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These are boards I reverse engineer for my own understading.
The Unlicense
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Board Question #1

Open aerodev434 opened 4 years ago

aerodev434 commented 4 years ago

Hello, thank you very much for this schematic!

Hope you don't mind if I post a question here. On the D4184 board do you think this situation would cause a short: 1) Directly connecting Vout+ and Vout- by connecting a wire to both (at the screw terminal) 2) Connecting power to Vin+ and connecting Vin- to a Load, which is grounded to the chassis.

When the MOSFET is turned on, would this cause a short between the VOUT- (Drain) to VIN- (Source) and 5V GND. I suspect the buck converter does not provide isolation between the 5v gnd and 12v gnd.

It's this converter here: https://www.amazon.com/Regulator-DROK-Automotive-Waterproof-Transformer/dp/B081RMFSCG

I would certainly appreciate your or anyone else's input on this. Thanks!

I posted 2 diagrams. The first is the D4184 Connections The second is the whole circuit, the D4184 sits on the right side.

d4184-wrong

circuit

aerodev434 commented 4 years ago

Update: I tested the above, here's the finding:

Everytime the MOSFET is switched on with the above wiring configuration, it blows the fuse. This leads me to believe that the connection at the Drain (12V+ in this case) is being shorted to ground through the 5V GND line at J1 probably because the buck converter does not provide isolation.

I'm updating the image above with a note to not follow it.

I tried to remove the 5V GND line at J1, in this case the MOSFET does not seem to be conducting at all.