low current value in sleep_mode_enter ()

RE: low current value in sleep_mode_enter ()

alex kim — Thu, 20 Feb 2020 00:58:39 GMT

Hi,

The cause of the reset is due to missing timers_init ().

Added timers_init (), so conn_params_init () run successfully.

The way to wakeup from systemoff is " devzone.nordicsemi.com/.../173257 " referenced.

Current consumption ranges from 0.1uA to 0.2uA in SystemOff mode.

Thank you for your kind reply.

Best regards,

Alex

RE: low current value in sleep_mode_enter ()

Stian Røed Hafskjold — Tue, 18 Feb 2020 16:06:53 GMT

Hello, you need to debug the application. Start the debugger and check the return values for all functions. Set breakpoints in main to see how far it goes before it resets.

RE: low current value in sleep_mode_enter ()

alex kim — Tue, 18 Feb 2020 01:49:53 GMT

Hi Stian,

Thank you for your quick and friendly reply.

I agree with you too.

But looking at the source code I can't figure out where this happens.

I zip the program and attach it.

I think it has entered SystemOff mode as the current draw drops to 0.6 ~ 0.7uA.

Alex

devzone.nordicsemi.com/.../sokey-_2D00_-52810.zip

RE: low current value in sleep_mode_enter ()

Stian Røed Hafskjold — Mon, 17 Feb 2020 10:34:46 GMT

Hi, the code is resetting. It starts the LFXO which takes 250ms, and during this time it's in idle mode consuming about 2uA. Then something happens and it resets. It never reaches the SYSTEMOFF line. So the current bursts you are seeing is the chip resetting.

RE: low current value in sleep_mode_enter ()

alex kim — Mon, 17 Feb 2020 01:09:53 GMT

HI,

I am using s112 for 52810.

I attached a hexa file.

I always appreciate your kind response.

Alex

devzone.nordicsemi.com/.../nrf52810_5F00_xxaa.hex

RE: low current value in sleep_mode_enter ()

Stian Røed Hafskjold — Fri, 14 Feb 2020 13:12:58 GMT

Are you sure that the code actually goes all the way to NRF_POWER->SYSTEMOFF = 1 line? I'm thinking that it hard faults and resets before it gets to that line, and that the current jumps you are seeing on the multimeter is actually the device restarting, over and over again.

Can you post the hex-file here, then I can try to run it and see what happens. If you can make sure that it is possible to run on a DK, not just your custom hardware, that would be great.

RE: low current value in sleep_mode_enter ()

alex kim — Fri, 14 Feb 2020 02:05:46 GMT

Hi,

I ran the code you recommended.

I also ran the existing code.

I've attached a video clip of the execution of the two kinds of code.

I attached sdk_config.h together.

Thank you

devzone.nordicsemi.com/.../20200214_5F00_104113.mp4

devzone.nordicsemi.com/.../20200214_5F00_104227.mp4

devzone.nordicsemi.com/.../8206.sdk_5F00_config.h

RE: low current value in sleep_mode_enter ()

Stian Røed Hafskjold — Thu, 13 Feb 2020 16:17:39 GMT

Hi, can you try to run just this code:

int main(void){
    NRF_POWER->SYSTEMOFF = 1;
    for(;;){}
}

What is the current consumption running the above code?

Can you describe your measurement setup? Thanks

RE: low current value in sleep_mode_enter ()

alex kim — Thu, 13 Feb 2020 11:40:58 GMT

Hi Kenneth,

We changed from 52840 to 52810.

Other conditions are the same.

I commented out init () according to your advice.

The measurement results of the current consumption varied between 0.6uA and 15.8uA.

I do not think this is the normal case.

I do not know why the current consumption changes in system off mode.

I ask for your advice.

Best regards,

Alex

devzone.nordicsemi.com/.../main_2D00_qna2.txt

RE: low current value in sleep_mode_enter ()

Kenneth — Tue, 11 Feb 2020 08:12:55 GMT

1. Yes.

2. You can always use external clock yes, check out NRF_SDH_CLOCK_LF_SRC and NRF_SDH_CLOCK_LF_ACCURACY in sdk_config.h

3. My next suggestion is to try to comment out init() code until you can identify the source of the current. What is the chip markings on the nRF52840 you are using?

Best regards,
Kenneth

RE: low current value in sleep_mode_enter ()

alex kim — Tue, 11 Feb 2020 02:02:19 GMT

Hi Kenneth,

Thank you for your kind reply.

1. By enabling and populating the DC/DC converter

#define POWER_ENABLED 1
#define POWER_CONFIG_DEFAULT_DCDCEN 1

err_code = sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);

Is it correct ?

2. by enabling/populating the 32kHz LFCLK crystal

I use BLE and the Advertising Interval is 1 second.

Can I use the 32KHz LFCLK Crystal even in this case?

How can I set if it is available?

3. I suspect floating input pin

I attach a function that initializes gpio and led.

Each input pin has a hardware pull-up

Best regards,

Alex

devzone.nordicsemi.com/.../gpio.c

RE: low current value in sleep_mode_enter ()

Kenneth — Mon, 10 Feb 2020 09:44:51 GMT

You may check out:
https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/optimizing-power-on-nrf52-designs

I suspect floating input pin; for instance you have configured a pin as input, however the pin is not connected to a defined level (e.g. low or high).