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. 24, 2007
Filed:
Jan. 21, 2004
Applicants:
Ming-chu King, Taichung, TW;
Chia-wen Shiue, Toucheng Township, Yilan County, TW;
Inventors:
Ming-Chu King, Taichung, TW;
Chia-Wen Shiue, Toucheng Township, Yilan County, TW;
Assignee:
Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu, TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R 23/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A test circuit for identification of locations with low speed performance. A grid of ring oscillator units and switches connect or disconnect the ring oscillator units to or from each other, such that the locations with low speed performance are identified according to frequencies of oscillation signals generated by rows and columns of ring oscillators respectively formed by operating the test circuit in two different modes.