DC-DC Chopper circuit problem

Discussion in 'The Projects Forum' started by cloud623, Jan 1, 2008.

  1. cloud623

    Thread Starter New Member

    Dec 16, 2007
    please anyone can help me check this circuit? because i cannot get the 60V waveform, just 2.8Vp-p. and which diode using in this circuit? zener, schottky or normal diode?
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    The diode is a 1N4001, which is as normal as you can get.

    What is driving the PWM waveform? Whatever is is, the current through the IRLED in the optocoupler must not exceed 20 ma.
  3. mrmeval

    AAC Fanatic!

    Jun 30, 2006
    http://octopart.com/search?q=1n4001&c=0&d=0 For the diode specs

    As beenthere says optocouple needs a resistor to current limit it. I'd suggest just shorting q2 base to ground and see if it works. If it works the opto is bad or your pwm is wrong.

    Strange looking circuit, where is it from?