公开(公告)号：US10237936B2

公开(公告)日：2019-03-19

申请号：US15784943

申请日：2017-10-16

Applicant: Apple Inc.

Inventor： Mohammad J. Navabi-Shirazi ,  Alejandro Lara Ascorra ,  Asif Hussain ,  Ji Yeoul Ryoo ,  Jingdong Chen ,  Jun Qi ,  Manisha P. Pandya ,  Yanhui Xie

IPC: H05B37/02 ,  H05B33/08 ,  G02F1/1335 ,  G02F1/13357 ,  G02F1/1343

Abstract: Aspects of the subject technology relate to control circuitry for light-emitting diodes. The control circuitry may operate a light-emitting diode using a multi-peak pulse-width-modulation signal. The control circuitry may include a multi-stage driver having a relatively larger driver stage for providing a direct current through a light-emitting diode and a relatively smaller driver stage configured to cooperate with a pulse-width-modulation controller to pulse-width-modulate a current through the light-emitting diode.

公开(公告)号：US20180019081A1

公开(公告)日：2018-01-18

申请号：US15211818

申请日：2016-07-15

Applicant: Apple Inc.

Inventor： Alejandro Lara Ascorra ,  Qian Zhang ,  Thai Q. La

IPC: H01H13/83 ,  G06F3/02

CPC classification number: H01H13/83 ,  G06F1/1616 ,  G06F1/1662 ,  G06F3/0202 ,  H01H2219/039

Abstract: Systems and methods for selective keyboard backlighting with reduced driver circuitry are provided. In one example embodiment, a method includes, inter alia, simultaneously controlling, with a control signal, an output of a first light emitting element that illuminates only one key of a plurality of keys of a keyboard and an output of a second light emitting element that illuminates only one key of the plurality of keys, and maintaining, with a current mirror circuit, uniformity between the output of the first light emitting element and the output of the second light emitting element.

公开(公告)号：US20130278175A1

公开(公告)日：2013-10-24

申请号：US13659890

申请日：2012-10-24

Applicant: APPLE INC.

Inventor： Alejandro Lara Ascorra ,  Eric G. Smith ,  Steven J. Sfarzo

IPC: H05B37/02

CPC classification number: H05B33/0842

Abstract: One embodiment of a display backlight driver integrated circuit can be configured for operation in at least two different ways. A first method transfers data from an EEPROM to hardware registers prior to regular operation. A second method also transfers data from an EEPROM to registers. However, hardware registers can be overwritten with data accepted from a control bus, prior to regular operation. A keyboard driver IC can detect the presence or absence of a cable to an LED. If the cable is absent, the driver IC will not supply power for the LED. One embodiment of a keyboard and display backlight control system can be configured to allow substantially independent operation.

Abstract translation: 显示器背光驱动器集成电路的一个实施例可被配置为以至少两种不同的方式进行操作。 第一种方法是在正常操作之前将数据从EEPROM传输到硬件寄存器。 第二种方法还将数据从EEPROM传输到寄存器。 但是，在正常操作之前，硬件寄存器可以被从控制总线接受的数据覆盖。 键盘驱动器IC可以检测到LED的电缆的存在或不存在。 如果电缆不存在，驱动器IC将不会为LED供电。 键盘和显示器背光控制系统的一个实施例可以被配置为允许基本独立的操作。