ESP8266 Community Forum

- Sat Apr 08, 2023 9:11 am #96211 Hi

I am inexperienced with any kind of microchips. I started week ago and during this time I have had some strange problems.

I am able to write program, upload it and run microchip. I am using the same USB UART converter every time (CH340G) but I have 3 power sources:

1. CH340G - if ESP is supplied from it I can flash ESP, but it doesn't run. When I change power source it run - so uploading works correctly.
2. HW-131 (breadboard power module) - I can not flash ESP. LED blink but at the end I get: Failed to connect to ESP8266: Invalid head of packet (0xFD). But(!) correctly flashed ESP can be run with this source of power.
3. Arduino UNO - I can flash and I can run chip - no problems.

Where is the problem?
Why one source of power is appropriate only for flashing and the other only for running?
Is there anything I can do to adapt CH340G or HW-131 to work in both "modes"?

- Mon Apr 10, 2023 3:23 am #96218 The 3.3V supply from the on-board regulator on a USB-Serial converter does not supply enough current to support normal operation of an ESP8266.

Although the average current of an ESP8266 during normal wifi operation is around 80mA, there can be peak current pulse demands of 400mA. It is normally recommended to use a power source of 500mA or higher,

It may work during programming as the wifi would be off, but I wouldn't recommend doing that as you don't want the programming to be unreliable.

One trick I use is to add a separate 3.3v regulator onto the back of the USB-serial module powered direct from the USB 5V supply. This avoids the need to have a separate power source.