Program uploading issue in ESP32-S3 in custom 4 layer PCB

[hardik1975]

I am working on a PCB design based on the ESP32-S3. In our initial prototype, we used a 2-layer PCB, and it worked fine.

For the next iteration, we upgraded to a 4-layer PCB, where we added additional Power and GND planes. However, we're experiencing issues when uploading code to the device.

Could the problem be related to using the same capacitor and resistor values in the RC circuits on the Enable pin and IO0 pin that we used for the 2-layer PCB?

Please advise on how we can address this issue. I am sharing the schematic below.

[ESP_Sprite]

Can you expand a bit on what issues you're experiencing specifically? (Also, note the S3 has integrated USB; you can generally get away entirely without the USB-serial converter.)

Also, you may need to increase C4 a fair bit, to e.g. 100nF or 1uF. It forms a power-on reset circuit with R4, and it also plays a role in the auto-reset dance.