power management

RE: power management

harrys — Wed, 30 Jun 2021 11:44:25 GMT

log is off . i want to know . commenting "log_init()" function is right way of doing nrf log off.

i have initialized adc. and then de_init adc.

with adc current = 5mA

with deinit adc = 200uA

is there any thing i did wrong.

RE: power management

Susheel Nuguru — Wed, 30 Jun 2021 11:33:56 GMT

200uA sounds reasonable when advertising. If you are measuring this after advertising stopped then it is a bit high.

Check if you have enabled some logging that keeps the serial device on which inturn keeps HFCLK high.

RE: power management

harrys — Wed, 30 Jun 2021 09:47:44 GMT

yes it takes around 200uA in sleep mode. is this can be issue of hf clk. if yes how i can disable it

RE: power management

harrys — Wed, 30 Jun 2021 09:04:37 GMT

you mean to say that beacon example is already working in system on sleep mode .

RE: power management

Susheel Nuguru — Wed, 30 Jun 2021 08:49:29 GMT

beacon is using nrf_pwr_mgmt. n the idle_State_handle, it calls nrf_pwr_mgmt_run() which in calls the system idle sleep functions. So you do not have to do anything as the beacon example is already doing the system of idle calls in idle mode in the for(;;) loop in the main function.

RE: power management

harrys — Wed, 30 Jun 2021 08:24:15 GMT

yes i have tested ble_uart_example in "system on sleep" mode on my hardware it takes around 15uA.

can you tell me steps to do the "system on sleep" mode in beacon example

RE: power management

Susheel Nuguru — Wed, 30 Jun 2021 08:18:24 GMT

OK, So you have made some changes that I have not tested.

Can you please first benchmark the changes you did on one nRF52 DK to see how much our DK. If it is about the same on the DK, then you have no issues on your custom hardware and then we can try to figure out the split in the power consumption that you are observing.

RE: power management

harrys — Wed, 30 Jun 2021 07:37:25 GMT

if you change the NON_CONNECTABLE_ADV_INTERVAL from 100ms to 500ms, you can see that the average power drops from 750uA to around 500uA.

my hardware is consuming 1mA current when no advertising. i want to run the "system on sleep"

so i enabled rtc interrupt and called _WFE in for(;;);

RE: power management

Susheel Nuguru — Wed, 30 Jun 2021 07:18:56 GMT

Hi,

Duration of advertisement will not influence the power consumption average while measuring the device when it is advertising. Radio operation is power intense and the advertising interval set to 100ms in beacon example (NON_CONNECTABLE_ADV_INTERVAL) gives the average power around 750-850uA average. If you change the NON_CONNECTABLE_ADV_INTERVAL from 100ms to 500ms, you can see that the average power drops from 750uA to around 500uA.

You can still change the program for beacon to go to deep sleep after the advertising timeout and call sd_power_system_off after configuring a wakeup source. You will then notice much less power consumption after advertisement timeout happened.

RE: power management

harrys — Wed, 30 Jun 2021 04:34:34 GMT

1. in ble_uart_example system goes to "system off sleep" ,mode after the completion of advertising duration.but what i did. i just commented "sd_power_system_off(deep sleep)" in sleep_mode_enter() declaration. now system working on "system on sleep" mode. rtc is working in sleep mode. and current is in uA.

2. in beacon example . beacon advertisement is continues(never timerout). i have changed duration to 500 to set 5 sec advertisement timer

m_adv_params.properties.type = BLE_GAP_ADV_TYPE_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED;
m_adv_params.p_peer_addr = NULL; // Undirected advertisement.
m_adv_params.filter_policy = BLE_GAP_ADV_FP_ANY;
m_adv_params.interval = NON_CONNECTABLE_ADV_INTERVAL;
m_adv_params.duration = 500;// 0; // Never time out.

as i see idle_state_handle() is called in for(;;). so it should go to system on sleep mode after advertisement duration. is there any wrong step i did. current is approx 1mA

RE: power management

Susheel Nuguru — Tue, 29 Jun 2021 16:30:07 GMT

You mentioned in your main description that the system is going to sleep in ble_app_uart and not in your beacon example? what do you mean by that? Did you measure power consumption on both and see that your beacon is taking much more power than you think it should?

Is the beacon advertising while you are measuring power?

Please read this thread understand the different sleep modes you can have on nRF52 devices

RE: power management

harrys — Tue, 29 Jun 2021 11:20:20 GMT

i don't want system in deep sleep mode. i want to run it in SYSTEM ON SLEEP mode. i want to know when i call _WFE system goes in "system on sleep" or not. if not can you tell me how i can do it.

RE: power management

Susheel Nuguru — Tue, 29 Jun 2021 11:15:46 GMT

sd_power_system_off(Deep sleep) is not the same as __WFE (Idle sleep).

Please use the same kind of sleeps to compare the results on both sides.