Logaritmicly decreasing sensor readings with low power on ESP32-C3-13

[ogedik]

Hi,

I am working on a capacitive sensor attached to ESP32 circuit and reading humidity value through GPIO0 pins. Circuit has supplied by 3.7V 2500 mAh LiPO battery. There's no problematic readings with between 4.0v to 3.5v. Problem began after 3.5v level. After this point on readings are decreasing by battery voltage level. For example I read 2900 on ADC GPIO0 when battery level at 3.7v. But readings have decreasing 2500 when battery level around 3.3v level. In short after 3.5v level on battery, sensor readings are decreasing logarithmic by battery voltage level.

To find a solution this problem; I attached a 3v booster on Vcc capacitive sensor, but not solve it.

Is there any way to solve to keep sensor readings stable on low voltage levels? Please find circuit diagram below;

Thank you for your helps.

Orkun Gedik

[thezcx]

Gpio0 usually a strapping pin don't use it try another one.
If you need accuracy you can use ads1115 for adc reading which will not be effected by voltage.
Or, you can use Battery 18650 Stats library to read it more accurately.

Ya da hocam 5vtan düş en temizi