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I accidentally connected 9V battery to the CMD and 5V pins.

Posted: Tue May 12, 2020 9:42 pm
by Time7Portal
ESP_-_32_NodeMCU_Developmentboard_Pinout_Diagram.jpg
ESP_-_32_NodeMCU_Developmentboard_Pinout_Diagram.jpg (826.34 KiB) Viewed 5006 times
This is a pin-out of my board.

IMG_20200512_143031.jpg
IMG_20200512_143031.jpg (282.38 KiB) Viewed 5006 times
This is a board what I have..


Strangely, my board is mislabeled at the CMD location with "GND",
thus, I connected 9v (+) to the 5v header pin and 9v (-) to the CMD header pin which was mislabeled "GND" for about 10 seconds without any doubt.

The backlight was turned on the LCD, but only a black screen appeared, and the code did not work.

And when I touched the voltage regulator, it was very hot, so I detached 9v battery immediately.
The ESP32 module was also a bit warm.

After that happens, I couldn't find any problem with USB connection, WiFi, and all GPIOs for a day.
Will this ESP have any problems in the future?
Is it okay to continue using it?


Thank you for your help.

Re: I accidentally connected 9V battery to the CMD and 5V pins.

Posted: Wed May 13, 2020 6:32 am
by ESP_Sprite
Hard to say. If you are using that ESP32 board for a critical purpose, I'd throw it away. Seeing that it still works, it's probably is still usable as a devboard, but I would mark it as questionable so you won't be chasing red herrings if something turns out to be broken after all and you think it's a software bug.

Re: I accidentally connected 9V battery to the CMD and 5V pins.

Posted: Thu May 14, 2020 8:37 pm
by Time7Portal
ESP_Sprite wrote:
Wed May 13, 2020 6:32 am
Hard to say. If you are using that ESP32 board for a critical purpose, I'd throw it away. Seeing that it still works, it's probably is still usable as a devboard, but I would mark it as questionable so you won't be chasing red herrings if something turns out to be broken after all and you think it's a software bug.
Thank you for the recommendation.
I won't be using it for a critical purpose.