| 摘要 |
<p>PURPOSE:To reduce the size and to enable free mounting/dismounting of a microcomputor by providing a first wiring board mounting only the microcomputor and a second wiring board mounting a plurality of associated circuit elements, accommodating the wiring boards in a hole made in one substrate, and mounting such circuit elements as producing heat mainly on the other substrate. CONSTITUTION:Power circuit elements producing heat are mainly mounted on the other substrate 2B superposed by a wiring board 8, a plurality of circuit elements 4 such as chip capacitors are mounted substantially on the entire area of the substrates 2A, 2B, and a microcomputor 7 and associated circuit elements 4 are mounted on a second wiring board 80. A hole 5 is made at a desired position of the substrate 2A, and the first wiring board 8 mounting the microcomputor 7 and the second wiring board 80 mounting the plurality of directly associated circuit elements 4 are disposed and accommodated in a space defined by the hole 5 and connected with conducting paths 3 formed on the other substrate 2B. By such arrangement, size can be reduced and the microcomputor 7 can be mounted/dismounted freely.</p> |
