Estimating current consumption of NRF54L15

RE: Estimating current consumption of NRF54L15

Vidar Berg — Thu, 19 Feb 2026 06:31:36 GMT

Hi, it is the Bluetooth SW stack requires that the CPU to run at 128 MHz:

[quote userid="4240" url="~/f/nordic-q-a/127059/estimating-current-consumption-of-nrf54l15/561436"]The CPU can technically be configured to run at 64 MHz, but bluetooth is only tested and qualified at the default 128 MHz frequency. In other words, 64 MHz is not supported.[/quote]

There is no relation between the CPU frequency and the radio frequency. How the 2.4 GHz signal is generated from the crystal oscillator is also not included in the documentation.

RE: Estimating current consumption of NRF54L15

Ashokrajpilli — Thu, 19 Feb 2026 06:00:04 GMT

Thanks Vidar, Now I understand you are referring to only 128 MHz that is run for bluetooth/radio. Apologies for the confusion created. I had a trouble understanding the clock tree how the processor clock, bluetooth clock is related,
I am with an understanding that processor clock is different, bluetooth/RF clock is different.

can Processor clock run at different frequency other than bluetooth clock?
if yes, can you point out in the datasheet/any nordic hyper link so that i can get high level understanding.

RE: Estimating current consumption of NRF54L15

Vidar Berg — Wed, 18 Feb 2026 09:05:40 GMT

As mentioned earlier, those frequencies are not supported. That is also why no measurements are provided.

RE: Estimating current consumption of NRF54L15

Ashokrajpilli — Wed, 18 Feb 2026 08:54:51 GMT

I need a formula vidar because i need to calculate for 64 MHz, 16 MHz and decide what is the preferred frequency for my application as it impact current consumption.

RE: Estimating current consumption of NRF54L15

Vidar Berg — Wed, 18 Feb 2026 08:50:42 GMT

It is using 128 MHz and this is the only supported frequency.

RE: Estimating current consumption of NRF54L15

Ashokrajpilli — Wed, 18 Feb 2026 08:49:51 GMT

At what frequency nordic power profiler is considering? for bluetooth and processor ?

RE: Estimating current consumption of NRF54L15

Vidar Berg — Wed, 18 Feb 2026 08:45:05 GMT

Hi,

The CPU can technically be configured to run at 64 MHz, but bluetooth is only tested and qualified at the default 128 MHz frequency. In other words, 64 MHz is not supported.

RE: Estimating current consumption of NRF54L15

Ashokrajpilli — Wed, 18 Feb 2026 08:36:58 GMT

Hi Vidar,

There is typo in my sentence above i.e., instead of nordic power profile i have kept nordic powerful. I am aware of profiler but my question is not related to TX power/advertisement payload, how did the tool estimates the current consumption without considering the clock frequency? Need indetail information.

RE: Estimating current consumption of NRF54L15

Vidar Berg — Wed, 18 Feb 2026 07:48:10 GMT

Hello,

Please have a look at our online power profiler here: https://devzone.nordicsemi.com/power/w/opp/2/online-power-profiler-for-bluetooth-le. It allows you to estimate the expected current consumption for various configuration parameters such as TX power and advertisement payload.

Best regards,

Vidar