Patent ID: 6479877
Filing Date: 2002-11-12
Classification: H01L

Abstract:
A semiconductor device comprising:a substrate; a main MOS transistor formed on the substrate for supplying a current to a load, the main MOS transistor being composed of a first lateral type MOS transistor and forming a current path in a direction parallel to a surface of the substrate; and a sense MOS transistor formed on the substrate and connected to the main MOS transistor in parallel to form a current mirror circuit with the main MOS transistor for controlling the current supplied to the load, the sense MOS transistor being composed of a second lateral type MOS transistor and forming a current path in a direction parallel to the surface of the substrate, wherein: the sense MOS transistor and the main MOS transistor share a same region of the substrate and the sense MOS transistor forms a polygonal shape on a surface of the substrate in cooperation with the main MOS transistor; the sense MOS transistor extends to pass through a corner and a center of the polygonal shape; and the main MOS transistor and the sense MOS transistor have a plurality of drain cells and a plurality of source cells that are arranged in a mesh shape, a contour of which forms the polygonal shape on the substrate; and the sense MOS transistor includes first and second drain cells that are respectively arranged on the corner and the center of the polygonal shape, the first and the second drain cells being electrically connected to each other.