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:
Jun. 07, 2011
Filed:
Jul. 08, 2005
Chih-heng Chu, Tainan County, TW;
Ming-cheng Chiu, Tainan County, TW;
Chih-Heng Chu, Tainan County, TW;
Ming-Cheng Chiu, Tainan County, TW;
Himax Technologies Limited, , TW;
Abstract
A current driving apparatus and method using a pulse width modulation (PWM) technique to display a desired gray level for passive matrix organic light emitting diode (PMOLED) display applications is disclosed. The current driving circuit includes a memory, a logic and a segment driver. The memory stores a desired gray level, the logic comprises a counter and provides a predetermined bias time, and the segment driver provides a constant current to the PMOLED display based on the desired gray level and the predetermined bias time. The segment driver provides a constant current to the PMOLED display until the counter value reaches the desired gray level, and the counter is first counted zero for the predetermined bias time and then increments by one for every other cycle.