-->
Page 1 of 2

Is my ESP-12F Module dead?

PostPosted: Tue Sep 13, 2016 5:13 pm
by buchacho
I have been trying to figure out power issues with my module. I had been running it on 3x AA Ni-MH batteries at about 3.6V and I was trying to use a new DC-DC converter with current limiting attached to a wall-wart supply.

On the DC-DC converter, the board was having trouble booting unless I set the voltage to somewhere around 3.7V. At 3.3V it was not turning on. I had current limited to 800mA. Sometimes the module would just keep blinking the blue LED with a high current draw of around 700mA. One time I caught on the serial port a exception/stack dump, so it booted but couldn't get through my program.

But now when I hook it up to power and it doesn't do anything and draws around 7-800mA. I don't even have CH_PD pulled high and it does this. I don't think I ever really powered it above 3.6V (measured at the input) since I have been using it. Is it dead or can I revive it somehow?

Re: Is my ESP-12F Module dead?

PostPosted: Tue Sep 13, 2016 6:24 pm
by Barnabybear
Hi, I'm guessing it's not dead just not liking the new power. Have you tried batteries again?
The bit that caught my attention in your post was "with current limit", the ESP when switching between 'normal' and 'WiFi' has a big demand on the power supply.
OK it only changes between 85 mA and 230mA, but it is instant. It's a bit like driving down the road and coming across a hill you didn't expect, if you don't change down a gear quick enough the engine will stall. If your new supply can’t react fast enough to the new current draw the voltage will drop and the ESP will reset. It then boots up (85mA) and tries to connect to WiFi (230mA). This just keeps going round in a 325mS reset loop.
The voltage shouldn’t be an issue, unless your new regulator is from a higher voltage (12V) and is not working correctly.
Can you link where you purchased your supply from please – if it is constant current as opposed to constant voltage it could have damaged your ESP.

Re: Is my ESP-12F Module dead?

PostPosted: Tue Sep 13, 2016 8:38 pm
by buchacho
Yeah, I did try batteries again, but it wouldn't respond to reset or anything / no blue LED flash, and it draws a lot of current. The supply is like this: https://www.amazon.com/DROK-Numerical-R ... 01CE5P33M/ It's more like a current limit where you set the voltage.

I went back to using another module and it was working perfectly at 3.3V. Then I tried the new supply and now it is acting strange, needing higher voltage. I am wondering if you can zap the chip in a way that it still works, but is somewhat intermittent after being damaged.

Re: Is my ESP-12F Module dead?

PostPosted: Thu Sep 15, 2016 7:49 am
by rudy
Yes these can be damage and appear to still work. The problem will be that you never know when you will get unreliable operation.