Maximum brightness enhancement module, thyristor dimming led drive circuit and system

Abstract

The invention discloses a silicon controlled light-dimmer LED driving circuit. A drain electrode of a second MOS transistor is connected with a source electrode of a power switch MOS transistor, a source electrode of the second MOS transistor is connected with a sampling resistor, the output end of a largest brightness lifting module is electrically connected with the first input end of a peak value current comparator and a feedforward resistor through a drain electrode of a first MOS transistor in the largest brightness lifting module, current signals output by the first MOS transistor pass through the feedforward resistor to generate direct-current bias voltages, the first input end of the peak value current comparator is electrically connected with the sampling resistor through the feedforward resistor, the second input end of the peak value current comparator is electrically connected with the output end of a reference voltage source, the output end of the peak value current comparator is coupled to a grid electrode of the second MOS transistor, and the peak value current comparator is used for comparing the sum of the voltage amplitude of the feedforward resistor and the voltage amplitude of the sampling resistor with a voltage threshold value of the reference voltage source, and controls the second MOS transistor to be switched on and off. When a driving circuit is connected with a silicon controlled light dimmer, the largest current is improved through the largest brightness lifting module.

Description

technical field [0001] The invention relates to the field of LED driving, in particular to a thyristor dimming LED driving circuit and system with maximum brightness improvement. Background technique [0002] see figure 1 , a simplified schematic diagram of a prior art thyristor dimming LED drive circuit. Such as figure 1 As shown, an input AC power source 101 is connected in series with a thyristor dimmer 102 , and then connected to two input terminals of a rectifier bridge 103 . The rectifier bridge 103 rectifies the alternating current and filters it through the capacitor C1 to generate a rectified sinusoidal voltage. The resistor R4 and the capacitor C2 generate a low-voltage direct current to activate the control chip 104 . The transformer T1 has three windings, including a primary winding T11 connected between the capacitor C1 and the drain of the power switch MOS transistor M1; a secondary winding T12 connected between the freewheeling diode D1 and the secondary o...

AI Technical Summary

Problems solved by technology

[0005] 2) The power consumption of the bleeder resistor R1 and the bleeder switch M2 is high, which leads to loss of LED drive circuit efficiency and high temperature rise, which reduces system reliability

Images