nPM1300 efficiency

RE: nPM1300 efficiency

Tomi Koskela — Fri, 13 Jun 2025 11:05:38 GMT

The VDDIO is also going to the nRF Controller and level shifters on the board, so we don't want to include that if we want to measure nPM1300 efficiency. The VDDIO quiescent current of nPM1300 itself is negligible

RE: nPM1300 efficiency

Nick_RA — Fri, 13 Jun 2025 10:19:19 GMT

Hi Thanks for the reply.

[quote userid="118467" url="~/f/nordic-q-a/122206/npm1300-efficiency/539154"]Also note that the VDDIO is powered by default by buck2 and that will increase the current consumption. You can supply the VDDIO with external 1.8V supply (connected to the P18 center pin) to remove this current consumption from the equation. [/quote]

OK, but that's a bit academic because from my reading of the PS, VDDIO is always required..?

[quote]VDDIO must be present in all operating modes of the chip, except in Ship and Hibernate modes.[/quote]

...so in a real-world product VDDIO is always part of the equation.

I'll re-test with the logging halted which should get a slightly more accurate result, then proceed from there.

RE: nPM1300 efficiency

Tomi Koskela — Fri, 13 Jun 2025 08:33:30 GMT

Hello, you can disable the polling with 'log halt' command in the terminal window. This will get rid of the 1s current spikes.

Also note that the VDDIO is powered by default by buck2 and that will increase the current consumption. You can supply the VDDIO with external 1.8V supply (connected to the P18 center pin) to remove this current consumption from the equation.

You can also disable buck1 to get the quiescent current down.

In no load condition, both bucks running you should be in 800nA quiescent current from VBAT.