I have a 3S LiIon battery pack, so ~12V, connected to an MPM3610 buck converter to produce 5V for an ESP32S3 DevKit C-1. I need to also have a USB cable (with 5V) attached to the ESP32S3 for programming. Is this circuit adequate for having the 5V from the battery connected to the ESP32S3 AND the USB cable attached to the ESP32S3? The battery should provide all the 5V for the components on the board that need 5V. The USB 5V is just an unused feature of the USB connection for programming and serial terminal.

The reason I ask, is I have 2 flavors of boards (A and B), each with the identical circuits as shown here for the battery/MPM3610/ESP32S3. I was working with one of the A boards programming the ESP32S, so both USB and battery connected, and the MPM3610 does not product 5V with or without the USB cable attached. I did not test it before I plugged in the cable. I tried one of the B boards and just plugged in the battery, and the 5V is working. I don't want to plug in the USB cable to program the ESP32S3 on the B board until I am sure I am not going to blow out the MPM3610. Since the circuits on the two boards are identical, I think they should work on bot boards.

I powered on another type A board without attaching the USB cable to the processor, and the MPM3610 worked and produced 5V. I am more confident that the MPM3610 circuit is working, as it produced 5V from 12V battery input without ever attaching the USB 5V to the board. How did I blow up the MPM3610 on the first type A board I brought up and programmed with the USB cable attached? I have attached my MPM3610 schematic. BTW, the boards were made by JLCPCB.

 

I do not see the "Common" side anywhere, and without the common you have no circuit, only some connections. And quite likely these items also need to communicate, and so commons also need to be connected. If all of the 5 volt sources are stable then I don't see a problem. BUT the commons do need to be connected deliberately, not just "sort of connected".

 

The USB 5V is just an unused feature of the USB connection for programming and serial terminal.

I think that 5 volt module might have been already defective.
Don't really see how the 5V USP supply should damage anything.
If in doubt remove diode D9 from the circuit or cut the trace to either side of the diode.

 

I do not see the "Common" side anywhere, and without the common you have no circuit, only some connections. And quite likely these items also need to communicate, and so commons also need to be connected. If all of the 5 volt sources are stable then I don't see a problem. BUT the commons do need to be connected deliberately, not just "sort of connected".

I don't understand your comment. All the grounds are tied together. This circuit works on 4 other boards. Just one of them has the 5V failure.

 

I think that 5 volt module might have been already defective.
Don't really see how the 5V USP supply should damage anything.
If in doubt remove diode D9 from the circuit or cut the trace to either side of the diode.

Or, the MPM3610 was defective. I cannot cut D9 as I have no idea where it is among all the tiny SMB parts on the DevKitC board. 4 other identical boards powered on without any 5V issues, so I think this board has a bad part.

 

Since four other boards worked initially, it may well be that a manufacturing defect, such as a small solder splash short circuit is the problem. That would suggest a very close inspection, probably with a bright light and a good magnifier.