| 摘要 |
PURPOSE:To detect products to be rejected accurately at a high speed by measuring the reverse withstand voltage waveform and the forward voltage drop waveform of a semiconductor twice each to discriminate the characteristic thereof by comparing the waveforms separately. CONSTITUTION:When the first measurement of the reverse withstand voltage (PRV) waveform is performed with a measuring device 3, the action of a CPU30 is transmitted to a D/A converter 32 from an interface 31 according to a program and a reverse constant current amplifier 33 applied a reverse voltage (VR) to a diode 4 to be measured until the reverse current value is reached. When the first forward voltage drop (FDV) waveform measurement is performed, likewise, the output of the forward constant current amplifier 34 is flowed to the diode 4 being measured with the operation of the converter 32. Then, the output is fed back to the amplifiers 33 and 34 separately thereby enabling a control with the CPU30.
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