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. 18, 2020
Filed:
May. 31, 2019
Apple Inc., Cupertino, CA (US);
Erhan Ozalevli, Santa Clara, CA (US);
Evaldo M. Miranda, Jr., Saratoga, CA (US);
Mohammad J. Navabi-Shirazi, San Jose, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
LED backlight circuits for a display and methods for operating the circuits are disclosed. The LED backlight circuit includes a set of drivers and a set of LED strings. A driver can control a light output level of the LED strings. The LED strings can be controlled by a mixed-mode LED driver that utilizes a PWM control signal over a first range of light output levels and an analog control signal over a second range of light output levels. Clock signals used for PWM control and for frequency-to-current or frequency-to-voltage conversion for analog control can both be generated from a phase locked loop (PLL).