This anomaly applies to IC Rev. Revision 2, build codes SICA-B1A, SIBA-B1A, SIAA-B1A.
It was inherited from the previous IC revision
Revision 1.
Symptoms
Regulators staying in LDO mode causes higher current consumption.
Conditions
Startup from reset.
Consequences
- The device current consumption will be higher. Exactly how much higher depends on the difference in efficiency in DC/DC and LDO regulators at a given supply level and the current draw of the device.
- The device is qualified using DC/DC converters. Qualifications and certificates created without DC/DC converters will hence be void.
Workaround
Application software needs to set the regulators into DC/DC mode before starting up the modem. Set register at startup as described below. For secure mode:
NRF_REGULATORS_S->DCDCEN = REGULATORS_DCDCEN_DCDCEN_Enabled << REGULATORS_DCDCEN_DCDCEN_Pos;
For non-secure mode:
NRF_REGULATORS_NS->DCDCEN = REGULATORS_DCDCEN_DCDCEN_Enabled << REGULATORS_DCDCEN_DCDCEN_Pos;
Note: Workaround included as of MDK 8.21.1 and later releases.