xdot intermittent excess power draw during sleep

[Chad Goyette]

I am currently doing a power study on an in house developed solution that uses the xDot module. we have been noticing excessive power consumption during the sleep cycle that intermittently happens. our typical power draw in the sleep cycle (2 min cycle) is approximately 10uA. we have been noticing that after the device goes to sleep approximately 4.6 seconds into the cycle the current jumps to 17.5mA. This current jump does not happen on every sleep cycle but there does not seem to be a pattern on when it happens. We are versy sure that nothing else is running on the board and it must be the xDot drawing the power. I am running libxdot-mbed5 version 3.1.0 with mbed-os version 5.7.7.
our custom application is very simple in its normal running state. it polls 4 sensors every 2 min and transmits data if the values change from the previous send. in between polls the device sleeps. we use the following code to put the xDot to sleep: the functions within are from a copy of the dot_util library within the dot-examples application.
void xdotSleep(int sTime)
{
sleep_save_io();
sleep_configure_io();
dot->sleep(sTime, mDot::RTC_ALARM, false);
sleep_restore_io();
}

Any help on this is appreciated.
Thanks

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