| 摘要 |
<p>PURPOSE:To improve the solderability of outer leads on a surface mounting in an electronic device having a surface mounting type package by reducing the area of the contacting surface of the outer leads with a land pad smaller than that of the lateral section of the leads. CONSTITUTION:An IC1 is so disposed on a circuit substrate 21 as to align outer leads 5 to land pads 22 wired and formed on the substrate 21 to be placed, and soldered between the pads 22 and the leads 5. The cutouts 11 cut at both sides of the leads 5 are so opened as to oppose to the upper surface of the pads 22, which is covered with a solder plating film 15. Accordingly, the solder materials at both sides of the contacting surface 10 of the pads 22 are effectively sucked to the surface of the cutouts 11 to be increased by means of its surface tension, thereby forming a solder part 23 of extremely thick layer. Thus, the reliability or external performance of the connection after surface mounting can be enhanced.</p> |
