On Mon, Feb 28, 2011 at 3:07 PM, alan smith wrote: > I have a sensor, that when its activated, it goes from a 15ohm to open ci= rcuit. =A0This is a battery powered device, so low current is critical. It = will bounce back and forth, as its a motion detector of sorts. > > The approach I was going to take (and build up to test later) is to put a= 330K resistor in series being fed by the box 3.3V power, and connect the A= /D of the PIC between the sensor and the resistor. =A0Normally it will pull= some small amount of current and thus a voltage drop to measure, and on a = open circuit if course it should read zero. > > Any other ideas on measuring for an open circuit with very low power cons= umption? > Are you trying to measure on/off or a range of values? Regards, Mark markrages@gmail --=20 Mark Rages, Engineer Midwest Telecine LLC markrages@midwesttelecine.com --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .