Module with nRF54L05 + nPM2100 has 87uA idle current

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

Kenneth — Wed, 02 Sep 2026 07:16:37 GMT

Hi,

Honestly I can't fint what is wrong here, I suspect either some issue with the schematic, layout and/or some leakage current by some component on the module. Maybe modify one of the modules to see if you can remove components, even bypassing the nPM2100 for test.

Kenneth

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

hsmptg — Tue, 01 Sep 2026 18:14:38 GMT

Sorry to insist, but could someone give me some advice on how to solve this problem?

As I said, even with the functionality working as expected, this idle current level makes it impossible to use my modules in real situations.

Regards,

Hélio

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

hsmptg — Mon, 31 Aug 2026 16:35:44 GMT

P1.11 and P1.12 are the I2C links to the nPM2100 (each has a 10k pull-up resistor). I think my custom board .dts has that defined.

I admit that I also have P1.04 and P1.05 connected directly to GPIO1 and PG/RESET of the nPM2100 (which are not defined in my .dts since I do not use them). I already tried to fix these potential "floating pin" issues using some AI advice in my .dts (I am not an expert on device trees), but nothing changed.

Here are some excerpts of a new .dts file that I tried to define those pins, but the idle current remains the same! 😞

...

/*
 * I2C22 (PERI domain: SCL = P1.11, SDA = P1.12) -> nPM2100 PMIC.
 * Configuration mirrors the nRF54L15 DK overlay already validated on this
 * firmware.
 */
&i2c22 {
	status = "okay";
	compatible = "nordic,nrf-twim";
	clock-frequency = <I2C_BITRATE_STANDARD>;
	pinctrl-0 = <&i2c22_default>;
	pinctrl-1 = <&i2c22_sleep>;
	pinctrl-names = "default", "sleep";

	npm2100_pmic: pmic@74 {
		compatible = "nordic,npm2100";
		reg = <0x74>;
		status = "okay";

		/* SHPHLD button behaviour: hold >2s to enter ship mode */
		shiphold-longpress = "ship";

		npm2100_gpio: gpio-controller {
			compatible = "nordic,npm2100-gpio";
			gpio-controller;
			#gpio-cells = <2>;
			ngpios = <2>;
		};

		npm2100_wdt: watchdog {
			compatible = "nordic,npm2100-wdt";
		};

		npm2100_regulators: regulators {
			compatible = "nordic,npm2100-regulator";

			npm2100_boost: BOOST {
				regulator-always-on;
				regulator-min-microvolt = <1800000>;
				regulator-max-microvolt = <3300000>;
				regulator-init-microvolt = <3000000>;
			};
		};
	};
};

/*
 * UART30 (LP domain: TXD = P0.00, RXD = P0.01).
 * Debug/logging is done over RTT, so this UART is defined but left unused
 * by the console/shell -- available for an external host or peripheral link.
 */
&uart30 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart30_default>;
	pinctrl-1 = <&uart30_sleep>;
	pinctrl-names = "default", "sleep";
};

...

&gpio0 {
	status = "okay";
};

&gpio1 {
	status = "okay";

	/*
	 * Direct (non-I2C) control/status lines to the nPM2100 PMIC:
	 *   P1.04 -> nPM2100 GPIO1     (general-purpose PMIC pin)
	 *   P1.05 -> nPM2100 PG/RESET  (open-drain, active-low Power-Good /
	 *            host-reset pin)
	 * No driver claims either pin yet, so without an explicit config
	 * they'd sit in the SoC's reset state (Hi-Z input) and float.
	 * GPIO hogs apply a defined state at boot (CONFIG_GPIO_HOGS,
	 * auto-selected from this devicetree) before any application code
	 * runs. Revisit the direction/pull once the actual usage (e.g.
	 * PMIC interrupt on GPIO1, or driving PG/RESET low to force a PMIC
	 * reset) is implemented -- these defaults only guarantee a safe,
	 * defined idle level.
	 */
	npm2100_gpio1_hog: npm2100-gpio1-hog {
		gpio-hog;
		gpios = <4 (GPIO_ACTIVE_HIGH | GPIO_PULL_DOWN)>;
		input;
		line-name = "npm2100-gpio1";
	};

	npm2100_pg_reset_hog: npm2100-pg-reset-hog {
		gpio-hog;
		gpios = <5 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
		input;
		line-name = "npm2100-pg-reset";
	};
};

...

Regards,

Helio

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

Kenneth — Mon, 31 Aug 2026 15:16:25 GMT

Hello,

It seems P1.11 and P1.12 are configured in your HW. Likely caused by twi22/uart22/spim22 is not disabled in the devicetree, I would start looking in devicetree to check if any of those are enabled, and then disable them. Likely the pins are floating.

Kenneth

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

hsmptg — Mon, 31 Aug 2026 14:30:06 GMT

Dear Kenneth

Here are the files you asked for:

devzone.nordicsemi.com/.../myHW.txt devzone.nordicsemi.com/.../DK.txt

Here are the idle currents measured by the PPK2 in both cases:

Many thanks for your help!

Helio

RE: Module with nRF54L05 + nPM2100 has 87uA idle current

Kenneth — Mon, 31 Aug 2026 12:36:13 GMT

Hello

I am attaching a python script you can try to run, this will dump all register content of the nrf54l05. You can run run the script for the DK and on your own hardware, then we can compare the two to try to narrow down the possible difference.

You can read out by running: python .\read_global_registers.py --all

To store the output to a file you can call: python .\read_global_registers.py --all > your_hardware1.txt

Do the same for your hardware and the DK with the above code you shared.

Kenneth

devzone.nordicsemi.com/.../nrf54l05_5F00_application.zip