| 摘要 |
PURPOSE:To obtain a monitor circuit with which threshold voltages of field- effect transistors MOS-FET by a method wherein predetermined currents are applied to the respective MOS-FET's through first and second pads and the potentials of the respective pads are measured. CONSTITUTION:In a monitor circuit for an N-type channel MOS-FET, the drain and gate of an N-type channel transistor Tn are short-circulated with each other and connected to a pad P1 and the source and back-gate of the transistor Tn are connected to the lowest potential (each potential) part Sub in a substrate. At the time of testing, a tester TE having a constant current source 1 is connected between the pad P1 and the lowest potential part Sub and a predetermined current is applied to the transistor Tn to facilitate the test of the threshold voltage of the MOS-FET. Further, the drain and gate of a p-type channel transistor Tp are short-circuited with each other and connected to a pad P2 and the highest potential VDD in the substrate is applied to the source and back-gate of the transistor Tp. At the time of testing, the tester TE having the constant current source 1 is connected between the pad P2 and the highest potential VDD to facilitate the test of the threshold voltage. |
