SEMICONDUCTOR DEVICE & CIRCUIT SUITABLE FOR USE IN INTELLIGENT POWER SWITCH

摘要

A semiconductor device and a circuit suitable for use in an intelligent power switch are described. The semiconductor device provides an insulated gate field effect transistor (IGFET) (T2) and a power semiconductor switch (T1). The insulated gate field transistor IGFET (T2) is provided by a semiconductor body (6) which has a first region (7) of one conductivity type adjacent a given surface (6a) of the semiconductor body with the first region (7) forming at least part of a conductive path to a first main electrode of the power semiconductor switch. A second region (8) of the opposite conductivity type is provided within the first region adjacent the given surface (6a) and a third region (11) of the one conductivity type isprovided adjacent the given surface (6a) within the second region (8), an area of the second region (8) underlying an insulated gate (14) provided on the given surface (6a) for defining a conduction channel (15) providing a gateable connection between the third region (11) and a fourth region (12) of the one conductivity type. The third and fourth regions (11 and 12) forming the source and drain regions of the IGFET and the second and third regions (8 and 11) together provide a zener diode, a conductive path being provided to the second region remote from the area underlying the insulated gate for reverse-biassing the zener diode. The IGFET may comprise a synchronous rectifier of a charge pump for providing a gate voltage signal to the power semiconductor switch which may be a power MOSFET (T2).