公开(公告)号：US20170208661A1

公开(公告)日：2017-07-20

申请号：US15478549

申请日：2017-04-04

Applicant: Apple Inc.

Inventor： Asif Hussain ,  Jingdong Chen ,  Manisha P. Pandya ,  Adrian E. Sun

IPC: H05B33/08

CPC classification number: H05B33/0851 ,  G09G3/3426 ,  H05B33/0818

Abstract: A backlight driver chip for an electronic device includes an input that receives data corresponding to a brightness of a backlight device. The backlight driver chip also includes correction circuitry that determines an amplitude correction factor based at least in part on the data and the brightness of the backlight device. The correction circuitry also determines a corrected brightness based at least in part on the amplitude correction factor. The backlight driver chip further includes an output that provides a current signal that drives the backlight device, wherein the current signal is based at least in part on the corrected brightness.

公开(公告)号：US20160329820A1

公开(公告)日：2016-11-10

申请号：US15148870

申请日：2016-05-06

Applicant: Apple Inc.

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

IPC: H02M3/335 ,  H02M1/08

CPC classification number: H02M3/33523 ,  H02M1/32 ,  H02M2001/0009

Abstract: Various systems and methods are disclosed herein, which provide isolated systems with an auxiliary, multi-signal digital feedback loop for reporting a plurality of different potential fault conditions in an output system (e.g., output short circuit, output over-voltage, output under-voltage, output over temperature, etc.) to a Primary Controller in an input system. The signals may be sent according to any desired standardized (or proprietary) data transmission protocols. Use of a digital feedback loop allows the signals to be passed to the Primary Controller more quickly than is allowed by traditional analog feedback paths—and while using only a single optocoupler device for the transmission of all fault conditions. The techniques disclosed herein are applicable to any number of isolated systems that supply power to electronic systems such as: digital cameras, mobile phones, watches, personal data assistants (PDAs), portable music players, monitors, as well as desktop, laptop, and tablet computers.

Abstract translation: 本文公开了各种系统和方法，其为隔离系统提供辅助的多信号数字反馈回路，用于在输出系统中报告多个不同的潜在故障状况（例如，输出短路，输出过压， 电压，输出温度等）输入到输入系统中的主控制器。 可以根据任何期望的标准化（或专有）数据传输协议发送信号。 数字反馈回路的使用允许信号比传统的模拟反馈路径更快地传递到主控制器，而在仅使用单个光耦合器件来传输所有故障条件时。 本文公开的技术适用于向电子系统供电的任何数量的隔离系统，例如：数码相机，移动电话，手表，个人数据助理（PDA），便携式音乐播放器，监视器以及桌面，膝上型计算机和 平板电脑

公开(公告)号：US20160276928A1

公开(公告)日：2016-09-22

申请号：US15050152

申请日：2016-02-22

Applicant: Apple Inc.

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

IPC: H02M3/156

CPC classification number: H02M3/156 ,  H02M2003/1566

Abstract: A power conversion circuit, such as a buck converter/regulator, includes a feedback loop operatively coupling the output voltage to the controller for the switching mechanism. The feedback loop includes an analog error amplifier that sources current to the controller when the output voltage falls below a predetermined reference voltage and sinks current from the controller when the output voltage rises above a predetermined reference voltage. The feedback loop further includes at least one of a sinking boost circuit that sinks additional current from the controller when the output voltage falls below a low voltage threshold or a sourcing boost circuit that sources additional current to the controller when the output voltage rises above a high voltage threshold. The boost circuits can include analog amplifiers, digital comparators, or a combination thereof.

Abstract translation: 诸如降压转换器/调节器的功率转换电路包括将输出电压可操作地耦合到用于开关机构的控制器的反馈回路。 反馈回路包括模拟误差放大器，当输出电压下降到低于预定参考电压时，向输入电压发送电流，并在输出电压升高到高于预定参考电压时从控制器吸收电流。 所述反馈回路还包括吸收升压电路中的至少一个，当所述输出电压下降到低电压阈值以下或者当所述输出电压升高到高于所述控制器的时候向所述控制器提供额外电流的源极升压电路，所述吸收升压电路吸收来自所述控制器的附加电流 电压阈值。 升压电路可以包括模拟放大器，数字比较器或其组合。

公开(公告)号：US09185768B2

公开(公告)日：2015-11-10

申请号：US13940181

申请日：2013-07-11

Applicant: Apple Inc.

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

IPC: G06F1/26 ,  H05B33/08 ,  H02M3/156 ,  H02M1/00

CPC classification number: H05B33/0887 ,  G06F1/26 ,  H02M3/156 ,  H02M2001/0025 ,  H05B33/0815 ,  H05B33/0884 ,  Y02B20/341

Abstract: A measured voltage drop across a power-line transistor is used as a sensing element to measure the current and detect an over-current condition for an LED backlight system. An over-current or short condition is detected when the measured voltage drop exceeds a threshold. Accurate detection of the over-current condition is achieved by calibrating the RDS-ON (i.e., internal resistance between drain and source, when transistor is on) of the power-line transistor. In one embodiment, the calibration of RDS-ON is performed by ramping down the threshold from an initial value and using the tripped threshold to determine the actual value for RDS-ON. In another embodiment, the calibration of RDS-ON is performed by using two thresholds, a first threshold to calibrate RDS-ON and a second threshold to detect the over-current condition.

Abstract translation: 电力线晶体管两端的测量电压降被用作传感元件，以测量电流并检测LED背光系统的过电流状态。 当测量的电压降超过阈值时，检测到过电流或短路状况。 通过校准电源线晶体管的RDS-ON（即，在晶体管导通时漏极和源极之间的内部电阻）来实现过电流状态的精确检测。 在一个实施例中，RDS-ON的校准是通过从初始值降低阈值并使用跳闸阈值来确定RDS-ON的实际值来执行的。 在另一个实施例中，通过使用两个阈值来执行RDS-ON的校准，第二阈值是用于校准RDS-ON的第一阈值和用于检测过电流状态的第二阈值。

公开(公告)号：US08970200B2

公开(公告)日：2015-03-03

申请号：US13673695

申请日：2012-11-09

Applicant: Apple Inc.

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

IPC: H02M3/158 ,  H02M3/04 ,  G09G5/10

CPC classification number: G09G5/10 ,  G09G3/3406 ,  G09G2300/0426 ,  G09G2320/0233

Abstract: Systems and methods for light-load efficiency in displays may include a backlight driver circuit that may adjust a gate drive voltage provided to a gate of a metal-oxide-semiconductor field-effect transistor (MOSFET) in the boost converter based on the load conditions of light-emitting diodes used to illuminate the display panel. The backlight driver circuit may also switch between two different voltage sources to further broaden a range of gate drive voltages available to drive the gate of the MOSFET in the boost converter. As a result, the backlight driver circuit may decrease gate drive losses associated with the MOSFET, thereby increasing the efficiency of the boost converter.

Abstract translation: 显示器中轻负载效率的系统和方法可以包括背光驱动器电路，其可以基于负载条件来调节提供给升压转换器中的金属氧化物半导体场效应晶体管（MOSFET）的栅极的栅极驱动电压 的用于照亮显示面板的发光二极管。 背光驱动器电路还可以在两个不同的电压源之间切换，以进一步扩大可用于驱动升压转换器中的MOSFET的栅极的栅极驱动电压的范围。 结果，背光驱动器电路可以减小与MOSFET相关联的栅极驱动损耗，从而提高升压转换器的效率。

公开(公告)号：US20140247295A1

公开(公告)日：2014-09-04

申请号：US14276132

申请日：2014-05-13

Applicant: APPLE INC.

Inventor： Asif Hussain ,  Manisha P. Pandya

IPC: G09G3/36 ,  H05B33/08

CPC classification number: G09G3/3611 ,  G09G3/3406 ,  G09G2300/0426 ,  G09G2330/028 ,  G09G2330/06 ,  G09G2330/08 ,  G09G2340/0457 ,  H05B33/0827 ,  H05B33/0893

Abstract: Disclosed embodiments relate to techniques for operating a backlight unit of a display device in a redundant mode and a non-redundant mode in the event of an open circuit condition or short string condition. For instance, in a redundant mode, multiple LED strings are driven to provide a first quantity of light, such that the combined output from all LED strings is capable of providing a total light output corresponding to a maximum brightness setting for the display device. In the case that one of the LED strings fails due to an open circuit condition or short string condition, the remaining LED strings may be driven to provide a second quantity of light that is greater than the first, such that the combined light output from the remaining LED strings provides the same total light output for achieving the maximum brightness setting. Further, if the LED strings are operated in a phase-shifted manner, the phase shift between the remaining LED strings may be dynamically adjusted to keep the phase shift substantially equal between the LED strings.

Abstract translation: 公开的实施例涉及在开路状况或短串条件的情况下以冗余模式和非冗余模式操作显示装置的背光单元的技术。 例如，在冗余模式中，多个LED串被驱动以提供第一数量的光，使得来自所有LED串的组合输出能够提供对应于显示装置的最大亮度设置的总光输出。 在LED串中的一个由于开路条件或短串条件而失效的情况下，可以驱动剩余的LED串以提供大于第一数量的第二量的光，使得从 剩余的LED串提供相同的总光输出以实现最大亮度设置。 此外，如果LED串以相移的方式操作，则可以动态地调整剩余LED串之间的相移，以保持LED串之间的相移基本相等。

公开(公告)号：US20140097765A1

公开(公告)日：2014-04-10

申请号：US13679781

申请日：2012-11-16

Applicant: APPLE INC.

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

IPC: H05B37/02

CPC classification number: H05B37/02 ,  G09G3/3426 ,  H05B33/0869

Abstract: Devices and methods for controlling brightness of a display backlight are provided. A display backlight controller may control the brightness of the display backlight by changing a duty cycle of a PWM signal that drives the LED current. However, because of LED efficacy and response time, the final output brightness (NITS) may not be linear between 0% to 100%. The disclosed methods may be used to correct the brightness using a predetermined correction factor. Further, the minimum and maximum duty cycle of the output dimming duty cycle may be limited or corrected. In one example, a backlight controller receives an input duty cycle and determines a product of the input duty cycle and a maximum duty cycle to produce a reduced duty cycle. Moreover, the backlight driver may determine a corrected duty cycle using the correction factor. The final output duty cycle and LED current may then be determined.

Abstract translation: 提供了用于控制显示器背光的亮度的装置和方法。 显示器背光控制器可以通过改变驱动LED电流的PWM信号的占空比来控制显示器背光的亮度。 然而，由于LED效能和响应时间，最终的输出亮度（NITS）可能在0％到100％之间不是线性的。 所公开的方法可以用于使用预定的校正因子校正亮度。 此外，可以限制或校正输出调光占空比的最小和最大占空比。 在一个示例中，背光控制器接收输入占空比并且确定输入占空比和最大占空比的乘积以产生减小的占空比。 此外，背光驱动器可以使用校正因子来确定校正的占空比。 然后可以确定最终的输出占空比和LED电流。

公开(公告)号：US11121573B1

公开(公告)日：2021-09-14

申请号：US15476652

申请日：2017-03-31

Applicant: Apple Inc.

Inventor： InHwan Oh ,  Zaki Moussaoui ,  Rohan Dayal ,  Bharat K. Patel ,  Manisha P. Pandya ,  Weihong Qiu ,  Malhar V. Bhatt

IPC: H02J7/02 ,  H02J50/12 ,  H02J50/90

Abstract: A power converter can be implemented as a series of power conversion stages, including a wireless power conversion stage. In typical embodiments, the power converter receives power directly from mains voltage and outputs power to a battery within an electronic device. A transmitter side of the power converter converts alternating current received from a power source (e.g., mains voltage) to an alternating current suitable for applying to a primary coil of the wireless power conversion stage of the power converter.

公开(公告)号：US10601250B1

公开(公告)日：2020-03-24

申请号：US15476472

申请日：2017-03-31

Applicant: Apple Inc.

Inventor： InHwan Oh ,  Shimon Elkayam ,  Manisha P. Pandya

IPC: H02J50/00 ,  H02J50/05 ,  H02J50/12 ,  H02J7/02 ,  H02J50/40 ,  H02J50/80

Abstract: A half bridge power converter can be coupled to, or included in, a wireless transmitter device. The half bridge power converter includes an upper switching element connected between a direct current supply voltage and a lower switching element. A duty controller is coupled to the upper and the lower switching elements and is configured to asymmetrically control the duty cycles of the upper and lower switching elements based on a voltage level of the direct current supply voltage. In general, the duty cycle of the lower switching element is different than the duty cycle of the upper switching element. Additionally or alternatively, the duty controller is configured to determine and control the duty cycles of the upper and lower switching elements to adjust a direct current gain of a wireless energy transfer system that includes the wireless transmitter device.

公开(公告)号：US09948109B2

公开(公告)日：2018-04-17

申请号：US15161420

申请日：2016-05-23

Applicant: Apple Inc.

Inventor： Kisun Lee ,  Manisha P. Pandya ,  Shimon Elkayam

IPC: G06F1/00 ,  H02J3/38 ,  G06F1/26

CPC classification number: H02J3/385 ,  G06F1/263 ,  G06F1/266 ,  Y10T307/696

Abstract: The disclosed embodiments provide a power management system that supplies power to components in an electronic device. The power management system includes a system microcontroller (SMC) and a charger. During operation, the power management system accepts power from at least one of a power adapter and a solar panel. Next, the power management system supplies the power to components in the electronic device without using a converter circuit between the solar panel and the power management system.