Fluorescent tubes are widely used in daily life, supermarkets, schools, office cities, subways, etc., but in public places that can be seen, you can see the use of fluorescent lamps! The energy-saving and energy-saving performance of LED fluorescent lamps has been widely recognized after a long period of publicity. However, many of the LED fluorescent tubes that have been bought at high prices are now in the same situation as cheap energy-saving lamps: energy saving. money! Moreover, it is a lot of waste of money. How to make the LED service life and brightness reach the standard of satisfactory use is a very meaningful topic! LED fluorescent tubes should maintain long life and high brightness. The problems to be solved are: power supply, LED light source, heat dissipation and safety.

a power source

The primary requirement of the power supply is high efficiency and high efficiency. If the heat is low, the stability will be high. Generally, there are two schemes of isolation and non-isolation in the power supply part. The isolation volume is large and the efficiency is low. In use, there are many problems in installation. It is not as good as the market prospect of non-isolated products. Here we mainly discuss non-isolation. Drive solution.

The non-isolated LED fluorescent lamp power supply is based on the A704WFT of Taiwan Guangpeng Technology Co., Ltd., and the MOS tube of the A704WFT is plugged in. The basic circuit is shown in Figure 1:

Basic circuit diagram

Power characteristics:

1. Mains power supply (85~265V), external MOS, power is not limited;

2, low power consumption, high efficiency, high power factor;

3, with load open circuit and short circuit protection, output overvoltage protection function, current ripple characteristics, output current is similar to DC DC, no lamp flash phenomenon, high load capacity, can drive up to 600mA current;

4, the customer has made 15W standard circuit, efficiency 88%, power factor 0.91, can pass CE certification, including EN55015 EMI test, lighting fixtures below 25W class C harmonic standard, EFT 1000V pulse group test, ESD 2000V static test. The 15-string application can control the output low voltage, eliminating the need for traditional large capacitors and controlling the output harmonics of the current.

5, A704's LED daylight application program is relatively mature and reliable, we can provide PCB line and EMC table reference for LED fluorescent lamp to improve the speed of customer design and development products!