How to improve the quality of LED display products
I. Technology and information selection
1. The use of advanced technology, technology
LED industry process is numerous, and has been constantly progressing and updating, LED display manufacturers to choose advanced, suitable for manufacturers of the current situation of the technology, and to be forward-looking.
2. Select high-quality materials
Raw material is one of the decisive factors in determining the final quality of the product, so LED display manufacturers should try to choose quality assurance manufacturers to buy high-quality materials.
Second, production scale, standardization
1 anti-static
Static electricity is a great danger to the electronics industry, so LED display manufacturers must do a good job of static electricity protection in the production of products.
2 over wave soldering temperature and time
LED display manufacturers strictly control the wave front welding temperature and time over the furnace, it is recommended that: preheating temperature of 100 ℃ ± 5 ℃, the highest not more than 120 ℃, and preheating temperature rise requires a smooth, welding temperature of 245 ℃ ± 5 ℃, welding time is recommended to be no more than 3 seconds.
Do not vibrate or shock LED after the furnace until the return to room temperature. Wave soldering machine temperature parameters should be tested regularly. Overheating or fluctuating temperatures will directly damage the LED or cause LED quality risks, especially for small sizes such as 3mm round and oval LEDs!
3 design current value
LED nominal current of 20mA generally recommended for LED display manufacturers its maximum use of current is not more than 80% of the nominal value, especially for point spacing is very small display, due to poor heat dissipation conditions, should also reduce the current value. According to experience, due to the inconsistency of red, green and blue LED attenuation rate, targeted reduction of blue and green LED current value, in order to adhere to the consistency of the white balance of the display after prolonged use.
4 mixed lights
The same color different brightness grade LED need to mix the light, or in accordance with the discrete law design of the light insertion diagram for the insertion of the light, in order to ensure the consistency of the whole screen brightness of each color. LED display manufacturers this process if there is a problem, there will be a display of local brightness inconsistency phenomenon, which directly affects the display effect of the LED display.
5 control the verticality of the light
For direct insertion LED, over the furnace to have enough process technology to ensure that the LED is perpendicular to the PCB board. Any deviation will affect the consistency of the brightness of the LEDs that have been set up, and the appearance of inconsistent brightness of the color block.
6 Heat dissipation design
LED work will heat, high temperature will affect the LED decay rate and stability, so the PCB board cooling design, box ventilation cooling design will affect the LED said.
7 soldering control
LED display in the presentation of the LED is not bright, there is often more than 50% probability for various types of soldering caused by such as LED pin soldering, IC pin soldering, row of pins row of mother soldering. These problems need LED display manufacturers to strictly improve the process and strengthen the quality inspection to solve. Vibration test before leaving the factory is also a good test method.
8 drive circuit design
Display module on the driver circuit board driver IC layout will also affect the LED brightness. As the driver IC output current in the PCB board transmission distance is too far, will make the transmission path voltage drop is too large, affecting the normal operating voltage of the LED resulting in a reduction in the brightness of the LED display manufacturers often find display module around the LED brightness than the middle of the lower, this is the reason.
