Cypress Semiconductor Corporation

Google Inc.

Other

Kedar Godbole

Hariom Rai

Doug Vargha

Anita X Meng

Doung Vargha

Douglas Vargha

Chi Wang Ng

A circuit in accordance with one embodiment of the invention can include a light emitting diode (LED) assembly comprising a plurality of LED channels that are controlled independently with a switch mode driver. The circuit also includes N+1 wires coupled to said LED assembly, where N is equal to the number of said plurality of LED channels of said LED assembly.

Light emitting diode assembly

A circuit coupled to a light emitting diode (LED) driver circuit is described. The circuit is operative to control functionality of the LED driver circuit based on a firing angle from a power switch.

System and method for controlling a light emitting diode fixture

An adaptive algorithm running on a processing device receives a temperature value that represents a temperature at a gate terminal of a transistor. The adaptive algorithm, determines a drive strength value that represents a drive strength for a signal based on the temperature value. A signal with the determined drive strength is applied to the gate terminal of the transistor.

Adaptive gate driver strength control

An embodiment of the present invention is directed to a method and circuit to control light emitting diode (LED) output. The method includes receiving a line voltage signal which powers a lighting circuit comprising an LED and determining an adjustment of a threshold based on a variation of the line voltage signal and/or a controller delay or other practical controller limitation or imperfection. The method further includes dynamically adjusting a threshold or other reference of a controller which controls a switch of said lighting circuit for compensating for line variations to maintain a substantially uniform LED current.

Compensation method and circuit for line rejection enhancement

One embodiment in accordance with the invention can include a circuit for controlling a light emitting diode (LED) lighting fixture via a power line. The circuit can include a power switch coupled to the power line and is for outputting a firing angle. Additionally, the circuit can include a control circuit coupled to the power switch and is for implementing firing angle control of the power switch. Furthermore, the circuit can include a translator coupled to receive the firing angle and for mapping the firing angle to a function of the LED lighting fixture.

A processing circuit may include a command source that receives at least one feature input control signal for a lighting fixture; and an adaptive filtering mechanism that generates a filtered control signal in response to the input control signal, wherein the adaptive filtering mechanism varies a filter function in response to at least a temporal state of the input control signal.

Adaptive filter for lighting assembly control signals

A circuit in accordance with one embodiment of the invention can include an LED drive circuit that may isolate a sense circuit from a supply voltage in a passive mode, and maintain a predetermined voltage difference between the sense circuit and the supply voltage in an operational mode.

Lighting assembly, circuits and methods

A driver circuit, and light emitting system and method are provided. The driver circuit includes possibly a controller and a phase detector coupled to produce an intermittent output proportional to a value of an input relative to upper and lower threshold values, and a difference between the input signal, which is the intermittent output signal, and a reference value. The light emitting system can include a switch and at least one light emitting device coupled to the switch. The driver circuit can be coupled to forward the intermittent output signal to the switch that is active in proportion to current level through the light emitting device, rising and falling between the modifiable upper and lower threshold values.

Phase control for hysteretic controller

Disclosed herein is an apparatus and method to control a current through one or more Light Emitting Diode (LED) circuits, wherein a control command compensation unit generates a compensation function to offset errors in the LED circuit by modifying a temporal density modulation function.

Current compensation scheme for LED current control

A circuit may include a switch mode power converter that intermittently enables a current path in response to a switch control signal; a duty cycle measurement circuit that generates a duty cycle value corresponding to a duty cycle of the switch control signal; and an evaluation circuit that activates a failure indication in response to the duty cycle value being outside of at least one limit.

Lighting element failure detection devices and methods for power switching based systems

Controlling a light emitting diode fixture

A light emitting driver circuit, system, and method are provided. The driver circuit system and method can be implemented in various ways. An embodiment includes a bypass circuit which diverts current from the LEDs whenever a switch coupled to the LEDs incurs residual current when turned off. In an additional or alternative embodiment, the residual current can be sensed and the amount of residual current used to trigger fetching of a compensation value. That compensation value can change a dimming function forwarded to the switch in order to compensate for, offset, or substantially eliminate the residual current through that switch.

Growing community of inventors

San Jose, CA, United States of America

Kedar Godbole