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公开(公告)号：US09893628B2
公开(公告)日：2018-02-13
申请号：US15064395
申请日：2016-03-08
Applicant: Apple Inc.
Inventor： Zaohong Yang , Behzad Mohtashemi
CPC classification number: H02M3/33507 , H02M3/33576 , H02M3/33592 , H02M2001/0067 , H02M2001/007 , H02M2001/0074 , H02M2001/0077
Abstract: This disclosure relates to power converters that are capable of providing smooth transitions between multiple output voltage levels. The converter's output may need to be changed from, e.g., 5V to 12V, 15V, or 20V—based on the charging device's request. By using improved power converter designs comprising both a flyback converter circuit and variable-frequency buck converter circuit that may each be selectively coupled to an output load, a more smooth, e.g., monotonous, transition between output voltage levels may be achieved. In particular, by varying the switching frequency of the buck converter in a controlled way, the output voltage of the power converter may rise monotonically during the transition between output voltage levels. According to some embodiments, once the output of the buck converter has reached its maximum value, the buck converter may be disabled, and the flyback converter may be enabled to begin supplying the output voltage to the load.
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公开(公告)号：US09673701B2
公开(公告)日：2017-06-06
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.
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公开(公告)号：US20200105185A1
公开(公告)日：2020-04-02
申请号：US16418882
申请日：2019-05-21
Applicant: Apple Inc.
Inventor： Jingdong Chen , Asif Hussain , Mohammad J. Navabi-Shirazi , Behzad Mohtashemi , Yanhui Xie , JY Ryoo , Ming Gu
Abstract: A display may have an array of pixels illuminated using a backlight unit. The backlight unit may include multiple strings of light-emitting diodes (LEDs) and a boost converter for providing an output voltage to the multiple LED strings. The boost converter may have a single-phase single-switch, single-phase multi-switch, and/or multi-phase multi-switch configuration, where the switches are turned off when the peak current is reached. When transitioning from a single phase to a dual phase operation, the second (slave) phase current may be slowly ramped up. When transition from the dual phase to the single phase operation, the output voltage may be elevated while slowing ramping down the slave phase current. The boost converter may include a current detection circuit for adjusting the peak current of each phase to balance the average current levels. The boost converter may also include an in-rush current controller configured to sense a short fault.
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公开(公告)号：US10512130B1
公开(公告)日：2019-12-17
申请号：US16265401
申请日：2019-02-01
Applicant: Apple Inc.
Inventor： Erhan Ozalevli , Behzad Mohtashemi
Abstract: LED backlight circuits for a display and methods for operating the circuits are disclosed. The LED backlight circuit includes a set of drivers and a set of LED strings. A driver can be capable of coupling to any of the LED strings at a given time. Examples of the disclosure can include different configurations of drivers. In some instances, the driver may include an auxiliary transistor that allows the driver to settle before being switched to control a respective LED string. In some examples, the driver can include switches and an idle transistor that can be operated such that a low current path through the driver can exist when the driver is not coupled to a LED string.
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公开(公告)号：US10148178B2
公开(公告)日：2018-12-04
申请号：US15646035
申请日：2017-07-10
Applicant: Apple Inc.
Inventor： InHwan Oh , Manisha P. Pandya , Behzad Mohtashemi
Abstract: A power converter includes a buck converter with a low-side switch. During a discharge mode, current passes through the low-side switch to form a current loop. The low-side switch is typically closed synchronously with the opening of a high-side switch coupled to an input voltage level to the buck converter. The power converter also includes a high-side controller and a low-side controller, which together are configured to adjust the timing of the operation mode of the high-side controller between a storage mode and the discharge mode.
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Patent Agency Ranking
16.发明申请公开(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
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
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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。
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18.发明授权公开(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.
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公开(公告)号：US10714028B2
公开(公告)日：2020-07-14
申请号：US16418882
申请日：2019-05-21
Applicant: Apple Inc.
Inventor： Jingdong Chen , Asif Hussain , Mohammad J. Navabi-Shirazi , Behzad Mohtashemi , Yanhui Xie , Jy Ryoo , Ming Gu
Abstract: A display may have an array of pixels illuminated using a backlight unit. The backlight unit may include multiple strings of light-emitting diodes (LEDs) and a boost converter for providing an output voltage to the multiple LED strings. The boost converter may have a single-phase single-switch, single-phase multi-switch, and/or multi-phase multi-switch configuration, where the switches are turned off when the peak current is reached. When transitioning from a single phase to a dual phase operation, the second (slave) phase current may be slowly ramped up. When transition from the dual phase to the single phase operation, the output voltage may be elevated while slowing ramping down the slave phase current. The boost converter may include a current detection circuit for adjusting the peak current of each phase to balance the average current levels. The boost converter may also include an in-rush current controller configured to sense a short fault.
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公开(公告)号：US10075095B2
公开(公告)日：2018-09-11
申请号：US15148245
申请日：2016-05-06
Applicant: Apple Inc.
Inventor： Asif Hussain , Behzad Mohtashemi , Manisha P. Pandya , Mohammad J. Navabi-Shirazi
CPC classification number: H02M7/537 , H02M1/08 , H02M3/158 , H02M2001/0009 , H02M2001/0058 , Y02B70/1425 , Y02B70/1483 , Y02B70/1491
Abstract: Various systems, apparatuses, and methods are disclosed herein, which provide a new power conversion topology for isolated systems that does not include a transformer. Embodiments of the inventive systems comprise: a switching system utilizing high voltage, low leakage switches, e.g., Silicon Carbide (SiC) MOS-FETs; a power source; an inductor and a capacitor operating as a link stage resonant LC circuit; and a load. The switching system may be configured to be controlled in a synchronized ‘four phase’ control loop process, wherein the input switches are prevented from being closed at the same time as the output switches, thereby providing electrical isolation between the input power source and the load—without the use of a transformer. 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, displays, and computers.
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