On Tue, Aug 12, 2008 at 10:45 PM, Jinx wrote: > Just out of curiosity (and a little $$$ saving), is a capacitor > acceptable as a low-impedance "buffer" for inputs ? > I've tried that in the past, without success. I put a largish capacitor on the ADC input, but I still noticed a lot of noise in the reading. An op-amp buffer made the noise go away. My (speculative) theory is that the average input currents change depending on how the successive approximating goes and how much charge gets taken from C_hold. 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