NRF52832 power leakage

[qyhok]

We use NRF52832   in the remote control of the car。We measured the average current of power consumption at about 1uA.Every 300ms, the current curve bounces to the transient current of 100uA, which we suspect is caused by charging and discharging of the DEC4 decoupling capacitor.We used the power supply of CR2032 to make 2000 samples. 10% of the samples ran out of battery power one month after they appeared. Theoretically, the battery could survive two years without changing.We did not initialize the idle pins, including NFC pin.I don't know what caused our power consumption. The real-time current of the sample retest was normal 1UA.We used SPIS, if configured "nrf_spis_pins_set(NRF_SPIS1,SPI_CLK_PIN,SPI_MOSI_PIN,NULL,SPI_CS_PIN)" This is going to affect the control of idle IO and I don't know what's wrong with the configuration。We also used PPI, mapped timer interrupt events, and GPIO rolloff。"nrf_power_system_off "The PPI needs to be turned off before the function, otherwise the power cannot be reduced.

• “nrf_gpio_cfg(LED_RED,    NRF_GPIO_PIN_DIR_INPUT,NRF_GPIO_PIN_INPUT_DISCONNECT,NRF_GPIO_PIN_PULLUP,NRF_GPIO_PIN_S0S1,NRF_GPIO_PIN_NOSENSE);”I don't really understand what NRF_GPIO_PIN_INPUT_DISCONNECT means,When I set pullup and disconnect ,the LED is off. set pulldown and disconnect the light is on .
• According to the block diagram, shouldn't the light be off as long as I set it off, no matter whether I pull it up or down?

[JONATHAN LL]

Hi,

We measured the average current of power consumption at about 1uA

10% of the samples ran out of battery power one month after they appeared

The real-time current of the sample retest was normal 1UA

 
So the 10% that "fail" was re-tested and you measured 1uA witch is what it should be ?


What is the size of your DEC4 capacitor?


When SPIS is active it is waiting for a interrupt on the CS pin, when this is happening it is expected that the current draw is 10-20uA


When you are measuring the average current how long is the period and does it include the 300ms jump? Are you able to measure a average current that would result in 1 moth life time for the battery?


Regards,
Jonathan

[qyhok]

JONATHAN LL said:

What is the size of your DEC4 capacitor?

1uF

• The average power consumption was very low, at 1.79 mWH after 100 minutes of measurement.

• When using button battery to independently power 52832, it was found that when charging DEC4 capacitor was needed, the peak current would make the battery voltage shake by 30~ 50mV. This process was seen to last for 30US by oscilloscope. I am not sure whether this process would lead to unstable operation or IO level failure.But when I switch to LDO-3V3 with a lithium battery, I do the same thing, but with a little wobble, 20mv.