The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 17, 2007
Filed:
Jun. 30, 2005
Ryo Mori, Higashiyamato, JP;
Toshio Yamada, Kokubunji, JP;
Tetsuya Muraya, Hamura, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
The present invention provides a semiconductor integrated circuit device having an SRAM in which leak current is reduced. In an SRAM comprising a plurality of memory cells each constructed by a storage in which input and output terminals of two inverter circuits are cross-connected and a selection MOSFET provided between the storage and complementary bit lines and whose gate is connected to a word line, a substrate bias switching circuit is provided. In normal operation, the substrate bias switching circuit supplies a power source voltage to an N-type well in which a P-channel MOSFET of a memory cell is formed and supplies a ground potential of the circuit to a P-type well in which an N-channel MOSFET is formed. In the standby state, the substrate bias switching circuit supplies a predetermined voltage which is lower than the power source voltage and by which a PN junction between the N-type well and the source of the P-channel MOSFET is not forward biased to the N-type well, and supplies a predetermined voltage which is higher than the ground potential and by which a PN junction between the P-type well and the source of the N-channel MOSFET is not forward biased to the P-type well.