[4] BUCK, SYSREG: Inserting USB causes VSYS voltage to undershoot

This anomaly applies to Revision 2, build codes CAAA-E00, CAAA-F00, CAAB-F00, QDAA-F00, QDAB-F00.

It was inherited from the previous IC revision Revision 1.

Symptoms

Inserting USB causes VSYS voltage to undershoot and BUCK converter to reset.

Conditions

USB power source has slow VBUS rise time in the range of 1 V/ms, battery voltage is below 3.1 V, and system load is higher than 370 mA.

Consequences

BUCK converter resets.

Workaround

If the system cannot tolerate a reset, avoid operating under the described conditions.

Parent topic: New and inherited anomalies