| 摘要 |
PURPOSE:To make it possible to analyze the defective operation of a semiconductor element, which is operated at a low voltage, without destruction, by forming the input signal and the power source terminal voltage of the semiconductor element as the synthesized voltage, which is obtained by superimposing a high frequency pulse voltage on a DC or a low frequency AC voltage. CONSTITUTION:The input signal or power source terminal voltage of a semiconductor element, in which the effect of the electric field of a nematic liquid crystal 4 is applied, is made to the synthesized voltage, which is obtained by superimposing a high frequency pulse voltage on a DC or a low frequency AC voltage. For example, a low frequency AC voltage (or DC voltage) 12, which has the speed that can be visually recognized, and a high frequency voltage 13, which causes double refractions in incident light all the time, are prepared. When the high frequency voltage 13 is superimposed on the low frequency AC voltage 12, the wave form of the synthesized voltage 14 is formed. A semiconductor element is operated so that the signal is applied on wirings 2a and 2b in the semiconductor elements. Then, the signal is turned ON and OFF at the low frequency. Therefore the movement can be recognized visually. Since the liquid crystal 4 is actually moved by the high frequency pulses, charge-up phenomenon does not occur and incident light undergoes double refractions. Thus the operating state of the semiconductor element can be visually recognized. |
