| 摘要 |
<p>PURPOSE:To reduce the size of an entire semiconductor device by integrally projecting a plurality of mounting plates at an interval on a cover and cooling fin to be mounted in a containing box, and mounting a printed board which places electronic parts including a semiconductor element, thereby reducing a thermal resistance. CONSTITUTION:A cover and cooling fin 8 is mounted on a bottom of a containing box 5, and a plurality of mounting plates 8a are projected at a predetermined interval from the fin 8 toward the hole end of the box 5. Then, printed boards 1 each of which places electronic parts such as a triac element 3, a photocoupler 3, etc. are secured to one side surfaces of the plates 3a, and external circuit connecting terminals 4 are led therefrom toward the hole end. Thereafter, a filler 7 having large thermal conductivity is loaded in an air gap formed between the plates 8a. Thus, a heat sink action is improved to increase the number of boards 1 to be contained in the box 5 of small size.</p> |
