Source Impedance matching using voltage divider for monitoring battery voltage.

[Hardik]

Hello All,

I am using NRF51822 controller in my design.

I want to monitor battery voltage using ADC pin with voltage divider.

I have LIPO battery with 3.7V and 200mAH rating.

Can you suggest how to match source impedance values and what can be maximum values of resistor that can be used to make resistor divider.

Suggest any reference circuit.

Also looking for option of FET with Voltage divider.What parameters are to be taken care.

Thanks

Hardik Rawal

[Jørgen Holmefjord]

Hi,

I would recommend that you take a look at the blog post "Measuring Lithium battery voltage with nRF51".

Best regards,
Jørgen

[Jørgen Holmefjord]

Yes, the capacitor helps with this. As you can see, the resistors in the blog post is much higher than 5k Ohm. Please have a look at this thread.