公开(公告)号：US20230085621A1

公开(公告)日：2023-03-23

申请号：US17853247

申请日：2022-06-29

Applicant: Apple Inc.

Inventor： Behzad Mohtashemi ,  Asif Hussain ,  Feng Guo ,  Jingdong Chen ,  Ming Gu ,  Mohammad J. Navabi-Shirazi ,  Omar Alnaggar ,  Venkataraman V. Iyer ,  Yang Zhang

IPC: G09G3/20

Abstract: A display device include a first light emitting diode (LED), a second LED, and at least one processor of a driver. The processor drives the first LED and the second LED. The processor determines a first pulse width associated with the first LED and a second pulse width associated with the second LED based on a level of brightness to be emitted by the first LED and the second LED. The processor also receives a gap clock and determines a first pulse start time and a first pulse end time for the first LED based on the first pulse width. Moreover, the processor determines a second pulse start time and a second pulse end time for the second LED based on the first pulse end time, the second pulse width, and/or the gap clock, in which the first pulse end time and the second pulse end time are different.

公开(公告)号：US11442312B2

公开(公告)日：2022-09-13

申请号：US17203311

申请日：2021-03-16

Applicant: Apple Inc.

Inventor： David W. Lum ,  Jingdong Chen ,  Mingxia Gu ,  Jun Qi

IPC: G02F1/1335 ,  G02F1/13357 ,  H05B47/16 ,  H05B47/105 ,  H01L25/16 ,  G09G3/34

Abstract: A pixel array may be illuminated with backlight illumination from a backlight. The backlight may include a two-dimensional array of light-emitting diodes, with each light-emitting diode being placed in a respective cell. Different light-emitting diodes may have unique brightness magnitudes based on the content of the given display frame. Driver integrated circuits may control one or more associated light-emitting diodes to have a desired brightness level. The driver integrated circuits may be formed in an active area of the backlight. The driver integrated circuits may be arranged in groups that are daisy chained together. A digital signal (that includes information such as addressing information) may be propagated through the group of driver integrated circuits. To manage thermal performance of the backlight, the backlight may include a thermally conductive layer and/or a heat sink structure. To increase the efficiency of the backlight, the backlight may include one or more reflective layers.

公开(公告)号：US10678092B2

公开(公告)日：2020-06-09

申请号：US15711932

申请日：2017-09-21

Applicant: Apple Inc.

Inventor： Ji Yeoul Ryoo ,  Asif Hussain ,  Jingdong Chen ,  Mohammad J. Navabi-Shirazi ,  Yanhui Xie

IPC: G06F5/00 ,  G02F1/13357 ,  G09G3/34 ,  G09G3/36 ,  H05B45/00 ,  H05B45/37 ,  H05B45/46 ,  H05B47/10 ,  G02F1/1335 ,  G06F3/041

Abstract: Aspects of the subject technology relate to display circuitry such as backlight control circuitry for operating parallel strings of light-emitting diodes (LEDs). A voltage supply circuit of the backlight control circuitry provides a common supply voltage to the strings of LEDs. Headroom control circuitry samples a residual voltage at the end of each string, determines a minimum of the residual voltages, and provides feedback, based on the determined minimum voltage, to the voltage supply circuit. A headroom control feedback loop may be provided including sampling lines coupled to the second end of each string of LEDs for sampling a residual voltage of each string. Headroom control circuitry may modify the supply voltage based on the minimum residual voltage. Sample-and-hold circuitry may be provided that holds the sampled residual voltages until the voltage supply circuit is ready for an update.

公开(公告)号：US10555389B2

公开(公告)日：2020-02-04

申请号：US16232913

申请日：2018-12-26

Applicant: Apple Inc.

Inventor： Yanhui Xie ,  Asif Hussain ,  Jingdong Chen ,  Manisha P. Pandya

IPC: H05B37/00 ,  H05B33/08 ,  G02F1/1335

Abstract: Aspects of the subject technology relate to display of an electronic device. The display includes a backlight unit having a voltage source, a string of light-emitting diodes and a bypass switch for each light-emitting diode in the string. The string of light-emitting diodes can receive, at a first end, a supply voltage from the voltage source. The bypass switch for each light-emitting diode is controllable to pulse-width-modulate that light-emitting diode. The headroom voltage feedback circuit is coupled to a second end of the string.

公开(公告)号：US10009968B2

公开(公告)日：2018-06-26

申请号：US15069724

申请日：2016-03-14

Applicant: Apple Inc.

Inventor： Jingdong Chen ,  Asif Hussain ,  Behzad Mohtashemi ,  Manisha P. Pandya ,  Mohammad J. Navabi-Shirazi

IPC: H05B33/08 ,  G09G3/34

CPC classification number: H05B33/0815 ,  G09G3/3406 ,  G09G2330/06 ,  H05B33/086

Abstract: This application relates to systems, methods, and apparatus for controlling a switching frequency of a boost or flyback converter to be above an audible frequency range when operating the boost or flyback converter in a pulse frequency modulation (PFM) mode. The boost or flyback converter uses one or more switches for converting power for a display panel. In order to boost the switching frequency when operating in the PFM mode, the boost or flyback converter can selectively implement certain current and/or voltage limits for pulses that are generated as a result of the switching. The current and/or voltage limits can be set according to a load of the boost or flyback converter, and a correspondence between the current and/or voltage limits and the loads can be stored in a lookup table accessible to the boost or flyback converter.

公开(公告)号：US09380672B2

公开(公告)日：2016-06-28

申请号：US13754640

申请日：2013-01-30

Applicant: Apple Inc.

Inventor： Asif Hussain ,  Jingdong Chen ,  Mohammad Jafar Navabi-Shirazi ,  Manisha Pandya

IPC: H05B33/08 ,  G09G3/34

CPC classification number: H05B33/086 ,  G09G3/3406 ,  G09G2320/041 ,  G09G2320/062 ,  G09G2320/064 ,  H05B33/0863

Abstract: An electronic device may be provided with display circuitry that includes a display timing controller, a backlight driver, a light source, and other associated backlight structures. The backlight control circuitry may generate a control signal having an adjustable duty cycle to the backlight driver. The backlight driver may include a boost converter, a current driver, and backlight control circuitry. The current driver may only be activated when the control signal is high. The backlight control circuitry may output an enable signal to the boost converter. The backlight control circuitry may activate the boost converter a predetermined amount of time before each rising clock edge in the control signal by asserting the enable signal for a longer period of time than when the control signal is high. The control signal and the enable signal may be deasserted at around the same times.

Abstract translation: 电子设备可以设置有显示电路，显示电路包括显示定时控制器，背光驱动器，光源和其它相关联的背光结构。 背光控制电路可以产生对背光驱动器具有可调占空比的控制信号。 背光驱动器可以包括升压转换器，电流驱动器和背光控制电路。 当控制信号为高电平时，只能激活当前驱动器。 背光控制电路可以向升压转换器输出使能信号。 背光控制电路可以在控制信号中的每个上升时钟沿之前的预定时间量内激活升压转换器，该时间长于当控制信号为高时，将使能信号置为更长的时间段。 控制信号和使能信号可以在大约相同的时间被解除。

公开(公告)号：US20140176352A1

公开(公告)日：2014-06-26

申请号：US14029534

申请日：2013-09-17

Applicant: APPLE INC.

Inventor： Asif Hussain ,  Mohammad J. Navabi-Shirazi ,  Jingdong Chen ,  Manisha P. Pandya

IPC: H01H13/83

CPC classification number: H01H13/83 ,  G06F3/0202

Abstract: Systems, devices, and methods for a shared matrix of shared row pins and/or column pins between a first array of keys and a second array of lights of a keyboard. A keyboard controller addresses the first array of keys and the second array of lights during a scanning period using the shared row pins and/or column pins. Each key is backlit by one or more lights of the second array of lights that may be individually controlled. The keyboard controller may drive the desired lights of a respective row while detecting key presses of the same row during the row interval using the shared row pins and/or column pins. In some embodiments, the keyboard controller may drive the desired lights of a row during driving interval of the row interval, and scan the keys of the row separately during a sensing interval of the row interval.

Abstract translation: 用于共享行引脚和/或列引脚的共享矩阵在键的第一阵列与键盘的第二阵列之间的系统，设备和方法。 键盘控制器在扫描周期期间使用共享行引脚和/或列引脚来寻址第一阵列的键和第二阵列的光。 每个键都可以由可以单独控制的第二阵列灯的一个或多个灯背光。 键盘控制器可以在使用共享的行引脚和/或列引脚的行间隔期间检测同一行的按键时驱动相应行的期望的光。 在一些实施例中，键盘控制器可以在行间隔的驱动间隔期间驱动行的期望光，并且在行间隔的感测间隔期间单独扫描行的键。

公开(公告)号：US11876439B2

公开(公告)日：2024-01-16

申请号：US17450910

申请日：2021-10-14

Applicant: Apple Inc.

Inventor： Yanhui Xie ,  Asif Hussain ,  Jingdong Chen ,  Zhiyuan Hu

IPC: H02M1/14 ,  H02M1/00 ,  H02M3/04

CPC classification number: H02M1/14 ,  H02M1/0077 ,  H02M3/04

Abstract: A battery powered electronic device can include a battery to power one or more loads, a first DC-DC converter having an input coupled to the battery and an output, and a second DC-DC converter cascaded with the first DC-DC converter and coupled to a second load subject to pulsed operation. The first and second converters may be configured so as to isolate the one or more loads from transients associated with the pulsed operation of the second load. The second converter may have an input coupled to the output of the first converter and an output coupled to the second load. Alternatively, the second converter may be a bidirectional converter having first terminals coupled to the output of the first converter and second terminals coupled to an energy storage device.

公开(公告)号：US10269307B2

公开(公告)日：2019-04-23

申请号：US15683648

申请日：2017-08-22

Applicant: Apple Inc.

Inventor： Yanhui Xie ,  Asif Hussain ,  Jingdong Chen ,  Mohammad J. Navabi-Shirazi

IPC: G09G3/34 ,  H05B33/08

Abstract: Aspects of the subject technology relate to control circuitry for operating light-emitting diodes (LEDs). The control circuitry may include a pulse-width-modulation (PWM) driver for the LEDs and headroom voltage control circuitry. The PWM driver may adjust a rising edge or a trailing edge of the PWM cycles for various LEDs to ensure a headroom voltage detection window for the headroom voltage control circuitry to sample the headroom voltage of those LEDs without being affected by the rising edge of the PWM cycle for LED or the falling edge of the PWM cycle for another LED.

公开(公告)号：US11694641B2

公开(公告)日：2023-07-04

申请号：US17870576

申请日：2022-07-21

Applicant: Apple Inc.

Inventor： Behzad Mohtashemi ,  Mohammad J Navabi-Shirazi ,  Feng Guo ,  Omar Alnaggar ,  Venkataraman V Iyer ,  Jingdong Chen ,  Yang Zhang ,  Ming Gu ,  Asif Hussain

IPC: G09G3/34

CPC classification number: G09G3/3406 ,  G09G2310/08 ,  G09G2320/064

Abstract: Systems and methods for preserving a pulse width modulation (PWM) resolution while increasing the frequency of a pulse width modulation (PWM) clock are provided. An electronic display backlight system may include a backlight element and backlight dimming circuitry. The backlight element may be driven according to a pulse width modulation (PWM) signal over a PWM clock cycle equal to a multiple M of a baseline PWM clock frequency associated with a baseline PWM resolution. The backlight dimming circuitry may receive a brightness code of the baseline PWM resolution and generate the PWM signal at least in part by dividing the brightness code by M.