Power consumption of TTGO T8 Board

[ThomasChr]

Blowing the power IC off was a success. I'm down to 100 µA.
Any suggestions what I can try next? The ESP32 should go down to about 10 µA, so there must be still something which is drawing a tiny bit of power...

[mattyt]

I can confirm that the TinyPICO can get down to 10-20uA in deep sleep. Next up I'd suggest having a look at any pull up/down connected to any ESP32 GPIO...

[ThomasChr]

Hi matty,

thats exactly why I ordered some of those TinyPICOs

Cheap chinese development boards haven't got poer efficency in mind!

I'll try blowing of some resistores and will post the outcome here.

[ThomasChr]

I just blowed some resistors of the board and this is the outcome:

Without voltage regulator (providing 3.3V directly on the rail): 100 µA
Without the Voltage Divider from the Power IC: 90 µA
Without the pullups for the SD Card IO Lines: 5 µA

So I think I'm pretty much done

[Roberthh]

What is left that works?

[ThomasChr]

Not much

The ESP32 still works fine, but without a power IC you need to power the 3.3V rail directly. Which is not that bad because it accepts between 2.3V and 3.6V. The USB2serial Chip is gone, so no USB anymore. And after removing the pullups for the SD Card I'm not quite sure if the SD Card will still work. But you've got flash and psram, and also the Wifi and Bluetooth stuff. So not bad for 5µA deepsleep power.

But it would surely be easier to just by a ESP32-Wrover module

Thomas