LED linear constant current drive circuit with adaptive wide voltage range

Abstract

The invention discloses an LED linear constant current drive circuit with an adaptive wide voltage range, comprising a rectifier bridge (1) which rectifies the sinusoidal voltage waveform in full waveand is connected with a filter circuit (2) and a high voltage stabilization and reduction circuit (5) through wires, the filter circuit (2) which is used for carrying out filtering to convert a fullwave pulsating voltage output from the rectifier bridge into a direct voltage and is connected with a constant current source circuit (3) through a wire, the constant current source circuit (3) whichis used for limiting the current flowing through the load LED and providing a constant current power supply for LED lamps and is connected with a switching array circuit (4) through a wire, the switching array circuit (4) which is used for switching an LED lamp string between the series and parallel connection modes based on the switching characteristic of the LDMOS tube when the external voltagechanges, and the high voltage stabilization and reduction circuit (5) which provides a working voltage for low-voltage modules. The technical problem that waste is caused due to inadequate utilizationof LED in the prior art is solved.

Description

technical field [0001] The invention belongs to the technical field of integrated circuits, and in particular relates to an adaptive wide voltage range LED linear constant current drive circuit. Background technique [0002] As the fourth-generation light source, LED has high light efficiency, long life, and no pollution, and has all the characteristics of high-efficiency lighting. As a key component of LED lamps, LED drive power plays a vital role in the performance and life of lamps. In recent years, the linear constant current drive power supply of LED has developed very rapidly, from linear constant current drive power supply to high voltage linear constant current drive power supply, and further developed to the current segmented linear constant current drive power supply. At present, there are two mainstream segmental linear constant current drive power supplies. One uses the voltage clamping function of the LED itself to segment the LED array. When the voltage fluctu...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to provide an adaptive wide voltage range LED linear constant current drive circuit to solve the voltage clamping of the LED segmented linear constant current drive power supply in the prior art when the LED is forward-conducting. The function is to segment the LED array. When the voltage fluctuates after rectification, the number of LEDs connected to the circuit also changes accordingly, and the voltage at both ends of the LED light string is basically consistent with the input voltage; the other is to use the forward conduction of the LED. The characteristic of reverse cut-off, 4 LEDs form a rectifier bridge structure, when the grid voltage passes through the LED rectifier bridge, it directly supplies power to the two LEDs; the existing LEDs are not fully utilized, resulting in technical problems such as waste

Images