I am currently testing a circuit with a ch340 and an esp32, to program it in USB with Arduino. The ch340 chip is not detected. I installed the CH341SER drivers and I can program other Arduino nano clones that have a CH340.



If anyone has any ideas on how to solve the problem or any comments on the schematic it would be great!

 

I am currently testing a circuit with a ch340 and an esp32, to program it in USB with Arduino. The ch340 chip is not detected. I installed the CH341SER drivers and I can program other Arduino nano clones that have a CH340.

View attachment 344951

If anyone has any ideas on how to solve the problem or any comments on the schematic it would be great!

Can you give us a legible schematic. Blurry white lines and text on a black background is horrible.

 

 

Where are your 0.1uf decoupling/bypass capacitors for the CH340 and other devices? The ESP32 has them on the module.

https://www.wch-ic.com/products/CH340.html



CH340C, CH340N, CH340K, CH340E, CH340X and CH340B have integrated clock, no external crystal required.
What part are you using?






This is showing a part that needs the xtal but the individual decoupling caps are still needed on each device.


https://cdn.sparkfun.com/datasheets/Dev/Arduino/Other/CH340DS1.PDF

When designing the PCB, pay much attention to some notes: decoupling capacitance C8 and C9 must keep near to connection pin of CH340; makes sure D+ and D- are parallel and supply ground net or pour copper beside them to decrease the disturbance from outside signal; the relevant signal between XI and XO must be kept as short as possible. In order to lessen the high frequency disturbance, play ground net or pour copper to the relative equipment.