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:
Sep. 27, 2011
Filed:
Jun. 19, 2009
Ashish R. Jain, Santa Clara, CA (US);
Priya Ananthanarayanan, Cupertino, CA (US);
Greg M. Hess, Mountain View, CA (US);
Edgardo F. Klass, Palo Alto, CA (US);
Ashish R. Jain, Santa Clara, CA (US);
Priya Ananthanarayanan, Cupertino, CA (US);
Greg M. Hess, Mountain View, CA (US);
Edgardo F. Klass, Palo Alto, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A mechanism for measuring the variability of the read current of SRAM cells on an integrated circuit includes the integrated circuit having an SRAM array including a plurality of SRAM cells. The integrated circuit may also include a selection circuit configured to select a particular SRAM cell in response to a selection input. An oscillator circuit such as a ring oscillator, for example, on the integrated circuit may be configured to oscillate at a frequency that is dependent upon a read current of a selected SRAM cell during operation in a first mode. A frequency determining circuit that is coupled to the oscillator circuit may be configured to output a value corresponding to the frequency of oscillation of the oscillator circuit.