Electron E series - LiPo terminal voltage limitations

Hardware
1

Hi,

I’m close to finishing my prototype board using the electron E-series and I have a question regarding the input voltage.

The application is entirely battery powered with no rechargeable function. I’m planning to use 3xAAA batteries(~3000mAh) to power the electron and swap out the batteries when needed. Nominally 3x in series will give ~5.0volts, drops over time.

Now, the datasheet specifies that the LiPo terminal is the most efficient way to power the module but has a 3.6v~4.4V. Will it tolerate the 5.0V or am I forced to use the VIN terminal in this case.

Cheers

2

The value is based on the bq24195 PMIC. According to the datasheet, the recommended maximum input voltage on VBAT is 4.4V. The absolute maximum rating is 6.0V.

In my opinion, 5.0V is too high above 4.4V to be safe and you should use VIN.

If you do use the LiPo connector, make sure you disable charging and the charge safety timer.

1 Like
3

Brilliant! Thanks for the quick reply.

To clarify your last point, I’m assuming API’s are available to disable both the features?

Best

4

I think you want to look here: https://docs.particle.io/reference/device-os/firmware/electron/#charge-timer-control-reg

and here: https://docs.particle.io/reference/device-os/firmware/electron/#charge-timer-control-reg

5

The full code is here, but omit the line to disable the BATFET. You need to leave the BATFET enabled, otherwise you can't power from the LiPo battery connector. The other lines of code will prevent charging and prevent the LED from flickering or blinking.