In order to produce LED displays in good quality, we should have the following technology skills.

1. Anti-static
Assembly firm of Anti-static LED electronic display screen should have control measures of electric static discharge. special antic static, conductive floor, Antistatic soldering iron, ESD TABLE MAT, wrist strap, anti-static cloth、humidity control and equipment ground(especially foot cutter needed)are some basic requirements, meanwhile it need electrostatic tested regularly.

2. Design of driver circuitry
The configuration of driver IC on the LED display module drive circuit design will affect the light of the LED. If the output current make the transmission distance is so far, it will make the pressure of the transmission path become big and led to the light will turn dark because the normal working voltage has been affected. We sometimes notice that the light in surrounding area of the led display module is darker than the center area, this is the reason why. So in order to make the display light in   no difference, we should design the distribution of its diving circuit.

3. Design the nominal current value
The nominal current of the led  current value is set to be 20mA,in regularly ,we suggest the use the electric current should no more than the 80% of the nominal current, especially for the display which has small pixel distance, since the heat dissipation of it is not so good ,we should also lowed the current. According to our experience ,since the decay rate of red, green ,blue led are not same, we should pertinently lowed the current of blue and green led ,in case the display will reach white balance for a long time.

4. Mixed lamps.
The same color of different brightness file of the  led light need to be mixed or to  plug light according to the  picture designed by the law of discrete to insure that every light of the display have the corresponding color brightness. If any problem occurred in the process, the display will have a phenomenon that some parts of the display will not have the corresponding brightness with the whole and it will directly impact the effect of display of the led display.

5. Control the perpendicularity of the LED
For DIP LED, insure that have enough technical skills that led must vertical to PCB board when soldering, if there is any deviation, the brightness correspondence will be affected and color lump of different brightness will appear.

6. Wave Soldering temperature and time
Control the wave soldering temperature and time strictly. Recommended preheating temperature 100℃±5℃,the maximum of it should not higher than120℃,and the  preheating temperature should rise steadily ,soldering temperature is 245℃±5℃,we recommend that the soldering time should not longer than 3 seconds and after soldering ,do not vibrate or shock the LED until the  temperature turn to normal state.

The configuration of temperature in wave soldering machine must need  regular check ,this is decided by the  feature of LED,overheated  temperature or temperature fluctuation will directly break the led or led to hidden quality problems especially for the size smaller than 3mm round or oval shape.

7. Virtual welding control
It was caused by all kinds of Pseudo Soldering, like the Pseudo soldering of LED pin soldering, the pseudo soldering of IC pin and Pseudo soldering of row needle row mother. All this problems required high technical skills and strength the quality inspection .the vibration test is a good way to exam the quality before left the factory.

8. Heat dissipation
When the LED is in used it will relieve heat and overheat will affect the decay rate and the stability of the LED.o the heat dissipation of the PCB board and the ventilation and heat dissipation of cabient will all affect the quality of LED.

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