Renesas Technology Corp.

Hitachi Maxell, Limited

Hitachi Microcomputer System, Ltd.

Takehisa Yokohama

Fujio Ito

Takafumi Kikuchi

Takeshi Yamaguchi

Noriaki Sakamoto

Shinji Tanaka

Tomoru Sato

Eiji Matsumasa

Kouichi Horisaki

Yosifumi Sakaguchi

To provide a test technology capable of reducing a package size by reducing a number of terminals (pins) in a semiconductor integrated circuit of SIP or the like constituted by mounting a plurality of semiconductor chips to a single package, in SIPconstituted by mounting a plurality of semiconductor chips to a signal package of ASICSDRAMand the like, a circuit of testing SDRAM(SDRAMBIST) is provided at inside of ASICand SDRAMis tested from outside of SDRAMthat is, from ASICBy providing the test circuit of SDRAMat inside of ASICit is not necessary to extrude a terminal for testing SDRAMto outside of SIP

Semiconductor integrated circuit

A protection circuit device for protecting a secondary battery from an overcharge and/or an overdischarge has first and second terminals, across which a charger and a load are alternatively connectable. A first switch and/or a second switch may be provided in series with the secondary battery between the first and second terminals. In a charging operation mode, the second switch is kept conductive. A charging operation is performed with the first switch made conductive. When the battery is overcharged for some reasons, the first switch is turned off. Upon connection of a load across the first and second terminals, the first switch is restored to a conductive state for a discharging operation which releases the battery from an overdischarge state. In a discharging operation mode, the first switch is kept conductive. A discharge operation is performed with the second switch made conductive. When the battery is overdischarged, the second switch is caused to remain conductive even after commencement of the overdischarge, so that the battery can continue the discharge operation if the temporary overdischarge does not last longer than the predetermined period of time.

Secondary battery protection device from overcharge/overdischarge

Growing community of inventors

Higashiyamato, Japan

Takehisa Yokohama