Patent attributes
A characteristic test of a DUT having a low transmission line driving capability can be performed with a simple configuration and low cost. An impedance matching circuit is connected between a transmission line and a DUT in an input-output circuit of a semiconductor test apparatus. The impedance matching circuit includes: a resistance; an analog computing unit which multiplies a voltage from one end of the resistance by a predetermined number, subtracts a voltage from the other end of the resistance from the voltage multiplied by the predetermined number and outputs a resultant voltage; and a buffer which outputs a signal from the analog computing unit with low impedance. The impedance matching circuit produces an output signal from the DUT with low impedance, thereby sufficiently driving the transmission line.