WiFi Kit 32 v2 Fried?

#1

Hello.
Yesterday I was using a WiFi Kit 32 v2 board powered from a AMS1117-5.0V module like this:
https://es.aliexpress.com/item/4000171054458.html?spm=a2g0s.9042311.0.0.72a663c0yV0NzS
When I powered this module with a 12v power supply, the AMS1117-5 burned out and then the WiFi Kit 32 board turned unresponsive.
Looking at the schematics, it looks like the Fuse shouldn’t be failing because is used when powering from USB and I was injecting the 5v from AMS1117-5 directly to the +5v pin on the WiFi Kit 32 board, not passing by the USB.

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Now, when I try to power on the board from USB or from +5v pin, nothing happens.
I suspect from the ESD Protection diode RSB6.8S but I cannot find it on the board. Could be this component the cause of fail?
But also I have seen that the ESP32 works at 3.3v and it looks like the CE6260 Mosfet is the responsible of providing the 3.3v. When I power the board from USB, I can measure 1.96v in the +5v pin. And it looks like there is continuity between +3.3v and GND pins.
I am novice at electronics and I have no skills but I can measure with a tester and I am good at soldering. If anybody can help me, I would like to recover this board if is possible.
Thank you very much for your support and regards :slight_smile:

#2

I have made a test. I have powered the 3.3v pin with 2x1,5 AA Batteries in serial and still is unresponsive but I noticed some heat at the LTH7 (it looks like a lithium charger) that it is between the USB connector and the display.
Is possible that this one was burned when the AMS1117-5.0V blowed up?
Should I test any other component in order to find the failure?
Thanks in advance :slight_smile:

#4

I cannot find the CE6260 on the board. I have identified several 5 pin smds like A19T (TRANSISTOR SMD MOSFET AO3401 A19T -30V -4A 1.4W Canal P SOT-23) and LHT7 (Lithium charguer) and there are two more that I cannot find references. Both are in the bottom side of the board, one says “ZTt” and has 6 pins and another one says “9A26” and has 5 pins.
Any help to find the CE6260?

#5

Any idea about where can I locate the CE6260 on the WiFi Kit 32 v2?
Please help. I would like to recover it.
Thanks :slight_smile: