SG6520 is designed to provide the voltage, and current supervisor function, remote on/off (PSON) function, power good (PGO) indicator function, and fault protection (FPO) function for switching power systems.

For supervisor function, it provides the over voltage protection (OVP) for 3.3V, 5V and two 12V; over current protection (OCP) for 3.3V, 5V and two 12V; under voltage protection (UVP) for 3.3V, 5V and two 12V When 3.3V, 5V or 12V voltage is decreasing to 2.3V, 3.5V and 9V respectively, the under voltage protection (UVP) function will be enabled. FPO will be set to high to turn off the PWM controller IC. The voltage difference across external current shunt is used for OCP functions.

An external resistor can be used to adjust protection threshold. The power supply is turned on after 48mS delay time when PSON signal is set from high to low. To turn off power supply, PSON signal is set from low to high with the delay time 48mS. The PGI circuitry provides a power-down warning signal for PGO. When PGI input is lower than the internal 1.25V reference voltage, PGO signal is pulled low.