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Can't get BLE device to sleep

I have a custom PCBA with which has the flow of:

- Boot

- Advertise some temperature data read from TWI with a 5 second timeout using `ble_adv_fast_timeout`.

- I then set a timer to wake the `app_timer_start(m_awake_timer_id, APP_TIMER_TICKS(SLEEP_IN_MS), NULL);`

And I expect the device to go into sleep whilst its BLE is not advertising. Here's my main.c file:

#include "app_timer.h"
#include "nrf_pwr_mgmt.h"
#include "nrf_crypto_init.h"
#include "nrfx_clock.h"

#include "SEGGER_RTT.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#include "nrf_delay.h"

#include "customble.h"
#include "peripheral.h"
#include "encryption.h"

void timers_init(void)
{
  ret_code_t err_code = app_timer_init();
  APP_ERROR_CHECK(err_code);
}

static void idle_state_handle(void)
{
  if (NRF_LOG_PROCESS() == false)
  {
    nrf_pwr_mgmt_run();
  }
}

/**@brief Function for initializing power management.
 */
void power_management_init(void)
{
  ret_code_t err_code;
  err_code = nrf_pwr_mgmt_init();
  APP_ERROR_CHECK(err_code);
}

int main(void)
{
  NRF_LOG_INIT(NULL);
  NRF_LOG_DEFAULT_BACKENDS_INIT();

  ret_code_t reta = nrf_crypto_init();
  APP_ERROR_CHECK(reta);

  timers_init();
  ble_timers_init();
  ble_stack_init();

  power_management_init();

  gap_params_init();
  advertising_init();

  advertising_start();

  for (;;)
  {
    idle_state_handle();
  }
}

and here's the relevant sections of the customble.c code

void awake_timer_handler()
{
  NRF_LOG_INFO("Awake and start advertising");

  update_advertising_data_while_advertising();
  advertising_start();
}

void sleep_timer_handler()
{
  NRF_LOG_INFO("asleep");

  sd_ble_gap_adv_stop(m_advertising.adv_handle); // i've tried with and without this

  // Proceed with setting the device to low power mode
  app_timer_start(m_awake_timer_id, APP_TIMER_TICKS(SLEEP_IN_MS), NULL); // 60 seconds
}

void on_adv_evt(ble_adv_evt_t ble_adv_evt)
{
  NRF_LOG_INFO("BLE EVENT");
  switch (ble_adv_evt)
  {
  case BLE_ADV_EVT_IDLE:
    NRF_LOG_INFO("Advertising event: Idle");
    sleep_timer_handler();
    break;
  }
}

I have measured the amps on the device and during advertising it jumps to about 3mA and when it's not advertising (when I thought it would sleep) it's using ~1.48mA. What exactly am I doing wrong here?

I have commented lots of things out, and it's not the TWI causing the issue, it's definitely the BLE. When I comment out starting BLE, I get ~400uA constant.

  • Is this how you connected your custom HW?
    https://infocenter.nordicsemi.com/topic/ug_ppk/UG/ppk/PPK_user_guide_PPK_on_customHW_with_nRF5xDK.html?cp=11_10_5_4

    If so, which one of the figures did you follow? And did you make sure that all the switches are set in the position that are noted in the figures?

    I agree, your numbers seems a bit too high. 

    BR,

    Edvin

  • Yep, this is exactly how i've got it setup, I re-ran the test again today and got the same results.

    i'm going to start removing stuff from the program and see if i can identify what's causing this "active"state to be 80mA.

    The good news is:

    After going back to the hardware it seemed like the original problem was around the antenna. It seems like the incorrect antenna setup was causing the device to need more power (i'm guessing) for me to be able to receive a signal (perhaps why SYNTH worked fine best?).

    I have had a new set of prototype devices manufactured and I have set the device up as recommended 

    #define CLOCK_CONFIG_LF_SRC 0
    #define NRF_SDH_CLOCK_LF_SRC 0
    #define NRF_SDH_CLOCK_LF_RC_CTIV 16
    #define NRF_SDH_CLOCK_LF_RC_TEMP_CTIV 2
    #define NRF_SDH_CLOCK_LF_ACCURACY 1

    and the device now is advertising perfectly clearly:

    and now with the correct/recommended LF clock settings, we can see the sleep cycle is an actual sleep cycle:

    so I guess the only remaining thing is to work out the high power consumption when in bluetooth advertisement 

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