公开(公告)号：US10859603B1

公开(公告)日：2020-12-08

申请号：US16734017

申请日：2020-01-03

Applicant: Apple Inc.

Inventor： Erhan Ozalevli ,  Evaldo M. Miranda, Jr. ,  Behzad Mohtashemi

IPC: H03K17/082 ,  G01R15/14 ,  H03F3/45

Abstract: Embodiments relate to sensing a current provided by a power supply circuit. The current sensing circuit includes a sense transistor for sensing the current provided by a main transistor, a driver for controlling a bias provided to the sense transistor and the main transistor, and a sense resistor for converting the sensed current to a voltage value. Moreover, the current sensing circuit includes a controller that modifies at least one of: (a) a resistance of the main transistor by adjusting the bias voltage provided by the driver, (b) a gain ratio between a load current and a sensing current by adjusting a number of individual devices that are active in the sense transistor, and (c) a resistance of the sense resistor.

公开(公告)号：US11237191B2

公开(公告)日：2022-02-01

申请号：US17092158

申请日：2020-11-06

Applicant: Apple Inc.

Inventor： Erhan Ozalevli ,  Evaldo M. Miranda, Jr. ,  Behzad Mohtashemi

IPC: G01R15/14 ,  H03K17/082 ,  H03F3/45

Abstract: Embodiments relate to sensing a current provided by a power supply circuit. The current sensing circuit includes a sense transistor for sensing the current provided by a main transistor, a driver for controlling a bias provided to the sense transistor and the main transistor, and a sense resistor for converting the sensed current to a voltage value. Moreover, the current sensing circuit includes a controller that modifies at least one of: (a) a resistance of the main transistor by adjusting the bias voltage provided by the driver, (b) a gain ratio between a load current and a sensing current by adjusting a number of individual devices that are active in the sense transistor, and (c) a resistance of the sense resistor.

公开(公告)号：US11936352B2

公开(公告)日：2024-03-19

申请号：US17154939

申请日：2021-01-21

Applicant: Apple Inc.

Inventor： Erhan Ozalevli ,  Evaldo M. Miranda, Jr.

IPC: H03F3/45 ,  H03F3/387 ,  H03K5/24

CPC classification number: H03F3/45076 ,  H03F3/387 ,  H03K5/24 ,  H03F2200/375

Abstract: Embodiments relate to an amplifier circuit. The amplifier circuit includes multiple transistors. Each transistor is configured to receive an input signal and output an amplified signal. The amplifier circuit additionally includes a set of input chopper circuits and a set of output chopper circuits. Each output chopper circuit corresponds to one input chopper of the set of input choppers. Each input chopper circuit and its corresponding output chopper are controlled by one or more control signals from a set of control signals. Each input chopper circuit is configured to selectively connect each transistor of a transistor pair to a first input terminal or a second input terminal based on a value of the one or more control signals. Moreover, each output chopper circuit is configured to selectively connect each transistor of the transistor pair to a first output terminal or a second output terminal based on the value of the one or more control signals.

公开(公告)号：US10750595B1

公开(公告)日：2020-08-18

申请号：US16427865

申请日：2019-05-31

Applicant: Apple Inc.

Inventor： Erhan Ozalevli ,  Evaldo M. Miranda, Jr. ,  Mohammad J. Navabi-Shirazi

IPC: H05B45/37 ,  H02M1/08 ,  H03L7/183 ,  H05B45/00 ,  H05B45/44

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 control a light output level of the LED strings. The LED strings can be controlled by a mixed-mode LED driver that utilizes a PWM control signal over a first range of light output levels and an analog control signal over a second range of light output levels. Clock signals used for PWM control and for frequency-to-current or frequency-to-voltage conversion for analog control can both be generated from a phase locked loop (PLL).