nPM13xx EK

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Overview

This sample is provided for evaluation of nPM1300 EK and nPM1304 EK. The sample demonstrates use of Dynamic Voltage Scaling (DVS) regulator API feature which allows to switch between chosen voltage levels or regulator modes by toggling configured GPIOs with a single regulator API call.

It also provides a shell interface to support the features of the nPM1300 and nPM1304 PMICs, including:

  • Regulators (BUCK1/2, LDO1/2)

  • GPIO

Requirements

The shield needs to be wired to a host board featuring the Arduino I2C connector. PMIC’s GPIO3 acts as an interrupt output, pins GPIO1 and GPIO2 are configured to control regulator modes (controlled by the MCU software through DVS).

In addition, PMIC’s VDDIO pin should be connected to an appropriate voltage reference.

E.g. for an nRF52 Series DK the wiring is as follows:

nPM13xx EK pins

SDA

SCL

GPIO1

GPIO2

GPIO3

VDDIO

GND

nRF52 DK pins

P0.26

P0.27

P0.17

P0.18

P0.22

VDD

GND

Building and Running

The sample is designed so that it can run on any platform (references to host GPIOs connected to the nPM13xx EK need to be updated in the npm13xx.overlay files to reflect chosen HW).

For example, when building for the nRF52 DK and the nPM1300 EK, the following command can be used:

west build -b nrf52dk/nrf52832 --shield npm1300_ek samples/shields/npm13xx_ek

Testing

After flashing the sample FW, you need to connect to the shell interface, where in case of successful initialization you will see the nPM13xx PMIC status messages containing charger status and battery voltage, current and temperature. Pressing and releasing the SHPHLD button on the EK will generate interrupts and these events will also be printed in the shell.

Pressing a dedicated button on the host DK (Button 1 on an nRF52 Series DK) will cycle DVS states.

DVS state (GPIO1 | GPIO2 level)

BUCK2 mode

LDO1 mode

LDO2 mode

0 (HIGH | HIGH)

OFF

OFF

OFF

1 (LOW | HIGH)

ON retention

OFF

OFF

2 (HIGH | LOW)

OFF

ON

ON

3 (LOW | LOW)

ON PWM

ON

ON

Note

On an nRF52 Series DK, DVS pins are also used for the onboard LED1 and LED2, so you can observe the DVS state pins visually: an LED lights up when the respective pin is LOW

Regulators

The regulator shell interface provides several subcommand to test the regulators embedded in the PMIC. Below you can find some command examples.

# list all the supported voltages by BUCK1
uart:~$ regulator vlist BUCK1
1.000 V
1.100 V
...

# enable BUCK2
uart:~$ regulator enable BUCK2
# disable BUCK2
uart:~$ regulator disable BUCK2

# set BUCK2 voltage to exactly 2V
uart:~$ regulator vset BUCK2 2V
# obtain the actual BUCK1 configured voltage
uart:~$ regulator vget BUCK1
1.800 V
# set BUCK1 voltage to a value between 2.35V and 2.45V
uart:~$ regulator set BUCK1 2.35V 2.45V
# obtain the actual BUCK1 configured voltage
uart:~$ regulator get BUCK1
2.400 V