| 摘要 |
PURPOSE:To protect thermal runaway, by making a rim-continuous, metalized electrode with mid-part being separated, at both ends in the longitudinal direction of a good heat-conductive insulator, transmitting generated heat of transistors on the electrode to diodes on the electrode, and lowering base voltage. CONSTITUTION:Metalized electrodes 22, 23, which continuously cover the top, bottom, and both sides, are made with mid part being separated on both ends of a good heat-conductive plate 21 like beryllia ceramics. A transistor 8 and a diode 9 are soldered on the electrodes 22 and 23 respectively. The plate 21 is soldered on the top of an insulating substrate 19. The bottom of an electrode 10 is soldered on a collector electrode 10. The bottom of the electrode 23 is soldered on an emitter electrode 11, and the wiring is performed as necessary. This constitution makes heat generation of the transistor transmitted efficiently to the diode through the beryllia ceramic plate. The base voltage is lowered quickly, and the transistor is prevented from heat runaway, thereby obtaining the desired circuit increased in its reliability. |
