This anomaly applies to Revision 2, build code CAAA-Bxx.
It was inherited from the previous SoC revision Revision 1.
Symptoms
Using the mode where watchdog is paused in CPU Idle, the current consumption jumps from 3 µA to 400 µA.
Conditions
When we enable WDT with the CONFIG option to pause when CPU sleeps:
NRF_WDT->CONFIG = (WDT_CONFIG_SLEEP_Pause<<WDT_CONFIG_SLEEP_Pos);
Consequences
Reduced battery life.
Workaround
Do not enter System ON IDLE within 125 µs after reloading the watchdog.