what is the safest way to power vin pin to feather esp32 v1 (huzzah)?

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icq4ever
 
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what is the safest way to power vin pin to feather esp32 v1 (huzzah)?

Post by icq4ever »

I designed custom version of huzzah with external antenna esp32.
original one has battery JST pin but I remove it and instead of that add external 5Vpin(ext5v) connect to GMD3415 mosfet pin no 3.
so it can serial communication while it powered by ext 5V.

but, when ext5V connected without connect usb, there's ~1V between VBUS and GND.
how can I fix this issue? should I connect extra diode between VBUS and DMG3415 pin 1?
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adafruit_support_mike
 
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Re: what is the safest way to power vin pin to feather esp32 v1 (huzzah)?

Post by adafruit_support_mike »

You're probably seeing reverse leakage current through the MBR120 diode.

That's a known issue: diodes with low forward voltage have higher reverse leakage. In fact, if you get down into the physics, the low forward voltage happens -because- of the higher reverse leakage.

With a 100k pull-down on VBUS, 4V represents leakage of about 40uA. That isn't enough to damage anything.

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