Linear constant-current LED light circuit

Abstract

A linear constant-current LED light circuit that can automatically adapt to a change of an input voltage according to changes of a quantity of dedicated constant-current circuits and a quantity of LEDs in series, so that a total voltage of the LEDs is always close to the input voltage, thereby reducing a voltage drop of a constant-current transistor and reducing power loss of the constant-current transistor, so as to achieve energy saving. The dedicated constant-current circuits make the LEDs work in a rated current range, without generating overcurrent to cause damage, and a progressive decrease of a resistance of n stage dedicated constant-current circuits is set to implement a progressive increase of currents of the n stage dedicated constant-current circuits, so that a working current of the circuit can follow the input voltage. Therefore, the circuit has a relatively high power factor, relatively low harmonic distortion, and good electrical performance.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority to Chinese application number 201810651967.4, filed Jun. 22, 2018, with a title of LINEAR CONSTANT-CURRENT LED LIGHT CIRCUIT. The above-mentioned patent application is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION1. Field of Invention[0002]The present invention relates to the field of LED control technologies, and in particular, to a linear constant-current LED light circuit.2. Background of Related Art[0003]At present, there are many LED (Light Emitting Diode, light emitting diode) lights using a linear constant-current scheme. In the linear constant-current scheme, a switch power supply is omitted, and an LED light has a longer service life and a simple structure, and can be integrated with LED light beads to be assembled into a light panel. The linear constant-current scheme is naturally compatible with a silicon-controlled light dimmer to implement silicon-controlled ligh...

AI Technical Summary

Benefits of technology

The present invention provides a linear constant-current LED light circuit that has several technical effects. Firstly, it adapts to changes in input voltage, reducing power loss and energy usage. Secondly, it uses dedicated constant-current circuits to prevent damage and ensure the LEDs work within a safe range. Lastly, a progressive decrease in resistance ensures the circuit has a high power factor, low harmonic distortion, and good electrical performance. Increasing the quantity of LEDs and dedicated constant-current circuits further improves the efficiency and power factor, while reducing harmonic distortion.

Problems solved by technology

However, there is no unified interface standard for these external light dimming manners and linear constant-current LED lights.

A circuit is relatively complex, and light dimming cannot be performed by using a constant-current integrated circuit scheme.

For a multistage linear constant-current scheme that achieves relatively high performance, it is more difficult to implement external light dimming with good performance, and there is rarely a mature scheme.

It can be learned that a general linear constant-current scheme used by an existing linear constant-current LED light, there are generally problems, such as poor performance, low efficiency, low luminous efficiency, low power factor, and high harmonics.

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