>A Peltier device doesn't inherently care about ripple, but >it does get less efficient as the AC component increases. OK, thanks Olin. I do remember there was some discussion about it a while back, but seeing this is going on a spacecraft it looks like I best take "reasonable care" with the output. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist