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:
Aug. 05, 2014
Filed:
Sep. 28, 2012
Apple Inc., Cupertino, CA (US);
Ravi K. Ramaswami, Cupertino, CA (US);
Geertjan Joordens, Sunnyvale, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A system and method for efficiently performing timing characterization of high-speed clocks signals with low-speed input/output pins. An integrated circuit includes a clock generator that generates a high-speed clock signal. A clock characterizer circuit receives the high-speed clock signal. The clock characterizer generates a corresponding low-speed clock signal. The generated low-speed clock signal is output through a low-speed general-purpose input/output (GPIO) pin for measurement. The generated low-speed clock signal is sent to a sequential element for staging. The staging of the generated low-speed clock signal is done with sequential elements that use a reverse polarity of a clock signal than the polarity used by a previous stage. The high-speed clock signal is used for the staging. The output of each stage is sent to a low-speed GPIO pin for measurement.