How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Thu, 23 Jan 2025 08:22:24 GMT

Thank you. That's good to know.

To summarize up:

The simplest way to achieve System ON Idle is to use Hello World sample, built with CONFIG_SERIAL=n
Measurement is affected by Errata 31. It is presented on some devices and will be fixed in the next NCS release after v2.9.0

Shall we close this ticket then? Ah I saw you have closed the ticket. Many thanks.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Thu, 23 Jan 2025 04:06:48 GMT

It can work normally now

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Wed, 22 Jan 2025 11:47:56 GMT

Yes and no. west update will synchronize the SDK to what is defined in nrf/west.yml, so simply runs it won't change anything, unless you replace the entire west.yml with what is on main.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Wed, 22 Jan 2025 10:17:41 GMT

Can I use 'west update' directly? It's currently version 2.8.0

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Tue, 21 Jan 2025 12:18:52 GMT

I was tipped that this might be Errata 31 at play. There might be little peaks due to it.

The peaks are not milliamperes high like we see in the Power Profiler, but this compounds with a limitation of the PPK, where the voltage is measured in multiple level ranges, and if the actual level crosses between ranges, a false peak is generated.

Could you please try to install NCS at the main branch, and try again? A fix was made for it.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Tue, 21 Jan 2025 09:40:12 GMT

Oh, I mean, what does the Power Profiler app look like when you use Ampere Meter mode. And when you use Ampere Meter mode, you need to connect all three pins, VIN, VOUT, and GND.

What about substituting parts for the measurement? Is it possible for you?

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Tue, 21 Jan 2025 01:39:36 GMT

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Mon, 20 Jan 2025 11:38:29 GMT

I am trying to reproduce the issue on my end but haven't been able to yet. I only have earlier prototyping revisions of the DK, so I wonder if that is the difference. I will try to acquire a DK from the same revision as you.

Meanwhile, could you please share what it looks like when you measure in Ampere Meter mode? With all three wires connected, that is.

Do you also have a higher performance power analyzer, a different PPK, or a different nRF54L15 DK to switch up the setup? This is to help isolating where the problem is.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Mon, 20 Jan 2025 02:17:43 GMT

The two in the red box are both 3.43V.

The two in the red box are both 2.93V.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Sun, 19 Jan 2025 10:25:36 GMT

[quote user="666"]

Hieu said:
Beyond this, at 3.3V, you would have to zoom in and selectively measure between the spikes.

Is this the first two images? Is the power consumption 1.8uA at this time

[/quote]

No this also seems wrong.

Could you please measure VDDM and VDD_nRF with a voltmeter and let me know what the voltages are?

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Sat, 18 Jan 2025 12:05:59 GMT

[quote userid="9456" url="~/f/nordic-q-a/117590/how-to-test-the-power-consumption-of-system-on-idle-with-grtc-xosc-and-256-kb-ram/518603"] you can see that as supply voltage increase, current should decrease.[/quote]

From the graph, it appears to be limited to voltages below 3V?

[quote userid="9456" url="~/f/nordic-q-a/117590/how-to-test-the-power-consumption-of-system-on-idle-with-grtc-xosc-and-256-kb-ram/518603"]Beyond this, at 3.3V, you would have to zoom in and selectively measure between the spikes.[/quote]

Is this the first two images? Is the power consumption 1.8uA at this time

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Thu, 16 Jan 2025 11:05:12 GMT

The issues here are the spikes that you see all over the graph. They are not true spikes but rather false measurements due to limitations of the PPK.

I don't always see this issue, but when I do, changing the voltage in small steps help me find a threshold where such spikes occur. That doesn't help you see the real current draw at 3.3V, but the idea is, you can see that as supply voltage increase, current should decrease. Beyond this, at 3.3V, you would have to zoom in and selectively measure between the spikes.

I am asking internally what those spikes are and what can be done about them. I will get back to you once I get anything.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Wed, 15 Jan 2025 09:20:42 GMT

The following is the same demo, showing the situation by changing the voltage

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Wed, 15 Jan 2025 08:42:32 GMT

That does not make sense at all. The current at 1.8V should be lower than the current at 3.3V, assuming the same operation state.

Are you absolutely sure?

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Wed, 15 Jan 2025 01:11:14 GMT

When DK runs at 1.8V, it is normal (3uA).

Why is there 6uA at 3.3V?

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Mon, 13 Jan 2025 14:59:41 GMT

The light you pictured is the debugger and shouldn't affect the board.

Do you know what VDD you are using? The datasheet lists current consumption at 3.3V. The DK runs 1.8V by default.

You can try to connect only GND and VOUT from the PPK and run it in source meter mode.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Mon, 13 Jan 2025 08:55:21 GMT

Could the light in the above picture be the factor causing the 3uA power consumption difference

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Fri, 10 Jan 2025 07:36:18 GMT

[quote userid="9456" url="~/f/nordic-q-a/117590/how-to-test-the-power-consumption-of-system-on-idle-with-grtc-xosc-and-256-kb-ram/517858"]Is this the hello_world sample running without UART?[/quote]

Yes,no UART.

Only one light in the red box.

There are currently no other boards available.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Fri, 10 Jan 2025 07:27:18 GMT

Hi 666,

Is this the hello_world sample running without UART?

Is any LED on at all?

Do you have a different board to test this with?

Could you please share the information on the white square label on your DK board?

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Fri, 10 Jan 2025 01:34:16 GMT

Hi,

This still has 6uA, which does not match the 3uA specified in the specifications.

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Hieu — Thu, 09 Jan 2025 21:22:38 GMT

Hi 666,

My apology. The blinky sample was my idea. I thought wrongly that since it doesn't enable UART, it won't have UART and can show the performance clearly. I was wrong. UART is enabled by default, and you need to disable it.

So, if you rebuilt the sample with CONFIG_SERIAL=n, you will see better number.

The reason I recommended blinky is to also point out that the measurement will also shows current drawn by the LED circuit.

If you want to observe just the nRF54L15 in System ON Idle, you can also use hello_world, with CONFIG_SERIAL=n.

Hieu

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Wed, 08 Jan 2025 02:12:20 GMT

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

Sigurd Hellesvik — Tue, 07 Jan 2025 13:17:11 GMT

Hi,

Can you try to measure the same for the blinky sample and let us know what current draw that has (when the LED is off in the blink cycle)?

Regards,
Sigurd Hellesvik

RE: How to test the power consumption of "System ON IDLE with GRTC (XOSC) and 256 KB RAM"

666 — Mon, 06 Jan 2025 07:47:51 GMT

HI ALL,

Do you have any suggestions？