Measuring the board current consumption

leo_lau_racefit

Hello, I’m trying to measure the current consumption on the SparkFun Thing Plus nRF9160.
There is a current measurement pin on nRF9160DK which I can connect a PPK2. Is there any pins or testing pads I can do the similar?
Any suggestions is greatly appreciated.

jaredwolff

leo_lau_racefit the best sample, right now, is the active-sleep sample in the 1.7.x branch of NFED: https://github.com/circuitdojo/nrf9160-feather-examples-and-drivers/tree/v1.7.x/samples/active_sleep. You’ll need to use NCS 1.7.x with this branch as I’ve seen different results with the same code across versions of NCS.

leo_lau_racefit

jaredwolff
Thank you for your reply.
I have tried the active-sleep sample and measured the current with a USB multimeter. Static current is about 45mA.
https://photos.app.goo.gl/Lq91Z3XHkDrAesH19
Another method I can think of to measure current consumption is connecting a multimeter in series with a battery to the board JST connector. Static current is about 6mA.
https://photos.app.goo.gl/noNDb4Bv6Sae531q7

To sum up, here is my connection in block diagram:
https://photos.app.goo.gl/3XkimqBKiz92HbZU9

Is these the suitable ways to measure current consumption? Or any alternative ways(like nRF PPK2)?

jaredwolff

leo_lau_racefit Is these the suitable ways to measure current consumption? Or any alternative ways(like nRF PPK2)?

You should be able to use something else like the nRF PPK2 as well. All depends on what you’re trying to characterize. Unfortunately the Thing Plus nRF9160 is not optimized for low power active sleep. (It is for low power shutdown + RTC though).

leo_lau_racefit

jaredwolff
Thank you for the quick response.

Unfortunately the Thing Plus nRF9160 is not optimized for low power active sleep.

May I ask which causes the high idle current consumption(firmware not optimized or the hardware components problems)?

jaredwolff

leo_lau_racefit it’s hardware related.

leo_lau_racefit

Thank you for the information.

jaredwolff

You got it!

Btw, the latest nRF9160 Feather has a much lower “active” sleep. <200µA and room for improvement. I just haven’t found the bit in firmware that needs to be flipped to reduce it more. 😇

Skalis

jaredwolff Hello , I did power measurement using active-sleep sample on Feather V3 with Otii tool , the floor current is arround 4.2mA, what could be the reason ?
I will do the same test next week with V4 , where can I found V4 schematics please ?
Thank you.

jaredwolff

@Skalis what version of the board do you have? Older versions unfortunately don’t have the best active sleep current.

See the attached.

https://community.jaredwolff.com/assets/files/2022-01-28/1643409856-626687-nrf91-feather-v4.pdf

Skalis

jaredwolff Thank you for the quick reply .
I think it’s the Feather V3 (In the pcb bottom side : BRD-0015-03 3/24/21).
Do you think with some FW GPIO adjustement I could acheive the some idle current as with V4 ?

jaredwolff

Skalis if you use the external RTC to shut everything down, yes. Otherwise, there’s not an easy fix unfortunately.