| 摘要 |
<p>PURPOSE:To lower the ratio of a signal terminal of an I/O terminal in a multilayer interconnection substrate to a power-supply terminal by mounting a DC-DC converter on the multilayer interconnection substrate of an LSI package. CONSTITUTION:In power-supply systems of LSI packages 5, 15 where LSIs 41-44, 141-144 driven by three power supplies are mounted, a DC-DC converter 1 is mounted on a substrate of the LSI package 5; a single power supply supplied from its power-supply terminal 2 is converted info three power supplies required for the LSIS 41-44; electric power is supplied to the LSIs 41 44 via a power-supply wiring part 3. A power-supply bus 7 supplies power supplies to the LSI packages 5, 15; a signal bus 8 connects mutual signal systems via signal terminals 6, 16 of the LSI packages 5, 15.</p> |
