1. Technical Field
The present invention relates to a test apparatus, a performance board, and a calibration board.
2. Related Art
A semiconductor test apparatus measures several types of characteristics of a semiconductor device under test (DUT). For example, a semiconductor test apparatus may input to a semiconductor device a test signal generated by an arbitrary waveform generator (AWG). In this case, the measurement is performed after a waveform digitizer performs a high-speed and highly accurate digital conversion on the signal output from the semiconductor device. In this way, the semiconductor test apparatus can test whether the semiconductor device is operating properly.
Japanese Patent Application Publication No. 7-209354 and Japanese Patent Application Publication No. 3-296308 are related prior art documents.
The arbitrary waveform generator and the waveform digitizer include analog circuits that transmit analog signals. An ideal analog circuit outputs an analog signal having a prescribed frequency corresponding to the input signal. In practical application, however, the analog circuit outputs an analog signal that includes harmonic wave components caused by the non-linear characteristics of the elements in the analog circuit. As a result, waveform distortion occurs in the output signal.
By inputting a signal having a single frequency and no distortion into the analog circuit and calculating the difference between the input signal and the signal output by the analog circuit to identify the distortion, a distortion signal can be acquired that indicates the distortion caused by the analog signal. In other words, the non-linear distortion caused by the analog circuit can be compensated for if the acquired distortion signal is subtracted from the signal output by the analog circuit. However, different identification techniques are used for the arbitrary waveform generator and the waveform digitizer. Therefore, it is necessary to provide an apparatus that performs the identification for the arbitrary waveform generator and an apparatus that performs the identification for the waveform digitizer, which increases the size and the cost of the semiconductor test apparatus.