Abstract: An IC tester includes a detection circuit for detecting a voltage level on a portion of a transmission line on a side thereof, which receives the output signal from an electronic device under test through the transmission line. A predetermined current is pulled in from the transmission line when the voltage level detected by the detection circuit is at a low level and a predetermined current equal to or different from the predetermined current to be pulled in is supplied to the transmission line when the detected voltage level detected by the detection circuit is at a high level.

Abstract: A diode element circuit uses a junction between the base and collector of a vertical type PNP transistor as a diode, and is further designed that a reverse bias voltage is applied between base and emitter of a parasitic PNP transistor in the vertical type PNP transistor, thereby, a diode having a small leakage current and a high break down voltage is realized without necessitating an additional manufacturing process.

Abstract: A diode element circuit uses a junction between the base and collector of a vertical type PNP transistor as a diode, and is further designed that a reverse bias voltage is applied between base and emitter of a parasitic PNP transistor in the vertical type PNP transistor, thereby, a diode having a small leakage current and a high break down voltage is realized without necessitating an additional manufacturing process.

Abstract: A semiconductor device according to the present invention comprises a first switch circuit connected between a transmission line and an input terminal of a comparator and adapted to be turned ON according to a change of a response waveform from High level to Low level to connect an impedance substantially equal to a characteristic impedance of the transmission line to the transmission line, a second switch circuit connected between the transmission line and the input terminal of the comparator and adapted to be turned ON according to a change of the response waveform from Low level to High level to connect an impedance substantially equal to the characteristic impedance of the transmission line to the transmission line, a first voltage generator circuit connected to the first switch circuit for generating a voltage for clamping the level of the response waveform at a certain Low level and a second voltage generator circuit connected to the second switch circuit for generating a voltage for clamping the level