Failed to connect to ESP32-C3: Serial data stream stopped: Possible serial noise or corruption

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1

I designed a custom PCB using an ESP32 C3 module. After soldering everything on the board, I plugged it in to upload some test code, but it won’t upload anything. My computer detects the board. No matter what I’ve tried it gives this error: Serial port COM11: Connecting...................................... A fatal error occurred: Failed to connect to ESP32-C3: Serial data stream stopped: Possible serial noise or corruption. For troubleshooting steps visit: Troubleshooting - ESP32 - — esptool latest documentation Failed uploading: uploading error: exit status 2.

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This is the full schematic of the microcontroller part of the board. The transistors are disconnecting, so I am using manual booting via the buttons to try to boot the chip. GPIO 8 and 9 and 2 and EN are all pulled high, and the buttons pull pins 9 and EN low when pressed. I checked for shorts and there aren’t any, and I checked the voltages and they are correct. I am unable to check the ESP32 pins because they are pads underneath the chip and are unreachable.

I tried replacing the ESP32 chip and it still doesn’t work. The cable works to upload code to other boards, so it isn’t the issue.

I’ve been searching online for hours and nothing has worked. Does anyone know what could be the issue?

2

I see you did not follow any of the manufacturer’s recommendations on proper decoupling for the CP2102. That could be an issue.
Are D3 and D4 appropriate for USB?
Are USB_DP/N routed as a 90Ω differential pair?
Connecting the USB shield directly to ground is not recommended. Either leave it disconnected or use a parallel resistor and cap to ground.
You have VBUS connected through a diode directly to the output of an unpowered 5V regulator.

D2 is backwards!
There could also be layout issues.

3

I followed all of the recommendations from the ESP32 C3 datasheet, and I followed the provided schematics almost exactly. D3 and D4 are good, and I have a brother that used the exact ones and they worked. The DP and DN are a 90 ohm differential pair. The 5V regulator will be powered externally, but I haven’t connected that power yet. On the ESP32 C3 datasheet schematic, D2 is an ESD protection diode to gnd.

4

When powered by a power supply, it is only drawing around 7mA, so the ESP32 must not be turning on. I connected 3.3V directly to the 3.3V line and still only around 7mA. The pads are underneath, so I’m not sure how I could test if they’re soldered properly. I’ve swapped the ESP32 chip already and it didn’t fix it.