At 02:02 PM 3/12/2012, Spehro Pefhany wrote: >At 12:38 AM 12/03/2012, you wrote: > > >Many thanks for this little tidbit of information - I think that it > >just solved my problem! > >Glad to help, Dwayne. Thanks for stating the problem lucidly, succinctly, >and with enough detail to make it possible. I wound up ordering a couple of slightly different parts to try:=20 FDS4465 and SI4421. Both are in a so8 package (easier for me to=20 breadboard with) and both have RDSon ranging from 11 through 14=20 milliohms (2.5V to 1.8V gate drive). They cost a little more than=20 the SiA427 but the project volume is low enough that it just won't=20 matter in the end. I had previously spent a couple of days downloading, then searching=20 datasheets without finding anything even remotely close to these=20 devices. The key search term turned out to be "Trench", as in=20 'PowerTrench', 'TrenchFET', etc. Interestingly enough, I had previously searched for and found=20 DMP2035U-7 (sot-23) which is similar but not beefy enough: RDSon is a=20 worst case 62 milliohms @ 1.8V gate drive. That just wasn't going to=20 be reliable enough. It totally blows me away just how good MOSFETs are getting to be! Thanks again. dwayne --=20 Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .