Radiation structure for heating element

摘要

A heating element (IC, transistor or the like) is placed on a printed circuit board and silicon grease is coated on the surface of the printed circuit board side of the heating element. The projection portion of a radiator with a step portion is inserted into the through hole of the printed circuit board and closely contacted with the lower portion of the heating element through the silicon grease. As a result, heat generated from the heating element is transferred to the projection portion of the radiator through the silicon grease and then transferred to the entirety of the radiator. Excessive silicon grease is collected in a step portion provided at the base of the projection portion of the radiator and prevented from leaking to other portion such as a portion on the board.