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. 09, 2004
Filed:
Mar. 17, 2003
Cheng-Lin Chung, Hsinchu, TW;
Nien-Chao Yang, Hsinchu, TW;
Macronix International Co., , TW;
Abstract
A sense amplifier inverts the output from the pass transistor to control a pre-charge transistor. The combination of the inverter and pre-charge transistor pre-charges the output to a level just below the flip level of the following data latch circuit. If the data cell read is a low threshold cell (conductive or “1”), the output level does not significantly change, and the data is rapidly latched and read. If the data cell is a high threshold cell (non-conductive or “0”), the pass transistor shuts off and the output is pulled up above the flip level of the data latch circuit through a pull-up path. The pre-charge level is near the flip level, so the output does not have to be pulled up very far, thus reading a “0” is also fast. In one embodiment, the pull-up transistor is a p-channel MOSFET with the gate grounded, thus providing more constant current than a diode-connected configuration. In another embodiment, the pull-up transistor is operated as a current mirror using a cell in a mini array. The first inverter of the data latch circuit can be used in the feedback path to the precharge transistor, or a separate feedback inverter can be provided.