Hello,
I am working on a wearable device and need the lowest power consumption possible. The project configuration is:
The board is powered with a bench power supply which displayed current to mA resolution. I am not seeing any difference in power consumption when the DC/DC regulator is enabled. In previous projects there was a significant difference when this feature was enabled. It does not matter if it is before or after enabling the soft device/BLE.
As one final test I compiled the ble_app_template project in examples. This is the power consumption.
int main(void)
{
bool erase_bonds;
// Initialize.
log_init();
timers_init();
buttons_leds_init(&erase_bonds);
power_management_init();
ble_stack_init();
gap_params_init();
gatt_init();
advertising_init();
services_init();
conn_params_init();
peer_manager_init();
// Start execution.
NRF_LOG_INFO("Template example started.");
application_timers_start();
advertising_start(erase_bonds);
sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
// Enter main loop.
for (;;)
{
idle_state_handle();
}
}
Added a line to enable the DCDC converter.
The only other change was the sdk_config/sdh_lf_clock configuration to match our hardware.
There definitely seems to be something wrong with latest SDK and soft device.
Allen
As one final test I compiled the ble_app_template project in examples. This is the power consumption.
int main(void)
{
bool erase_bonds;
// Initialize.
log_init();
timers_init();
buttons_leds_init(&erase_bonds);
power_management_init();
ble_stack_init();
gap_params_init();
gatt_init();
advertising_init();
services_init();
conn_params_init();
peer_manager_init();
// Start execution.
NRF_LOG_INFO("Template example started.");
application_timers_start();
advertising_start(erase_bonds);
sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
// Enter main loop.
for (;;)
{
idle_state_handle();
}
}
Added a line to enable the DCDC converter.
The only other change was the sdk_config/sdh_lf_clock configuration to match our hardware.
There definitely seems to be something wrong with latest SDK and soft device.
Allen
Hi,
Allen said:Either I don't have the PPK setup properly or there may be a hardware issue? Below is a screen capture at startup. It appears that the baseline power consumption is [email protected] with only the BLE initialized. When the DCDC regulator is enabled the consumption actually went up! The capture you provided suggests that the baseline power should be around 5mA and with DCDC enabled it goes lower. I captured this several times to make sure my eyes were not deceiving me.
I'm not sure how you have connected your board to the PPK, but I do not think that 14 mA is caused by the nRF52832 chip alone, that would then have to be with the radio enabled in TX mode with highest output power, or radio and CPU running at the same time. "Baseline current" in my test is the CPU run current.
Allen said:First I need to verify that you used SDK 17.0.2 and S132 7.2.0 for your tests below? That code snippet could not be your main.c, is it?
The test I did was with nRF5 SDK v17.0.2, but without softdevice. The point was not to duplicate your setup but to show the timing of the DCDC enabling command. Apart from some header-include lines, that was the whole main.c file. I also wanted you to test this approach, to remove any softedevice issues from the case. By writing directly to the DCDCEN register, you could verify if the DCDC regulator works as expected on your board.
Allen said:Note: I discovered that the nRF52832 consumes 3.25mA *more* when running in debug mode. The following graphs are under debug control so we can see each step in the process.
In debug mode, the CPU and all clock sources are kept running, to handle the debug features. Higher current consumption is expected.
Allen said:I want back to the original code base which was SDK 15.2 and S132 6.0. This operation is very different.
Not sure what happens in this screenshot, but I think there is no way that the DCDC regulator can reduce the current from ~14 to under 4 uA.
Allen said:About 26 seconds after power on the consumption drops to 1.3mA and stays at that level.
This sounds like the CPU/chip went into sleep mode (System ON) with some peripheral requiring EasyDMA (UARTE/SAADC/etc) running.
Allen said:As one final test I compiled the ble_app_template project in examples. This is the power consumption.
I tested this on the nRF52 DK as well, with nRF5 SDK v17.0.2 and s132 v7.2.0:
No modifications:
Added sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE) at same line as you showed above:
This looks just as expected to me, so I do not think there is anything wrong with the softdevice or SDK.
Did you try to enable DCDC mode as the first thing in main(), by writing the register directly?
void main()
{
NRF_POWER->DCDCEN = 1;
//Your code after here
}