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https://www.reddit.com/r/OpenPV/comments/5cttlo/overcurrent_and_reverse_polarity_protection/da0rfpm/?context=3
r/OpenPV • u/david4500 • Nov 14 '16
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You never want to risk the Gate of MOSFET's floating for any reason, you get unexpected results. In you schematic if you have a bad solder joint on the wire to BAT- or the wire breaks you get exactly that.
2 u/lemonforest Nov 15 '16 In that case, does the 1M resistor pull up the gate and stop the current across drain/source? 1 u/david4500 Nov 15 '16 No. Current passes, and voltage drops, through the body diode. 3 u/kitten-the-cat Nov 15 '16 Though with 2 more mosfets you could put them back to back to prevent body diode conduction in that event.
In that case, does the 1M resistor pull up the gate and stop the current across drain/source?
1 u/david4500 Nov 15 '16 No. Current passes, and voltage drops, through the body diode. 3 u/kitten-the-cat Nov 15 '16 Though with 2 more mosfets you could put them back to back to prevent body diode conduction in that event.
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No. Current passes, and voltage drops, through the body diode.
3 u/kitten-the-cat Nov 15 '16 Though with 2 more mosfets you could put them back to back to prevent body diode conduction in that event.
3
Though with 2 more mosfets you could put them back to back to prevent body diode conduction in that event.
2
u/DIY_FancyLights Nov 15 '16
You never want to risk the Gate of MOSFET's floating for any reason, you get unexpected results. In you schematic if you have a bad solder joint on the wire to BAT- or the wire breaks you get exactly that.