On Fri, Aug 22, 2008 at 3:36 PM, Denny Esterline wrote: > I'm looking for sugestions for this bit of analog design. I need to run an > optocoupler, but the end user could connect it to about anything. It could > vary between 12 and 240 volts both AC or DC of unknown polarity. I only need > an off/on indication and if I get pulses from the zero crossings, I don't > mind. > > The best I have at the moment is in the attached schematic, but every time I > look at it I think it's over complicated. Any sugestions? > > Thanks, > Denny > Not sure if it's much simpler, but you could put the current limiter inside a full-bridge rectifier. Regards, Mark markrages@gmail -- Mark Rages, Engineer Midwest Telecine LLC markrages@midwesttelecine.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist