| 摘要 |
<p>PURPOSE:To protect the semiconductor element mounted on a printed circuit board from electrostatic breakdown by electrically connecting the earth pattern of the printed circuit board and a protective cover by the conductive member having elasticity held between the earth pattern and the protective cover. CONSTITUTION:A conductive member having elasticity, for example, a small conductive rubber plate 15 to which conductivity is provided by the dispersion of a fine carbon powder is held between the earth pattern 11a of a printed circuit board 11 and a frame 12 in a compressed state. Therefore, a protective cover 13 and the earth pattern 11a of the printed circuit board 11 are always electrically connected by the conductive rubber plate 15. Even when an operator is accidently charged with static electricity when he holds an IC card by his hand to mount the same on electronic machinery, static electricity successively flows through the protective cover 13, the conductive rubber plate 15, the earth pattern 11a of the printed circuit board 11, a connector 14 and the electronic machinery to be discharged and does not flow through the semiconductor element 16 mounted on the printed circuit board 11.</p> |
