Without going down the whole reverse engineering, desgn calculation path, does someone have a simple, rule of thumb value for emitter resistors to promote current sharing in paralleled bipolar transistors ? Now that I actually need 5A out of my 5A bench supply (Wonix YW- APS305 from Dick Smith for those who may also have one), I find that they have 2 2N3055's in parallel (all three leads) and invariably, one of them cooks and dies. Pity they put thermal sensing on the other one. My immediate problem has been solved with the lead acid capacitor, but it would be nice to eliminate the problem for next time. Any top of the head values ? Thanks, Steve. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu