US 11,895,749 B2 · Light emitting diode (LED) drive method and circuit, and LED lighting device

Abstract

A light-emitting diode (LED) drive method, an LED drive circuit, and an LED lighting device are provided. The method includes: setting preset values of a maximum on-time parameter and a current limit parameter, where the preset values are in at least two sets; selecting a set of the preset values of the maximum on-time parameter and the current limit parameter after a value of a voltage signal on a direct current (DC) bus is detected; controlling a drive current flowing through an LED load based on a selected maximum on-time parameter and a selected current limit parameter. The maximum on-time parameter and the current limit parameter of the system can be adaptively adjusted according to an input voltage, so that the system can have a preferred dimming schedule and dimming depth while realizing a constant current in a wider input voltage range.

Claims20

Dependent claims

A light-emitting diode (LED) drive method, comprising:

setting preset values of a maximum on-time parameter and a current limit parameter, wherein the preset values are in at least two sets;
selecting a set of the preset values of the maximum on-time parameter and the current limit parameter after a value of a voltage signal on a direct current (DC) bus is obtained;
and
controlling a drive current flowing through an LED load based on a selected maximum on-time parameter and a selected current limit parameter.

1 more element

An LED drive circuit, comprising:

a dimmer, wherein the dimmer is configured to cut a phase of an input AC power supply to output a first voltage signal;
a rectifying circuit, wherein the rectifying circuit is configured to rectify the first voltage signal to output a second voltage signal to a DC bus;
a controller, wherein the controller is configured to generate a control signal according to a preset maximum on-time parameter and a preset current limit parameter;
a power conversion circuit, wherein the power conversion circuit is configured to control a drive current flowing through an LED load based on the second voltage signal and the control signal;
and
a parameter regulating circuit, wherein the parameter regulating circuit is configured to select preset values of the maximum on-time parameter and the current limit parameter according to the second voltage signal, wherein the preset values are input to the controller.

3 more elements

Dependencies are inferred from the claim text.

Light emitting diode (LED) drive method and circuit, and LED lighting device

Life of this patent

Light emitting diode (LED) drive method and circuit, and LED lighting device

Life of this patent

Abstract

Claims20