Patent ID: 8089258

Claim:
A power supply apparatus, comprising: a first power supplier, configured for receiving a direct current (DC) input voltage and generating a DC output voltage accordingly, the first power supplier comprising: a main power generating unit, configured for receiving and converting the DC input voltage so as to generate a main power accordingly; a first resistor having a first terminal coupled to the main power generating unit and receiving the main power; an isolation diode having an anode coupled to a second terminal of the first resistor and a cathode outputting the DC output voltage; a second resistor having a first terminal coupled to the anode of the isolation diode; a voltage feedback controller, coupled to a second terminal of the second resistor and the main power generating unit, configured for providing a control signal to control the main power generating unit according to a voltage of the second terminal of the second resistor, so as to regulate the main power; and a current detecting unit, coupled to the first terminal and the second terminal of the first resistor, configured for detecting a current flowing through the first resistor, so as to output an adjustment signal for controlling a voltage of the second terminal of the second resistor substantially equal to a voltage of the cathode of the isolation diode, and thus making the first power supplier stably output the DC output voltage.