Patent ID: 7880470

Claim:
A test apparatus that tests a device under test, comprising: a signal output device that outputs an output signal according to a test signal to the device under test; and a detecting section that detects a signal output from the device under test in accordance with the output signal and outputs a detection result, the signal output device comprising: an output port that outputs the output signal; a high-voltage side switching circuit that opens or short-circuits between a first terminal connected to a high-voltage side reference voltage generating port for outputting a high-voltage side reference voltage and a second terminal connected to the output port in accordance with a first control signal; a low-voltage side switching circuit that opens or short-circuits between a first terminal connected to the output port and a second terminal connected to a low-voltage side reference voltage generating port for outputting a low-voltage side reference voltage lower than the high-voltage side reference voltage in accordance with a second control signal; and a control section that outputs the first control signal and the second control signal according to a logical value shown by the input signal causing the high-voltage side switching circuit to be opened when the low-voltage side switching circuit is being short-circuited and causing the low-voltage side switching circuit to be opened when the high-voltage side switching circuit is being short-circuited, and each of the high-voltage side switching circuit and the low-voltage side switching circuit comprising: a plurality of switching devices that is serially connected between the first terminal and the second terminal and each of which is opened or short-circuited in accordance with a provided control voltage; and control circuits that is provided corresponding to the plurality of switching devices, which provides a control voltage according to the control signal to the corresponding switching device, and that opens and short-circuits the plurality of switching devices substantially in synchronization with each other, wherein a voltage inputted to the first terminal is outputted from the second terminal by short-circuiting between the first terminal and the second terminal.