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:
Dec. 29, 2020
Filed:
May. 21, 2019
Apple Inc., Cupertino, CA (US);
Jingdong Chen, San Jose, CA (US);
Asif Hussain, San Jose, CA (US);
Mohammad J. Navabi-Shirazi, San Jose, CA (US);
Behzad Mohtashemi, Los Gatos, CA (US);
Yanhui Xie, Santa Clara, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
A display may have display layers that form an array of pixels. The array of pixels may be illuminated using a backlight unit. The backlight unit may include multiple strings of light-emitting diodes (LEDs). The multiple LED strings may be controlled by one or more backlight driver integrated circuits (ICs). In a multi-driver IC architecture, an enable signal may be used to set a desired phase delay between the multiple ICs. One or more of the LED strings may exhibit a short fault. Depending on the number of faulty LED strings, the backlight unit can selectively throttle the maximum brightness of the display. The LED strings may receive an output voltage from a DC/DC converter and may be driven using a current driver. The DC/DC converter may be controlled by a headroom feedforward control circuit to ensure sufficient headroom for the current driver while suppressing acoustic noise.