On Mon, Jan 6, 2014 at 10:49 PM, RussellMc wrote: > Beware that vthere are L and FP versions I was looking at the L version, but... > http://www.st.com/web/en/resource/technical/document/datasheet/CD00003408= ..pdf > At 5V it's staggering into life - fig 5, 2V Vds at 8A typical - not nice= - > there are many more that are properly on at 5V and a lot that can be driv= en > with 3V. > > L version is better - but better again can be had for similar $ > http://www.st.com/web/en/resource/technical/document/datasheet/CD00003405= ..pdf Ok, I'm definitely open for a better option. I'd rather get this right. > What Imax ever? For now, let's say 1A. It is entirely likely that it will never be that high though. > What Vmax ever? 12V. I'm going to try running everything at 5V first though. > SMD or through hole wanted.? Through hole for now. I'm taking an existing PCB, mounting it to some perf board, and wiring up the new additions. > What max PWM freq ever? Not high, maybe a few hundred Hz. > Vgs may be > Vds with no problems. > > 12V zener gate-source close to FET protects against most problems from > inductive load coupling into gate from Cdg Miller capacitance. Shouldn't be any inductive loads on this initially, though I will have to think about that if I end up switching relays or something like. > Direct PIC to gate drive allows only low freq PWM. DC switching OK. The existing PCB does have provision for a small jelly bean SO23 transistor on the PIC pin. NPN if I'm remembering correctly, but I'd have to check tomorrow to be sure. Useful in this case, or no? Thank you! Josh --=20 A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. -Douglas Adams --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .