The RT9228 monitors all the output voltages. A Power-good signal is issued when the core voltage is within 10% of the DAC setting and the other levels are above their under-voltage levels. Additional buildin over-voltage protection for the core output uses the lower MOSFET to prevent output voltage above 115% of the DAC setting. The PWM over-current function monitors the output current using the voltage drop across the upper MOSFET's RDS(ON), which eliminates the need for a current sensing resistor.