My main goals right now are to...jph wrote: ↑Mon Sep 26, 2022 1:55 pm 1, yes, sort of ... it means that if you just connected the source and drain and left the gate floating the device would be OFF and no current would flow. In this circuit, we need to make the 'gate' negative in respect of the 'source' (14V) so we need to have a PD (Potential difference) of > 13V BELOW the source so in this circuit we already have a spare open collector transistor in a spare gate of the ULN, by connecting the gate to this we can, when there is a logic one on the ULN channel input, turn on the ULN darlington transistor (a low-side driver) which then pulls the gate down to gnd (or near enough) so we now have a PD of around 13V between source and gate - where gate is minus 13v LOWER. The device - the MOSFET - will now conduct and is in it's NON linear region so we get advantage of the extremely low Rds ON resistance. We do not want to be anywhere near the linear region - power mosfets are simply not designed to be run in the linear region. !!
2. Excellent on the dimmers. They dont have to be on the same device even. Just providing AM can see them.
What do they do at the moment ? - what do they operate ?
1. Finish up the autopilot switch / magnet coding.
2. Then develop a way to turn off the gear lights when I toggle my hardware battery switch to off. (MOSFET)