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:
Nov. 17, 2009
Filed:
May. 28, 2008
Gary D. Carpenter, Austin, TX (US);
Jente B Kuang, Austin, TX (US);
Kevin J. Nowka, Georgetown, TX (US);
Liang-teck Pang, Albany, CA (US);
Gary D. Carpenter, Austin, TX (US);
Jente B Kuang, Austin, TX (US);
Kevin J. Nowka, Georgetown, TX (US);
Liang-Teck Pang, Albany, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A pulsed ring oscillator circuit for storage cell read timing evaluation provides read strength information. A pulse generator is coupled to a bitline to which the storage cell to be measured is connected. The storage cell thereby forms part of the ring oscillator and the read strength of the storage cell is reflected in the frequency of oscillation. A pulse regeneration circuit is included in the ring so that the storage cell read loading does not cause the oscillation to decay. Alternatively, a counter may be used to count the number of oscillations until the oscillations decay, which also yields a measure of the read strength of the storage cell. The pulse generator may have variable output current, and the current varied to determine a change in current with the storage cell enabled and disabled that produces the same oscillation frequency. The read current is the difference between currents.