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1. Driving power supply

According to the characteristics of power supply, it can be divided into constant current power supply and non constant current power supply. Their differences are:

Constant current source: no matter how large the load voltage is, the load current is stable. At present, there are many LED drivers, which is also reflected in the stroboscopic of the lamp tube. Therefore, it is suggested that the constant current power supply ensures the stability of the current input to the lamp tube. Even if the luminous brightness of the lamp bead is stable at a value, there is no slender bright and dark, Then let the LED achieve the purpose of no frequency eye protection.

Classified by barrier power supply and non barrier power supply

Difference: the blocking power supply uses the transformer to reduce the 220V voltage to a lower voltage through the transformer, and then rectifies it into DC output for computer use. Since the main coil of the transformer bears 220V voltage and the secondary coil only bears the output low AC voltage, and the primary and secondary coils are not directly connected, it is called blocking power supply. The non blocking power supply is directly input to the electronic circuit with 220V. After voltage reduction and output through electronic components, the input and output are directly connected through electronic components, so it is called non blocking power supply;

On the surface, the difference between the two is whether there is a transformer or not. However, please note that some manufacturers choose to tap directly on the main coil to extract low voltage in order to save cost. This method seems to have a transformer. In practice, there is no secondary coil, which can not be regarded as blocking the power supply!

The advantages of barrier power supply are: it will not pose a threat to human body. Wide voltage is well reflected. Non barrier power supply is also very mature now. The voltage scale is slightly worse than that of barrier power supply. The voltage scale is between 110v-300v, while barrier power supply can achieve 60-300v. The bump current is very uniform

The barrier type drive is safe, but the power is low, and the non barrier type drive power is high. The barrier type or non barrier type drive should be selected according to the requirements of practical application.

As far as the circuit structure is concerned, most of the current barrier schemes are AC / DC flyback circuit schemes, so they are more messy and cost more than circuits. The non blocking type basically selects the DC / DC boost or buck circuit, which is simpler than the circuit, so the cost is relatively low.

Constant current accuracy: the barrier type can achieve within ± 5%, while the non barrier type is difficult to achieve.

In the application field: now in the LED lamps with the mains power as the input power supply (especially the lamps integrated with the light source), based on the principle of safety, the non barrier plan is basically no longer selected. However, there are exceptions. Due to the constraints of structure and space, LED fluorescent tubes still use non barrier plans. In the low-voltage power supply LED lamps, the principle of giving priority to power and cost is the selection of non barrier plan.

2. LED aluminum substrate

LED fluorescent tubes use more LED aluminum substrates, or in order to save costs, some businesses will use fiberglass panels.

Difference: the heat dissipation of aluminum substrate is better than that of aluminum substrate. The price of aluminum substrate is more expensive than glass fiber board, but heat dissipation is directly concerned with the service life and light decay of LED. Therefore, for LED fluorescent tubes, glass fiber board is better than aluminum substrate. The answer must be aluminum substrate.

3. PC cover and aluminum groove

Meanwhile, the PC cover can be a high transmittance light cover, which is also called transparent cover and diffusion cover.

Difference: the light transmittance of the transparent cover is 90-95%, and the lamp beads can be seen. Although it has a good light transmission effect, the light is more eye-catching. The light transmittance of the diffusion cover is 80-90%. The light announced by the lamp tube of the diffusion cover is relatively soft, unobtrusive and easier to bear. Therefore, the diffusion cover is mostly used as the PC cover in the market.

4. Plug

5. Heat conducting paste

6. Light source - led bulb

LED fluorescent tubes use LED beads from 3528 to 3014 at the beginning, and then from 3014 to 2835 at present. The technology has been improving. During this period, the data cost of the beads is also declining, but there is no doubt that most of the cost of LED fluorescent tubes comes from LED beads, followed by the driving power supply. Now LED fluorescent tubes are also packaged with cob light source, but compared with LED beads, the beads have better heat dissipation and luminous angle.

Article from: LED fluorescent tube manufacturer http://mushuren.cn/