JP2865400B

PURPOSE:To make it possible to inhibit the routing-around of a conductive passage of a mother board and facilitate function tests and troubleshooting by fixing separatedly a sub-board to said mother board at a specified position and wire-bonding the mutual connection of said conductive passage. CONSTITUTION:A support section 34 of a sub-board 30 is fixedly soldered with a pad 20 formed on a mother board 10 where a pad 42 formed on the sub-board 30 is wire-bonded with a pad 28 formed on the mother board 10, thereby interconnecting an electronic circuit of the mother board 10 with an electronic circuit of the sub-board 30, which makes jumping connections for a conductive passage formed on the mother board 10. Since a chip device is used as an integrated circuit, a high degree of integration can be attained and moreover, the conductive passage of the mother board can be mutually connected with the conductive passage of the sub-board at any arbitrary position. This construction makes it possible to avoid a reduction in a package area due to the routing- around of the conductive passage, and facilitate functional tests after the interconnection of the conductive passage and troubleshooting as well.