Originally shared by Dushyant Ahuja Can someone please look at my PCB - it's

Electronics
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Originally shared by Dushyant Ahuja

Can someone please look at my PCB - it’s my first one, and the circuit is pretty simple.

However, when I soldered the components in and programmed the ESP8266, for some reason all the pins of the ESP8266 go high as soon as I power on the circuit and the ESP heats up immediately.

I picked up another board and ESP-12F module and installed just the ESP-12F, and the pull-up/pull-down resistors. Same result. Not sure what I did wrong, but would be great is someone can have a quick look.

Thanks

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I am not sure why all the pins are going high on power up, but gpio15 will draw high current if is configured as an output. Also I don’t believe that you should use gpio9 and 10 because they’re used for the internal flash memory chip.

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@Secord_Michael I have gpio 15 tied to ground and have not broken it out on the board. I’ll keep 9/10 in mind. Thanks.

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where is 3.3V supply for esp?? I see only 5v regulator. Dont you power your esp by 5v when NOT in programm mode??

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Conn_01x03 is for the 3.3v converter

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Thanks everyone for your help - found the issue - even though the ESP-12’s GND PIN in the schematic was connected, it was floating in the actual board layout. Not sure why that happened as KiCAD did not show any unconnected pads. Shorting the GND to pin 15 (which was already connected to the ground plane) sorted the issue.

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Hi
74hct245 is just a buffer to get the pins to 5v in this case.
This is not to good. You would want the gate voltage to go higher than that according to the fets data sheet. Also the puldowns are redundant since your outputs are always eabled (transient behaviour is negligable). Better use a small vgs mosfet or darlington bippolar on the esp outputs to get a higher gate voltage.