SEMICONDUCTOR VOLTAGE CONTROLLER FOR VARIABLE SPEED MOTOR-DRIVEN TOOL

摘要

PURPOSE:To obtain a voltage controller having good heat sink with small outer profile size by containing a hybrid integrated circuit device mounted on the surface of a ceramic circuit substrate with a power control element chip and a chip-shaped circuit constituent of a control circuit in a sheathed metallic case. CONSTITUTION:A power control element chip 21 coated and dried with protecting resin 21b through a copper plate 21a is mounted on the surface of a ceramic circuit substrate 20 formed with a thick film wire conductor, and a control circuit 22 which is composed of a switching element chip or diode element chip 22a coated and dried with protecting resin 22a1 and a laminated chip condenser 22b for controlling the operation of the power chip 21 is mounted on the surface of a substrate 20 surrounded as designated by one-dotted chain line. Further, an external lead wire 23 is formed at the edge of the side of the chip 21. In this manner, a voltage controller which has small outer profile size and good heat sink can be inexpensively obtained.