ESP8266 Community Forum

- Sat Nov 10, 2018 6:28 am #79081 HI!
in my project i need to power an esp12 with 18650 battery.
I've tried with mcp1700 3.3v with 1uF caps (Vin-GND, Vout-GND)
with this setting the esp doesn't power up, so i've tried with 100uF cap before mcp1700 and 1000uF after,and a 1uF between VCC and GND on esp12 Module.

in my setup i have:
18650 battery (LG HG2 3000mah 20A)
mcp 1700 3.3v to92
24lc64 i2c eeprom
and ds18b20 sensor

If I try with external powerr supply everything goes ok, but with battery esp run my code only in RF_DISABLED mode.

what i'm making wrong?
in attachments my schema and my pcb. ( the resitors are all 10k except the pullup for ds18b20 )

thanks
jacopo

- Sat Nov 10, 2018 1:43 pm #79082 The MCP1700 does not have enough current capability. It can't handle the worst case surge the ESP8266 causes. I had wanted to use these but they were not reliable enough even with a 5 volt input supply.

I have soldered two in parallel and it has been able to power a lipo project of mine. What I did was file the top of the MCP1700 soldered to the pcb. I then soldered the second MCP1700 to the top of the first.

Since that project I have been using the HT7833 with a 500mA rating.

- Sat Nov 10, 2018 5:04 pm #79083 Error

Last edited by Giacopong on Sun Nov 11, 2018 3:31 am, edited 1 time in total.

- Sat Nov 10, 2018 7:07 pm #79084 Thanks for the reply! I see the mcp1825 with 500ma rating and I'm trying it.
Have you got some tips about the caps? With ht7833 what caps are you using?

Thanks
Jacopo