Electronic cigarette popular screen: digital tube working principle, structure composition and production process

Electronic Cigarette popular screen: digital tube working principle, structure composition and production process
I. Introduction and working principle
LED digital tube (LED Segment Displays, LED Module) is a very common digital information display device, in a variety of digital products, home appliances, industrial digital instrumentation and other fields with a wide range of applications.

LED digital tube is actually composed of seven light-emitting tubes in the shape of a figure of eight, plus the decimal point is eight. These segments are represented by the letters a,b,c,d,e,f,g,dp. When the specific segment of the digital tube plus the voltage, these specific segments will light up, and finally display the content.
Structure
Digital tube is simply composed of PIN pin (pin), plastic shell (PC, PPO), PCB, light-emitting diode (LED beads), display panel, solid crystal adhesive, high temperature tape, encapsulation glue and so on. After the purchase of raw materials by the quality of inspection, all kinds of material performance and appearance testing, qualified into the warehouse on the production line, open the digital tube production journey.

Third, the production process
The common manufacturing process of digital tube is: wear PIN (insert PIN), solid crystal (die bonding), welding wire (wire bonding), pre-test/semi-finished testing (semi-finished testing), glue filling (glue filling), labelling and film pasting, finished products testing, packaging and packaging. (finished products testing), packaging (wrap).

The first main process is the combination of PCB and needle guide. Usually by automatic jumping needle guide equipment will guide the needle through the PCB holes, and then through the pressure will guide the needle and PCB riveted good.
The second process is binding. There are light-emitting chip binding and aluminium wire binding. Light-emitting chip is completed by the automatic chip binding equipment, the first point on the PCB board on the crystal glue and then put on the chip, through the high temperature curing crystal glue to make the chip fixed. Then the aluminium wire binding, one end of the aluminium wire is welded with Pcb, and one end is welded with the light-emitting chip.
The third process for the test process, the binding of good products for electrical testing, you can test the short circuit, open circuit, leakage, wrong solid and other issues. However, this process many manufacturers will be the second process of quality control after the cancellation of the test process.
The fourth process for the filling process. The sealant is generally epoxy resin through the filling of foam, the third test good products into the plastic shell of the filling, and then after a long period of high-temperature curing moulding.
The fifth process for the finished product testing process. The cured digital tube and then test the performance. The test performance is similar to the third process, but the relevant parameters can be appropriately relaxed (according to different customer needs). Some special digital tubes need to paste the mask, guide pin shaping and other processes.
The sixth is the packaging process. This process is mainly for the appearance of the product testing, printing code logo printing and packaging work. Each company's individual processes will have to increase or decrease, switch, etc., are based on internal process demand adjustment.
Fourth, the selection of
- Font height or size, such as 0.4 inch, 0.56 inch, 0.8 inch, etc.
- The number of digits of the digital tube, to determine a display component, the maximum content that can be displayed.
- The light-emitting colour of the digital tube (light-emitting wavelength), such as: single red, yellow, blue, green, white, RGB seven-colour and so on;
- The brightness of the digital tube, normal brightness or high brightness, etc..
- The working voltage and current of the digital tube.
- The colour of the silkscreen (panel) on the surface, usually cream, black or grey, etc.
- Internal connection: common negative or common positive.
- Operating life.
- Operating temperature and humidity.
- Other properties, such as: waterproof level, dustproof, UV protection, crack resistance, flame resistance, super impact aging and so on.
- The appearance of LED digital tube requires uniform colour, no partial discolouration and no air bubbles, etc.

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