ESP8266 Community Forum

- Sun Aug 09, 2015 12:20 pm #25461 Hello,

I am trying to use an AMS1117 (already built, ready to be used) to power an ESP-01:
http://www.aliexpress.com/item/High-Qua ... 41751.html

Thing is, I can't find out if the problem is coming from the power source, the AMS module or the ESP-01.
When booting, it is displaying garbage, followed by few identical lines saying:

Fatal exception (0):
epc1=0x4021c341, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000

Is there an obvious issue with this setup that is coming to anyone's mind ?

Thank you

- Mon Aug 10, 2015 1:29 am #25507 Right off the bat i would suggest to try adding one bigger capacitor to the 3.3V line and see, if it fixes the issue. If it does, then obviously a capacitor is needed as the module you are using can't handle the big changes in current the ESP produces.

- Mon Aug 10, 2015 5:28 am #25513 As a side note, I flashed a given firmware and read it back from the ESP and there's no difference between the two of them.

Any value in mind regarding the capacitor to try between vout and ground ?

- Mon Aug 10, 2015 5:35 am #25514

As a side note, I flashed a given firmware and read it back from the ESP and there's no difference between the two of them.

Any value in mind regarding the capacitor to try between vout and ground ?

The bigger, the better. I had some 470uF ones laying around and with my rc wifi car, i put one on my 7.4V raw power line (2x18650 li-ion batteries) and one on 3.3V power line between buck converter and ESP.

Possibly it's a bit overkill, but capacitors don't cost anything...