FRIDA TFT LCD DISPLAY MAINTENANCE PLAN
I. Strictly prevent static electricity
The control and driver circuit in the module is a low-voltage and micro-power CMOS circuit, which can be easily damaged by static electricity. Static breakdown is an irreparable damage, so must be careful. Therefore, you should be extremely careful to prevent static electricity during operation, assembly and use. You should follow as below:
1. The soldering iron must be well grounded, no leakage of electricity.
2. If it must be touched directly, the body should be well grounded with the module, or the hand should be touched with the metal frame of the operating table to discharge.
3. Do not touch the external lead with your hands, circuit and IC on circuit board, etc.
II. Treatment of protective film
There is a protective film on the surface of the finished module to prevent from being stained during assembly, it should not be removed before the end of assembly of the whole machine, so as not to stain or damage the display surface.
III. Add gasket
It’s better to add gasket of about 0.1mm between the module and the front housing, which should be kept flat to avoid distortion after assembly.
IV. Welding of external leads and interface circuits of modules shall be carried out in accordance with the following provisions
1. Do not let the soldering tin drop onto the circuit board of the LCD displays during welding. Otherwise, the displays will be abnormal due to the short circuit.
2. Temperature of soldering iron: 280±10°C. Welding time: 3~4S. Welding material: eutectic type, low melting point. Repeat welding shall not exceed 3 times.
3. If the connection between the LCD module and other peripheral circuits needs to be welded or the original connection head needs to be changed, please confirm that the LCD module has passed the quality inspection in advance.
4. Do not physically damage the LCD displays and PCB. Otherwise it can not be repaired.
V. Matters needing attention during assembly operation
1. The mounting hole shall be grounded to prevent electromagnetic interference and external noise.
2. The metal frame hooks shall not be arbitrarily twisted or removed. Do not modify or process PCB outline, assembly holes, circuits and components at will. Do not modify the conductive tape at will. Do not modify any internal brackets. Do not touch, fall, bend, twist modules, backlight parts, etc.
3. The LCD module is carefully designed and assembled, please do not arbitrarily process and trim.
VI. Storage of modules
For long-term storage (e.g., several years), we recommend the following:
Put into the polyethylene bag (preferably with anti-static coating) and seal the mouth. Place in dark place and avoid bright light. Never put anything on the surface. Strictly avoid to storage beyond the limited temperature and humidity conditions (the polarizer of LCD modules can not bear high temperature and humidity).
VII. Use and maintenance of modules
1. The external lead of LCD module can not be wrongly connected, otherwise it may cause over current, over voltage and other destructive phenomena to the LCD module components.
2. When the LCD module is used below the specified operating temperature range, the response will be slow. When the module is used above the specified operating temperature range, there is risk that it will be damaged. It should not be used or stored beyond the limited storage temperature. If the temperature is lower than the crystallization temperature, the liquid crystal will crystallize, the alignment layer will be destroyed and the device will be scrapped. If the temperature is too high, the liquid crystal will become isotropic liquid, it will lose the function of liquid crystal device.
3. When the LCD module is connected to and disconnected from the power supply, the signal level can only be input after the positive power supply (5±0.25V) is stably connected. If the signal level is input before or after the power is stabilized, IC and other circuits in the module may be damaged.
4. The contrast ratio and viewing angle are closely related to the temperature and driving voltage for dot matrix LCD module. Therefore, if VEE is too high, it will not only affect the performance, but also shorten the lifetime of the module.
5. When there are water droplets on the surface of LCD module, it should be quickly wiped off. Contacting with water droplets for a long time will make the LCD module discoloration or appear spots.
6. Do not knock the IC at the backside of PCB board to prevent short circuit of adjacent Pin.
7. Pressing the display area hardly will make abnormal performance. Please cut off the power, wait for a moment, re-power, then it will return to normal.
8. Quickly wipe the LCD module with absorbent cotton or other soft cloth when there is a stain.