Source code to achieve 1.5uA standby current

[Sridhar Jonnavittula]

Hi all,

I wanted to see this below screen shot current number on nRF52840 DK

For that I changed peripheral/blinky example main() like this but I am seeing 14uA.

/* Configure board. */
//bsp_board_init(BSP_INIT_LEDS);

NRF_POWER->RAM[0].POWERCLR = 0xFFFF;
NRF_POWER->RAM[1].POWERCLR = 0xFFFF;
NRF_POWER->RAM[2].POWERCLR = 0xFFFF;
NRF_POWER->RAM[3].POWERCLR = 0xFFFF;
NRF_POWER->RAM[4].POWERCLR = 0xFFFF;
NRF_POWER->RAM[5].POWERCLR = 0xFFFF;
NRF_POWER->RAM[6].POWERCLR = 0xFFFF;
NRF_POWER->RAM[7].POWERCLR = 0xFFFF;
NRF_POWER->RAM[8].POWERCLR = 0xFFFF;

/* Toggle LEDs. */
while (true)
{
__WFE();
#if 0
for (int i = 0; i < LEDS_NUMBER; i++)
{
bsp_board_led_invert(i);
nrf_delay_ms(500);
}
#endif
}

Can anyone please provide me the source code to achieve that 1.5uA number?

Thanks

Sridhar

[Simonr]

Hi

Susheel is out of office, so I have been assigned your case. In order to achieve this current consumption on the Development Kit (DK), you have to power the board through VDDH. There are a few ways to do this on the DK. Check out Section 8.3 (Power Supply) in the DK user guide. The recommended option is using the Lithium polymer battery connectors J6 or P27 (2.5V-5.0V).

Best regards,

Simon

[Sridhar Jonnavittula]

Ok. Please answer couple of questions:

1. I actually tried attaching 5V from external regulated power supply to VIN 3–5 pin on P20 (3.0–5.0 V)(This is the only source). In this condition when I read the MAINREGSTATUS register I see A=0 (Normal voltage VDD). Why is it so?

2. When I supply from Li-Po/ other than USB J2 port, I cant use Power profiler kit right? In this case do I need Oscilloscope?

Thanks