Len Technology Limited

Volterra Semiconductor Corporation

Exar Corporation

Rohm Co., Ltd.

Jingquan Chen

Chuan Ni

Wei Lu

Zhenyu Zhao

Sombuddha Chakraborty

Paul H Choi

Jason Weinstein

Seth Marshall Kahn

Mark Hartman

Zdravko Lukic

Eric Iozsef

Joel Tang

Chen Li

Jeffrey D Mincey

The present application provides an LED control system, including an LED driver chip, a thermistor independent of the LED driver chip, and a matching resistor of the thermistor, wherein different thermistors correspond to different matching resistors; the LED driver chip and the matching resistor are configured to generate corresponding LED control targets according to different thermistors; wherein the upper and lower limits of the control targets are preset by the LED driver chip regardless of the thermistor; and the slope of the change of control target over the change of temperature is fitted with the slope of the change of thermistor resistance over the change of temperature, and the upper and lower limits of the control target remains the same for different choices of thermistors. The present application also provides a corresponding LED control method.

LED control method and system

The present application provides a controller for a switching power supply such as a DC-DC converter which provides an output voltage and an output current. The controller is configured to provide at least one control signal to operate the switching power supply to maintain the output voltage at a first reference voltage. The controller employs a load line compensator responsive to output current for adjusting the reference voltage employed by the compensator. The load line compensator employs one or either or both of a high pass filter or saturating element to provide a filtered/saturated value which is the value employed in adjusting the reference voltage.

Power supply controller with a load line compensator

The present application provides a power device driver including a detection module coupled to the power device and configured to detect the state of the power device; a driving module coupled to the detection module and the power device respectively and configured to detect the power of the detection module. As a result, the power device is regulated; wherein the detection module includes a fast detection sub-module configured to detect a state of the power device within a preset time period after the input signal of the driving device is invalid, and controlling the driving module to softly turn off the power device when there is overcurrent. The present application also provides a corresponding power device driving method and electric equipment.

Power device driver and method

The present application discloses a driving device for a power device, which includes a control circuitry configured to receive at least a system switching command and a feedback signal of a power device, and to generate a pull-up strength control signal or a pull-down strength control signal according to the received signals; and a pull-up array and/or a pull-down array, coupled between the control circuitry and the power device, and configured to provide a corresponding pull-up or pull-down strength for the power device according to the pull-up or pull-down strength control signal. The present application also discloses the corresponding electric appliance and power device driving method.

Power device driving device and driving method

This application discloses a driving device for a power device. It includes a detection module, coupled to the power device, configured to detect the overcurrent status of the power device; a drive module, respectively coupled to the detection module and the power device, configured to regulate the power device according to the detection result of the detection module; wherein, when the detection result is that the power device is in the first overcurrent state, the drive module is configured to cause the power device to enter the first protection mode that is softly turned off and does not respond to the system switching signal; when the detection result is that the power device is in the second overcurrent state, the drive module is configured to cause the power device to enter a second protection mode that is softly turned off but responds to a system switching signal; wherein the overcurrent degree in the first overcurrent state is higher than that of the second overcurrent state. This application also provides a corresponding power device driving method and electrical equipment.

Driving device and method of power device

This disclosure is related to the technical field of magnets, and in particular to a method for applying a coupled inductor to a DC-DC converter providing a DC current output, and based on the number of phases of the DC-DC converter, the coupled inductor is designed to have a corresponding number of windings, the windings are reversely coupled to cancel out the magnetizing fields to avoid flux saturation of the magnet material under high current excitation, and the coupled inductor has air gaps, the leakage flux in the air gap induced by each winding is in the same direction, the leakage magnetic flux is used to achieve the filtering of the output current.

Coupled inductor in a DC-DC converter

A method for controlling a DC-to-DC converter includes: (a) regulating a magnitude of an output voltage of the DC-to-DC converter according to a magnitude of a reference voltage; (b) in response to a command to enter the unregulated operating mode, allowing the magnitude of the output voltage to fall; and (c) adjusting the magnitude of the reference voltage to track the magnitude of the output voltage. A controller for a DC-to-DC converter includes reference and switching modules. The reference module generates a reference voltage, such that: (a) a magnitude of the reference voltage is fixed, in a regulated operating mode, and (b) the magnitude of the reference voltage tracks a magnitude of an output voltage of the DC-to-DC converter, in the unregulated operating mode. The switching module controls a power stage of the DC-to-DC converter to regulate the magnitude of the output voltage, in the regulated operating mode.

Systems and methods for controlling DC-to-DC converters including unregulated operating modes

Disclosed are devices, apparatus, circuitry, components, mechanisms, modules, systems, and methods for virtual output voltage sensing for feed-forward control of a voltage regulator. A buffer has an input coupled to sense a monitored signal indicating a duty cycle of switch circuitry coupled to an output filter of the voltage regulator. The buffer is configured to provide at an output, responsive to the monitored signal, a buffer output signal having a high reference voltage for a high side on time and a low reference voltage for a low side on time of the switch circuitry. A filter is coupled to receive and filter the buffer output signal to provide a feed-forward signal indicating the output voltage of the voltage regulator. Control circuitry is configured to control the switching of the switch circuitry responsive to the feed-forward signal.

Virtual output voltage sensing for feed-forward control of a voltage regulator

A digital pulse controller uses digital logic to send pulses to a high side and low side switches of a switch-mode power supply converter. The digital logic uses a pulse frequency mode which includes a frequency targeting mode and an ultrasonic mode. The frequency targeting mode dynamically adjusts the size of the pulses in order to achieve a switching frequency within a desired band. The ultrasonic mode is switched into when the frequency of the pulses are at or below a threshold and the time of the pulses reaches a minimum threshold.

Digital pulse-frequency modulation controller for switch-mode power supplies with frequency targeting and ultrasonic modes

A controller produces high-side and low-side control signals. The high and low-side signals are used to switch high-side and low-side transistors in the power stage to control the voltage across the power stage output capacitor of the power stage. A boost feedback charge pump receives the low or high-side signal to increase the charge on a charge pump output capacitor. The controller is configured to send Pulse Frequency Modulation (PFM) high and low-side signals that control the voltage on the power stage output capacitor and charge the charge pump output capacitor. The controller is also configured to send boost feedback (BFB) high and low-side signals that charge the boost feedback capacitor, but are designed to not significantly change the charge on the power stage output capacitor.

Digital boost feedback voltage controller for switch-mode power supplies using pulse-frequency modulation

A multichannel digital pulse width modulator/digital pulse frequency modulator uses a single ring oscillator that is shared by multiple channels. The ring oscillator has taps that can be used for least significant bit (LSB) precision of the generated PWM signal. The ring oscillator also produces a ring clock that is used to synchronize logic in the channels. Since the logic in the channels are synchronized by the ring clock, the channels can each independently produce different frequency PWM (or PFM) signals and still share the same ring oscillator.

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San Jose, CA, United States of America

Jingquan Chen