When the PC is placed in the ACPI S3 sleep state, the outputs are switched to the 5 V standby supply available in ATX style power supplies. In this state, the continuous output current is reduced to 100 mA, or to a user-adjustable value. This reduction protects the smaller current capacity of the standby supply in case of short-circuit faults. When the PC is returned to the active S0 state, the outputs are switched to the 5 V main supply. Make-before-break switching action guarantees glitch-free outputs during transitions between main and standby states.
The four devices introduced include the MIC2010, MIC2012, MIC2070 and MIC2072. The MIC2010 offers adjustable auxiliary current-limiting for more precise control, while the MIC2012 has pre-set current-limits for the auxiliary mode. The MIC2070 and MIC2072 provide a circuit breaker function that latches the output(s) off when an overcurrent condition is detected, reducing power consumption during a fault.