| 摘要 |
PROBLEM TO BE SOLVED: To provide an auxiliary package for wiring in which the waveform of the input pin of an IC (BGA etc.) having a bottom-face electrode can be observed in the vicinity of the input pin and, when the output pin of an unused output port etc., is disposed in the IC having the bottom-face electrode, a usable test pad can be laid out and a waveform shaping dumping pad can be disposed in the vicinity of the output pin and, when it is required to observe the many pins of the IC having the bottom-face electrode for verification, in addition, this package shortens the length of wiring and minimizes the number of used connectors. SOLUTION: In a printed board 13 which is sandwiched between the IC (BGA etc.) 12 having the bottom-face electrode and this auxiliary package 14 for wiring when the board 13 is mounted, pins to be observed in the IC (BGA etc.) 12 are connected to the auxiliary package 14 for wiring disposed immediately below the IC (BGA etc.) 12 through via holes and test pads 16 for waveform observation are disposed on the component mounting surface side of the package 14. Similarly, damping resistances and connectors are disposed on the component mounting surface side of the package 14. COPYRIGHT: (C)2004,JPO&NCIPI
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