Linear Technology Corporation

Supertex, Inc.

Analog Devices,inc.

Trinity Axis Inc.

Wei Gu

David Schie

Alexander Mednik

James Nguyen

Michael George Negrete

Siyuan Chen

Min Hao Chen

Dan Harden

Jeremiah Divyan David

David D Davidar

Sang Ton Ngo

Xugang Ke

Khai Minh Le

Arunkumar G

Loganathan B

Vignesh Kumar V

Cole Derby

Larry Kerenyi

Zhizheng Liu

Zhen Li

Wen Chuen Liu

Yuchen Yang

Periasamy G

Carlos Terminel

Dinesh Raj

Dispensing machine

An apparatus including a bidirectional power converter circuit. The power converter circuit includes a primary circuit side including a plurality of primary switches, an isolation transformer, and a secondary circuit side separated from the primary circuit side by the isolation transformer. The secondary circuit side includes an inductor, a rectifier circuit coupled to the inductor and configured to receive energy from the primary circuit side and provide energy to the primary circuit side, and a clamp circuit coupled to the inductor and configured to provide a reset voltage to the inductor that prevents inductor current runaway.

Active-clamp current-fed push-pull converter for bidirectional power transfer

A UHV-LV interface circuit that is capable of the following, among other things: 1) starting up a primary controller of a power converter circuit with a precisely controlled startup charging profile; 2) performing pulse-based line-voltage sensing with reduced power and improved sensing accuracy; and 3) discharging a capacitor, e.g., class-X2 capacitor, with a stable supply voltage for the controller. The UHV-LV interface circuit can use a single UHV device, such as a single depletion-mode transistor, e.g., field-effect transistor (FET).

High-voltage to low-voltage interface in power converter circuit

A flyback controller generates a switching signal for controlling delivery of current into a primary winding of a transformer in a flyback converter. The controller may include an output current monitoring circuit configured to generate a signal representative of an average output current in a secondary winding of the transformer based on a peak input current in the primary winding and a duty cycle of current in the secondary winding. The flyback controller may generate a switching signal that causes a chopped AC voltage from a dimmer control to be converted by the flyback converter into an average output current from a secondary winding of the transformer that is DC isolated from the chopped AC voltage and that varies as a function of the setting of the dimmer control. The flyback controller may not utilize a signal from an opto-isolator.

Dimmer-controlled LEDs using flyback converter with high power factor

An apparatus and method for dimming a light emitting diode (LED) driver. The apparatus includes a triode alternating current (TRIAC) dimmer and an LED driver receiving an input voltage from an output of the TRIAC dimmer so that the state of the LED driver is controlled by the TRIAC dimmer. The LED driver includes an active damping circuit configured for damping, upon detecting a rising edge of a bridge rectified input voltage, resonance caused by the TRIAC dimmer and the LED driver for a fixed period of time.

Method and system for dimming an offline LED driver

A flyback controller may receive a chopped and rectified AC voltage from a dimmer control, each cycle of which may have a controllable off period that is substantially attenuated but not always zero due to leakage of the dimmer control, and a controllable on period that substantially tracks the AC voltage. The flyback controller may include a control circuit configured to generate a switching signal based on the signal from the dimmer input. The switching signal may controllably oscillate between its on and off states during the on periods of the chopped and rectified AC voltage so as to controllably regulate current that is delivered by a secondary winding of a transformer in a flyback converter. The switching signal may be in the on state during the off periods of the chopped and rectified AC voltage, thereby preventing a voltage build up from the dimmer control leakage.

Dimmer control leakage pull down using main power device in flyback converter

A switching power converter and method of controlling an output voltage thereof using predictive sensing of magnetic flux provides a low-cost switching power converter via primary-side control using a primary-side winding. An integrator generates a voltage that represents flux within a magnetic element by integrating a primary-side winding voltage. A detection circuit detects the end of a half-cycle of post-conduction resonance that occurs in the power magnetic element subsequent to zero energy level in the power magnetic element. The integrator voltage is stored at the end of the half-cycle and is used to determine a sampling point prior to or equal to the start of post-conduction resonance in a subsequent switching cycle of the power converter. The primary-side winding voltage is then sampled at the sampling point, providing an indication of the output voltage of the power converter by which the output voltage of the converter can be controlled.

Switching power converter and method of controlling output voltage thereof using predictive sensing of magnetic flux

A switch state controller generating a pulse train is used in a power converter utilizing a plurality of converter stages all simultaneously controlled by a single switch controlled by said pulse train. On time of the pulse train is controlled according to an input or interim node characteristic of the supply and period is controlled by a characteristic of the output of the converter. This allows development of AC-to-DC converters, including power-factor-correction converters, and DC to DC converters with high conversion ratio with minimal parts count & high reliability.

Optimal control of wide conversion ratio switching converters

AC/DC cascaded power converters having high DC conversion ratio and improved AC line harmonics provide low input harmonic currents, high power factor and efficient operation for low voltage DC outputs when coupled directly to a source of unfiltered rectified AC voltage. The power converter incorporates an intermediate storage element that provides most or all of the energy storage capacitance within the power converter and a blocking device that enables continuous energy transfer from AC line to output to achieve unity power factor and regulated output while maintaining low AC input current ripple.

AC/DC cascaded power converters having high DC conversion ratio and improved AC line harmonics

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San Jose, CA, United States of America

Wei Gu