Additional current consumption on NRF52 DK board

[nimaaghli]

Hello,

I have NRF5230 DK board and I have powered the board with external battery. Solder bridge SB12 is shorted and I have cut the jumper SB29 and disabled power for Interface MCU.

I am measuring the current on on P22(P21 is shorted) with current meter device. I put the NRF chip in power off mode and and I have 1mA current consumption.while it should be micro amps!

Is there anything I have to disable to make correct current measurements?

[bjorn-spockeli]

Hi Nimaaghli, 

Where are you connecting the external battery if you have shorted P21? Also could you state what kind of current meter device you're using? It needs to have a dynamic range from nA to tens of mA in order to accurately calculate the average current consumption. 

It would also help if you attached the source code and the hex file so that I can perform measurements here.

Best regards

Bjørn 

[nimaaghli]

Thanks for the reply,

Sorry, I have stated it wrong, P21 is where my battery is connected and P22 is in default config(shorted) and I am using µCurrent GOLD to measure the current(My 3v battery`s + line goes to current meter then connects to + pin of the P21) which I believe is pretty accurate current meter. I am using BLE_Proximity without any changes. This example goes to sleep after some time when it is not connected to pair.  I expect to see very low current consumption at that point but it is still over 1mA.

I erase the chip and  the board is still consuming more than 1mA!

[nimaaghli]

Just ran this code and still 1.6mA

int main(void)
{
    err_code = sd_power_system_off();
    APP_ERROR_CHECK(err_code);
    while (true)
    {
    }
}

[nimaaghli]

Just shorted SB28(reset the Interface MCU) and current dropped to 400uA In sd_power_system_off(); Still lot of current to draw in power off mode!

[bjorn-spockeli]

Could you try running this code instead

/**@brief Function for application main entry.
 */
int main(void)
{
    NRF_POWER->SYSTEMOFF = 1;
    //Should never be reached
    while (true)
    {
    }
}

I did a measurement with the Nordic PPK and got the following result