ncs3.1.1 peripheral_uart sample could see the current spikes while in low power state between two advertising current curve

[OPQ]

Hi,

in ncs3.1.1 peripheral_uart sample after disable the uart init and gpio_config, the nrf54l05 can achieve the low power state,but the avg Idle current was about 5uA,seens little bit higher than nrf52.

Than I double check the power cumsumption curve, I could see the current spikes while in low power state between two advertising current curve as below:

The advertise interval was 300ms,the abnormal spike interval was about 130ms(seens not a fixed value), and I check and sure that these abnormal spikes were not the RC clock's calculate event. I can found the  RC clock's calculate event interval was 8sec at other where.

[Kazi Afroza Sultana]

Hello,

Are you running the sample on DK or your custom board?

How have you set your ppk configuration?

I can not open the screenshot you uploaded here, can you please upload this again?

[OPQ]

upload again,please refer.

Testing on my custom board(it's simple nrf54 module without any other ICs).

Not testing with PPK but with my DC current analyzer.

Other info:

1、These spikes peak is about 4mA;

2、After I change the adverting interval to a more larger value,like a 2000ms,there abnormal spikes were disapear.

[Kazi Afroza Sultana]

Hello,

I have looked at the screenshot of current measurement. Your average sleep current is almost in range. According to specification, for system on with RAM retention the average sleep current is about 2.9uA. The reason of irregular spikes is probably related to enabling any unused peripheral, you are right that it is not for RC clock.  

''、After I change the adverting interval to a more larger value,like a 2000ms,there abnormal spikes were disapear.''

It seems spike may be related to Bluetooth.

When you increase the advertising interval (e.g., to 2000 ms), the device spends much more time in low-power idle mode, and the spikes become infrequent. 

Can you please upload your application file so I can lool at code and other configuration?

[OPQ]

peripheral_uart_nrf54l05_lpw.zipHi, please find the uploaded applications file.

[Kazi Afroza Sultana]

Hello,

I have run your code and reproduced the issue. There are some warnings for unused variable and function in the code. But application run and flashed on the nRF54L15 dk successfully.

There is a spike after every radio activity and the distance between the spike and the radio start is 2.612 second and the spike current is 4mA (approx). But the average sleep current is high. I need to investigate this more. 

''After I change the adverting interval to a larger value,like a 2000ms, there abnormal spikes were disappear.'' 

I have increased the advertising interval to 5250 ms and observed no spike

	/* 5250 ms -> 5200 / 0.625 = 8400 (单位为 0.625 ms) */
	struct bt_le_adv_param adv_param = {
		.options = BT_LE_ADV_OPT_CONNECTABLE,
		.interval_min = 8400,
		.interval_max = 8400,
	};

 

I have asked our expert to look at the issue of seeing spike when advertising interval is not so large. 

Thanks.

BR

Kazi