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:
Oct. 31, 2000
Filed:
May. 08, 1997
Mehrdad Nayebi, Palo Alto, CA (US);
Duc Ngo, San Jose, CA (US);
Sony Corporation, Tokyo, JP;
Sony Electronics, Inc., Park Ridge, NJ (US);
Abstract
A luminance signal generation circuit with single clamp generates a separate luminance signal Y by combining RGB input signals in a weighted manner within a Y-Matrix circuit. During a burst period the single clamping circuit is enabled. When enabled, the single clamping circuit compares the separate luminance signal Y to a constant reference voltage signal. A difference signal, representing the difference between the separate luminance signal Y and the constant reference voltage signal, is used to adjust a blanking level of the RGB input signals until the blanking level of the separate luminance signal Y is equal to the constant reference voltage signal. During the non-burst periods the single clamping circuit is disabled and the Y-Matrix circuit combines the RGB input signals into the separate luminance signal Y. Preferably, the single clamping circuit sets the blank level of the separate luminance signal Y to a level equal to two volts. NPN transistor follower circuits are utilized within the clamping circuit and with input receiving circuits to provide the RGB input signals to the Y-Matrix circuit.