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. 27, 1999
Filed:
May. 21, 1997
Thomas P Bushey, Phoenix, AZ (US);
James S Caravella, Chandler, AZ (US);
David F Mietus, Phoenix, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A circuit (28) and method of sensing data stored in a memory circuit provide a reference current (I.sub.REF) that tracks memory cell current (I.sub.BIT) over a range of temperatures and power supply voltages. A comparator circuit (66) senses the memory cell current with respect to the reference current to produce the stored data (V.sub.DATA) By sensing current rather than voltage, the voltage swing on a high capacitance bitline (39) can be reduced to improve speed. The reference current is set during testing of the circuit by applying programming voltages (V.sub.WELL, V.sub.CG, V.sub.BL) to a reference device (52) that matches a storage device (36) in the memory cell (30).