Nice SMT fun. (I hate SMT).I did discover a few things that help though, one is that sliding very thin feeler gauges under a part can help with removal. Another is that reflow with plenty of solder done swiftly work well, while holding the whole board at an angle that makes use of gravity to help run the excess solder off the pins. Use a flux pen too. Whole rows of very finely packed pins can be handled in a short moment like this. If a pin fails to bond, it's easy to retry the whole row.
A thing about FET's.. While they take very little current on the gate in a held state, the state change current can be very short and sharp if the input changes fast enough. I remember convincing Maplin to refund me for three Seimens touch dimmer chips (expensive) when I showed that their design diagram should have contained a 100R current limit resistor from chip to triac gate. (But they never reprinted the diagram in future catalogs so I bet other people got stung). While power FET's are not triacs, I think the same thing might work to protect the controlling device's output, and the input to the power stage. Just watch that the resistance isn't so high that it prevents fast modulation.
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Originally Posted by dnar
