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:
Apr. 24, 2001
Filed:
Jul. 17, 2000
Donald S. Gerber, Gilbert, AZ (US);
Kent Hewitt, Chandler, AZ (US);
Jeffrey A. Shields, Chandler, AZ (US);
Microchip Technology Incorporated, Chandler, AZ (US);
Abstract
A method of applying voltages to a memory cell, such as a P-channel EEPROM cell, and in particular to applying voltages to the cell during an erase operation of the cell is described. The method recognizes that during an erase, memory cells sharing deselected word lines are susceptible to a type of program disturb which is subtle and gradually causes corruption and loss of data over many programming cycles. The method of the present invention applies a voltage to deselected word lines, which is lower in magnitude than a programming voltage. This reduces the rate at which program disturb occurs, markedly increasing the number of programming cycles to which the deselected cells may be subjected before becoming susceptible to loss of data. The endurance of the memory array is thus significantly extended.