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:
Oct. 26, 1999
Filed:
Dec. 26, 1996
Chung K Chang, Sunnyvale, CA (US);
Johnny C Chen, Cupertino, CA (US);
Lee E Cleveland, Santa Clara, CA (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A low supply voltage negative charge pump for generating a relatively high negative voltage to control gates of selected memory cells via wordlines in an array of flash EEPROM memory cells during flash erasure includes charge pump means (210) formed of a plurality of charge pump stages (201-206) and coupling capacitor means (C201-C212) for delivering clock signals to the plurality of charge pump stages. Each of the plurality of charge pump stages is formed of an N-channel intrinsic pass transistor (N1-N6), an N-channel intrinsic initialization transistor (MD1-MD6), and an N-channel intrinsic precharge transistor (MX3-MX7, MX1) which are disposed in separate p-wells so as to reduce body effect. As a result, the negative charge pump is operable using a supply voltage of +3 volts or lower.