Intelligent LED constant-current driving circuit

Abstract

The invention relates to an intelligent LED constant-current driving circuit, which comprises a power supply circuit. The power supply circuit supplies power to a control circuit; the control circuit is connected with a half-bridge power and protection circuit which is connected with an LED load; and the power supply circuit and the half-bridge power and protection circuit are respectively connected with a mains supply. The half-bridge power and protection circuit supplies the power to the LED load and the power supply circuit supplies the power to the control circuit, so that the interference of the input change of the load and the mains supply in the control circuit is reduced by adopting an independent power supply mode. The intelligent LED constant-current driving circuit supplies thepower to the load through the half-bridge power and protection circuit, has the maximum output power exceeding 100W, a large output current variation range and high efficiency and can adapt to high-power and large-scale load change.

Description

technical field [0001] The invention relates to a driving circuit, in particular to an intelligent LED constant current driving circuit. Background technique [0002] Due to the advantages of high luminous efficiency and high color purity of LED lights, LED lights are more and more used in the field of special lighting. Since the LED luminance is proportional to the current, the output of the LED luminous flux can be changed by adjusting the LED forward current. There are mainly four ways to adjust the luminous flux output of the existing LED constant current drive circuit: PWM pulse adjustment, thyristor phase cut adjustment, power tube linear amplification adjustment and current sampling switch adjustment. [0003] The first three adjustment methods have their own defects: first, the output current regulated by PWM pulse mode is intermittent, the luminous flux cannot be output smoothly and continuously, and the size of luminous flux cannot be correctly identified by the h...

AI Technical Summary

Problems solved by technology

[0003] The first three adjustment methods have their own defects: first, the output current regulated by PWM pulse mode is intermittent, the luminous flux cannot be output smoothly and continuously, and the size of luminous flux cannot be correctly identified by the high-speed optical sensor; second, the thyristor phase-cutting method Although the output current is adjusted continuously, the output current contains high power frequency ripple, and flickering problems often exist when adjusting in a wide current range; third, the power supply efficiency of the power tube linear amplification adjustment method is too low, and the power supply generates high heat and is reliable. Fourth, the current sampling switch adjustment method can continuously and accurately adjust the output current. However, because the existing drive circuit needs to consider the power supply efficiency, the current feedback signal is weak and susceptible to interference, and the output power is low. Realize continuous and smooth adjustment with high current accuracy in a large voltage and power range, and the existing adjustment method is easily interfered by the load power supply system when communicating with the host computer, and cannot be real-time and accurate according to the instructions of the host computer The adjusted output current of

Images