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:
Mar. 14, 2000
Filed:
Mar. 18, 1999
Seiki Ogura, Wappingers Falls, NY (US);
Tomoko Ogura, Wappingers Falls, NY (US);
Halo LSI Design & Device Technology, Inc., Wappingers Falls, NY (US);
Abstract
In this invention a reference circuit is disclosed that produces a reference current to be used in determining the value of data in a flash memory cell. The memory cell current is compared to the reference current in a sense amplifier. A reference circuit that generates the reference current is connect to each bit line of the flash memory and uses bit lines that are not activated when a particular cell is being read to connect the reference current to the sense amplifiers. The use of a reference current allows multi-bit cells to be read by using a variation on the reference circuit that has a plurality of reference transistors creating a plurality of reference currents.. Verification of the programmed and erase states of a flash memory cell can be determined using different values of the reference current that are easily set in the reference circuit by changing a reference voltage.