Qualcomm Incorporated

Sandeep Chaman Dhar

Todd Robert Sutton

Troy L Stockstad

Narendra Singh Mehta

Xinli Peng

Szepo Robert Hung

Ruben Manuel Velarde

Hengzhou Ding

Hua Guan

Chunlei Shi

Chris M Rosolowski

Joshua Zazzera

Raymond Rosik

Nathaniel Jay Tobias Salazar

Qadeer A Khan

Raymond Keith Rosik

A circuit may include a control loop to regulate an output of the circuit and a headroom sensing circuit to produce a headroom sensing signal indicative of a headroom voltage of the circuit. The control loop may have a response characteristic that is set based on the headroom signal received from the headroom sensing circuit.

Adaptive stability control for a driver circuit

Certain aspects relate to systems and techniques for color temperature analysis and matching. For example, three or more camera flash LEDs of different output colors can be used to match any of a range of ambient color temperatures in a non-linear space on the black body curve. The scene color temperature can be analyzed in a preliminary image by determining actual sensor R/G and B/G ratios, enabling more accurate matching of foreground flash lighting to background lighting by the reference illuminant for subsequent white balance processing. The current provided to, and therefore brightness emitted from, each LED can be individually controlled based on the determined sensor response to provide a dynamic and adaptive mix of the output colors of the LEDs.

Multi-LED camera flash for color temperature matching

The present disclosure includes circuits and methods for driving resonant actuators. In one embodiment, a drive signal is applied to an actuator during a portion of a plurality of half cycles of a period of the drive signal. The actuator has a resonant frequency and may vibrate in response to the drive signal. An induced voltage is generated on terminals of the actuator in response to the vibration. A detection circuit may detect when the induced voltage on the actuator crosses a threshold after the drive signal is turned off. The drive signal may be triggered based on when the induced voltage crosses the threshold to align a frequency and phase of the drive signal with the resonant frequency and a phase of the actuator.

Circuits and methods for driving resonant actuators

Techniques for autonomous thermal management of a power-management integrated circuit (PMIC). In an exemplary embodiment, an embedded microcontroller is provided on the PMIC to store instructions for implementing a thermal controller. The thermal controller may manage in real-time the current scaling factors of a plurality of modules coupled to corresponding off-chip power entities. The thermal controller may include registers that are programmable by an off-chip entity such as a microprocessor to specify parameters such as module priorities and a minimum current scaling factor for each module. Power entities that may be controlled by the autonomous thermal controller include, e.g., a battery charger, and/or one or more user-interface entities such as a back light display driver, a flash LED driver, or an audio amplifier.

Autonomous thermal controller for power management IC

An electronic device is described. The electronic device includes a first port. The electronic device also includes a second port. The electronic device further includes a multiphase charger. The multiphase charger includes a first buck. The multiphase charger also includes a second buck. The multiphase charger further includes a first port switch. The multiphase charger also includes a second port switch. The multiphase charger further includes a reverse boost switch. The multiphase charger also includes a multiphase switch.

Multiphase charger

A method and apparatus for a boost converter topology for low battery voltage support. In the method, an input voltage is boosted by closing first through third switches and then opening a fourth switch to charge a capacitor. The first and second switches are then opened. The voltage is then doubled by closing the third and fourth switches to discharge the first capacitor into a second capacitor and charging a third capacitor. A further embodiment provides an additional method for selectively boosting an input voltage to an electronic device. The method first characterizes the efficiency of a circuit, and then determines a crossover point for a ratio of output voltage to input voltage, and then enabling or disabling a voltage boost converter based on the crossover point.

Boost converter topology for high efficiency and low battery voltage support

A circuit for driving a load may include a control loop having a response characteristic. A headroom signal indicative of the headroom voltage of the circuit may set one or more parameters of the response characteristic. A load sign indicative of electrical loading on the circuit may further set the response characteristic.

A method and apparatus for optimizing a light emitting diode (LED) operation range is provided. The method comprises the steps of: turning on at least one LED; and then measuring an anode voltage of the at least one LED; then measuring a cathode voltage of the at least one LED. Once the measurements are completed, a forward voltage of the at least one LED is calculated. After the calculation, the at least one LED is turned off and a power multiplexer switch threshold is set for that LED based on the measured anode and cathode voltages.

Growing community of inventors

San Diego, CA, United States of America

Sandeep Chaman Dhar