-
公开(公告)号:US20200090599A1
公开(公告)日:2020-03-19
申请号:US16510635
申请日:2019-07-12
Applicant: Apple Inc.
Inventor: Vehbi Calayir , James E. Brown
Abstract: Aspects of the subject technology relate to control circuitry for light-emitting diodes. The control circuitry may include feedforward control and a feedback control for a power supply for the light-emitting diodes. The feedforward control may include host circuitry for the device that determines a maximum zone current, a maximum row current, and the maximum row-to-row current step for an upcoming backlight frame while a current backlight frame is being executed. A headroom voltage for the upcoming backlight frame is determined based on the maximum zone current, the maximum row current, and/or the maximum row-to-row current step and provided to the power supply so that the power supply can settle at a corresponding supply voltage before the upcoming backlight frame is executed. The feedback control utilizes dynamic thresholds determined for each backlight frame to fine tune the feedforward-determined headroom voltage.