| 摘要 |
PURPOSE:To obtain a voltage limiter circuit which can be set on an integrated circuit together with the controllable limit voltage, the reduced variance of production and the excellent temperature characteristics, by connecting at least a constant voltage diode, an insulated gate type field effect transistor and a constant current circuit successively between an output terminal and an earth terminal. CONSTITUTION:The limit voltage is decided by a circuit where a constant voltage diode 3 and limit voltage controlling insulated gate field effect transistors IGFETs 4 and 5 are connected in series. The diode 3 uses the breakdown voltage adverse to a P-N-junction diode. It is possible to reduce the variance of the breakdown voltage down to several percents or less by putting the N and P type impurity diffusion areas close to each other on a mask centering on a line. While the limit voltage is controlled by the number of IGFETs 4 and 5 which are connected in series. |
