POWER SUPPLY CIRCUIT WITH POWER SUPPLY RAILS INDEPENDENTLY MONITORED FOR LOAD ATTACKS

Certain aspects of the present disclosure provide techniques and apparatus for supplying power. One example power supply circuit generally includes a switching regulator including an output coupled to a first power supply rail for coupling to a first load and to a second power supply rail for coupling to a second load, a battery node for coupling to a battery, a switch coupled between the battery node and the second power supply rail, and a logic circuit including a first input coupled to the first power supply rail, a second input coupled to the second power supply rail, and an output coupled to a control input of the switch, the logic circuit being configured to control closing of the switch when a voltage of the first power supply rail falls below a first threshold voltage or a voltage of the second power supply rail falls below a second threshold voltage.