PURPOSE: To enable to mount or demount the IC/LSI to or from a printed substrate without stopping a function by incorporating a battery backup circuit into an insulator.

CONSTITUTION: Substrate fitting sections 11 and contacting sections 12 are constituted as integral metallic pins, and function as paths for input/output signals among ICs/LSIs inserted and printed substrate wirings. Semiconductor elements 14 and resistors 15 and the like are connected to batteries 13, and they are incorporated and fixed into the insulator 10 made of a resin, thus constituting the battery backup circuit for the ISs/LSIs. Accordingly, the ICs/LSIs can be replaced and carried under the state in which there is no possibility that memory contents, etc. written in the ICs/LSIs disappear in the socket in which the battery backup circuit and an auxiliary supply battery for a backup are incorporated.