LED power challenge
As a new type of electric light source, LED has obvious advantages in the production of large-scale luminous three-dimensional characters and illuminating signs, with low control voltage, low cost and high reliability. Although LED products have a growing trend in the domestic and international markets, LED lighting is an emerging industry after all, and it has not been widely popularized. Therefore, LED driving power is inevitably challenging in all aspects: First, due to the positive direction of LED The voltage will change with current and temperature, and its "color point" will drift with current and temperature. In order to ensure the normal operation of the LED, its driver is required to change the input condition and forward voltage. Limit the current. Secondly, if LED dimming is required, pulse width modulation dimming technology is usually used. The typical PWM frequency is 1~3kHz. Finally, the power handling capability of the LED driver circuit must be sufficient, and the function is strong, and can withstand various fault conditions. ,Easy to implement.
The scheme described in this paper adopts the chip of Panasonic Panasonic MIP553 built-in PFC dimmable LED driver circuit, which is combined with external non-isolated bottom edge chopper circuit as the basic circuit structure, and outputs stable current to meet the needs of LED operation. At the same time, a protection circuit is designed to protect the load. The experimental results show that the controller chip can work stably and can achieve a constant voltage output of 27V and a constant current output of 350mA.
The basic working principle of LED power supply
The BUCK converter and IPD control are used to realize the switching power supply, and output constant current and voltage to drive the LED lamp. The overall block diagram of the circuit is shown in Figure 1.
The main circuit part is followed by a filter after the mains supply. Its function is to filter out the higher harmonics in the power supply and the surge in the power supply, so that the control circuit is less interfered by the power supply. The input rectification part adopts an integrated rectifier bridge. The unidirectional conduction characteristic of the diode converts the alternating current whose level is floating up and down at zero to a unidirectional pulsating direct current, and then outputs a direct current voltage under the action of the filter capacitor and the inductor. After the adjustment and control of the MIP553 and BUCK circuits, the voltage for the LEDs is output.
MAINTEX is a professional development and production of Barrier gate motor & Boom barrier motor manufacturer and supplier in China. Welcome to contact us for boom barrier motor Price of your demands.
Features of our barrier motor are 30V Low-voltage Brushless DC Motor, Long Life and Strong Anti-interference.
If you want barrier gate motor , Boom Barrier motor or Other Products , please contact us to customize for you.
Auto Gate Motor
barrier gate motor,boom barrier motor
Shenzhen Maintex Intelligent Control Co., Ltd. , https://www.maintexmotor.com