Can't get BLE device to sleep

Question

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.

prsboy · Accepted Answer

Simonr Edvin 
 It's taken a long time, but I finally got myself hold of a PPK2 and the measurements are looking much more reasonable: 
 
 I think I can finally mark this as solved. I think to sum up the problems faced: 
 1. My setting of SYNTH for the clock LFCLK. This caused the device never to sleep. 
 2. The reason I needed SYNTH was that there was a hardware issue within the PCB design effecting the antenna which caused BLE not to be detectable using anything other than a configuration that caused the device to not be able to sleep (or otherwise be undetectable). 
 3. Once 2. was resolved, I could set LFCLK to RC Oscillator and use the recommended settings for the LFCLK 
 #define CLOCK_CONFIG_LF_SRC 0
#define NRFX_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 
 4. The PPK1 was giving unreliable readings for power measurement meaning that the readings were showing some clearly erroneous results. Purchasing a PPK2 to test helped show the correct power reading, which averages: 
 ~4.55uA 
 Thank you for your patience with this - it's been quite an puzzle on my side. Thanks for baring with me during it, I really appreciate the support, it's been top quality.

Can't get BLE device to sleep

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