ESP8266 Community Forum

- Sat Dec 12, 2015 6:21 pm #36296 Hi all,

I'm developing a sensor/relay board that runs from a 3v3 supply. I'm trying control it from a LoLin that is running a small MQTT-client controller app written using the Arduino port.

I works fine when I debug it over USB, but it doesn't reliably boot up when powered from the boards supply. I've hooked up all the "3v" lines to my 3v3 supply, and all the "G" lines to my ground. What else do I have to do to get the board to operate stably? I don't have a 5v supply available that I could connect to VIN

Thanks!

Lisa

- Sat Dec 12, 2015 9:43 pm #36301 Does your 3v3 supply enough current? The ESP can draw about 300mA in bursts, if your power supply can't handle that it will brown out.

- Sun Dec 13, 2015 2:34 am #36307 Hi Lethe,

I'm using a VTX-214-005-103, which claims to be rated for 1.5A. Further experimentation seems to indicate it's only a problem on cold power up. If I power cycle the mains reasonably quickly, it seems to boot up ok. I'd left "Vin" floating so that connecting USB would still work, but I'm wondering if this was a mistake?

Thanks!