Patent ID: 8803501

Claim:
A power supply apparatus for a test apparatus, configured to supply a power supply voltage to a device under test, the power supply apparatus comprising: a voltage source configured to generate the power supply voltage stabilized such that its voltage level matches a voltage level that corresponds to a reference voltage, and to supply the power supply voltage thus generated to the device under test; a current detection circuit configured to generate a detection voltage that corresponds to an output current that flows through the device under test; and a reference voltage generating circuit configured to generate the reference voltage according to an input voltage and the detection voltage, wherein the voltage source comprises: an operational amplifier configured to receive a feedback voltage corresponding to the power supply voltage and the reference voltage; and a buffer configured to receive an output voltage of the operational amplifier and to output the power supply voltage, wherein the reference voltage generating circuit is configured to generate the reference voltage such that, in an initial state, the reference voltage is set to an initial voltage level that corresponds to the input voltage, and such that, after the output current flows, the reference voltage transits to a first voltage level obtained by shifting the initial voltage level by a first voltage step that corresponds to the detection voltage, following which the reference voltage transits to a second voltage level obtained by shifting the initial voltage level by a second voltage step that corresponds to the detection voltage.