there.

    Given that I have to read the register each time, I am worried I'll catch a "trough" of the signal rather than the signal itself.

    Without building some complicated latch circuit, is there a simple resistor/cap combo I can use (or transistor) to hold the value for a very small while so I can see it? Almost like an electronic debounce circuit.

    Also, it would need to drain fast enough such as to not hold the line too long. I just need to bridge some of those troughs so I get a positive read.

    Thanks in advance.