Multifunctional LED light modulation interface circuit

Abstract

A multifunctional LED light modulation interface circuit includes a power supply circuit, a light modulation zone lower limit setting circuit, a filter circuit, a subtracter, a light modulation zone upper limit setting circuit, an amplitude limiter and a weighted addition circuit. The power supply circuit and the filter circuit are connected on the input end of an interface circuit. The power supply circuit supplies DC voltage to a resistance-variable light modulator and the filter circuit filters control signals when pulse-width modulation control signals are input, and the output of the filter circuit is subtracted by voltage of the light modulation zone lower limit setting circuit in the subtracter. After the lowest level is limited, the output of the subtracter and the light modulation zone upper limit setting voltage set the highest level in an amplitude limiting circuit. The weighted addition circuit output weighted linear change and light modulation referential voltage with high and low level limits according to the requirement of a modulated light brightness variation scope. The interface circuit is compatible with a plurality of light modulation control means. The multifunctional LED light modulation interface circuit is low in cost, flexible in light modulation zone setting, and excellent in linearity.

Description

technical field [0001] The invention relates to dimming control of a dimmable LED driver, in particular to a multifunctional LED dimming interface circuit. Background technique [0002] In recent years, LED lighting has shown a rapid development trend due to its advantages such as high energy efficiency, long life, small size, and environmental protection. Especially in the field of dimming applications, it also has continuously adjustable brightness, fast dimming speed, dimming The advantages of low light depth, high dimming precision and easy digital control have been widely used. [0003] Since the volt-ampere characteristics of LEDs present nonlinear and negative temperature characteristics, constant current driving is generally used in LED lighting. By continuously changing the magnitude of the LED current, the purpose of dimming can be achieved. This dimming method is also called analog dimming. During analog dimming, the working current of the LED is continuous and ...

AI Technical Summary

Problems solved by technology

At present, it is difficult for the dimming interface circuit to be compatible with multiple dimming control signals on the same interface, and users are often required to connect to different ports according to the type of dimming control signals, which brings troubles to terminal application customers.

In addition, in the existing implementation schemes, single-chip microcomputers are mostly used to realize the function of the dimming interface circuit. The design is simple, but the cost is high, and the development involves software and hardware debugging, and the development cycle is long

Although some solutions use discrete components, they do not support the flexible setting of the dimming range, and the linearity is not good.

Images