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:
Jan. 18, 2000
Filed:
Dec. 08, 1997
Kiyoshi Nishimura, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
An object of the present invention is to provide a semiconductor device having a ferroelectric capacitor wherein the ferroelectric capacitor is difficult to get bad electric property. In a capacitor unit CbU for load, a bridge circuit is made including a ferroelectric capacitor Cb for load, transistors Q1, Q2, Q3 and Q4. The both ends of the bridge circuit is connected with a bit line /BL1 and the ground G, respectively. A line SWS is connected with the gates of both transistors Q1 and Q3 and further is connected with the gate of both transistors Q2 and Q4 via an inverter 104. A switch-signal generating circuit 102 shifts the level of switch signal for the line SWS whenever the number of leading edges of the line GCP reaches a predetermined number. According the shifted switch signal, the direction of the capacitor Cb for load in its bridge circuit is changed. That can prevent the capacitor Cb for load from getting a bad electric property.