nPM1300: Fuel gauge

The Fuel gauge sample demonstrates how to calculate the battery state of charge using the nRF Fuel Gauge library.

Requirements

The sample supports the following development kit:

Hardware platforms

PCA

Board name

Build target

nRF52 DK

PCA10040

nrf52dk_nrf52832

nrf52dk_nrf52832

The sample also requires an nPM1300 EK.

Overview

This sample allows to calculate the state of charge, time to empty and time to full information from a battery connected to the nPM1300 PMIC.

Wiring

  1. Connect the TWI interface between the chosen DK and the nPM1300 EK as in the following table:

    nPM1300 EK connections.

    nPM1300 EK pins

    nRF52 DK pins

    SDA

    P0.26

    SCL

    P0.27

    GND

    GND

  2. Make the following connections on the nPM1300 EK:

    • Connect a USB power supply to the J3 connector.

    • Connect a suitable battery to the J2 connector.

    • On the P18 pin header, connect VOUT2 and VDDIO pins with a jumper.

    • On the P2 pin header, connect VBAT and VBATIN pins with a jumper.

    • On the P17 pin header, connect all LEDs with jumpers.

    • On the P13 pin header, connect RSET1 and VSET1 pins with a jumper.

    • On the P14 pin header, connect RSET2 and VSET2 pins with a jumper.

Building and running

This sample can be found under samples/npm1300_fuel_gauge in the nRF Connect SDK folder structure.

To build the sample with Visual Studio Code, follow the steps listed on the How to build an application page in the nRF Connect for VS Code extension documentation. See Building and programming an application for other building and programming scenarios and Testing and debugging an application for general information about testing and debugging in the nRF Connect SDK.

Testing

After programming the sample to your development kit, complete the following steps to test it:

  1. Connect the kit to the computer using a USB cable. The kit is assigned a COM port (Windows) or ttyACM device (Linux), which is visible in the Device Manager.

  2. Connect to the kit with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.

If the initialization was successful, the terminal displays the following message with status information:

PMIC device ok
V: 4.101, I: 0.000, T: 23.06, SoC: 93.09, TTE: nan, TTF: nan

Symbol

Description

Units

V

Battery voltage

Volts

I

Current

Amps (negative for charge, positive for discharge)

T

Temperature

Degrees C

SoC

State of Charge

Percent

TTE

Time to Empty

Seconds (may be NaN)

TTF

Time to Full

Seconds (may be NaN)

Dependencies

The sample uses the following sdk-nrfxlib library:

In addition, it uses the following Zephyr libraries: