The liquid crystal module is a component that assembles the liquid crystal device and the LCD controller
The liquid crystal module is a component that assembles the liquid crystal device and the LCD controller, the drive circuit, and the circuit board PCB. He can directly connect to the computer. When using this type of module, in addition to the precautions for general LCD screen use, the following items should also be paid attention to when assembling and using:
1. Handle the protective film
There is a protective film on the surface of the assembled liquid crystal module to prevent it from staining the surface during assembly. It cannot be removed before the entire machine is assembled to avoid staining or staining the display surface.
2. Add padding
It is better to install a gasket of about 0.1mm between the module and the front panel. The panel should also remain flat. Make sure that no twisting force is generated after assembly. And improve the seismic performance.
3. Strictly prevent static electricity
The control and drive circuit in the LCD module is a low-power, low-voltage CMOS circuit, which is easily broken down by static electricity, and the human body sometimes generates high-voltage static electricity up to several volts or hundreds of volts, so We must be very careful in operation, assembly and use, and we must strictly prevent static electricity. to this end:
1) Do not touch the outer leads, the circuit on the circuit board, and the metal frame by hand.
2) If direct contact is necessary, the human body and the module should be kept at the same potential, or the human body should be well connected to the ground.
3) The soldering iron used during soldering must be well grounded to ensure that there is no leakage.
4) Some operating electric cones and other tools must be well grounded to ensure that there is no leakage.
5) Do not use a vacuum cleaner for cleaning. Because the vacuum cleaner may generate strong static electricity.
6) When the air is relatively dry, static electricity may also be generated. Therefore, the humidity in the working room should be above RH60%.
7) Resistance contact should be formed between the ground, chairs, carts, workbenches, shelves, and tools to maintain the same potential, otherwise static electricity may also be generated.
8) When taking out or putting it back in the packaging bag or moving the position, you should also be extra careful not to generate static electricity. Do not change or discard the original packaging at will.
9) Static breakdown is a type of damage that cannot be repaired, so be careful not to be careless.
4. Some precautions during assembly operations.
The module is carefully designed and assembled by people, please do not process or trim it by yourself.
1) The metal frame claws must not be twisted or disassembled at will.
2) Do not modify the shape, circuit, assembly holes, and components of the processed PCB board at will.
3) The conductive tape cannot be modified.
4) Please do not modify any internal brackets.
5) Do not touch, drop, bend, or twist the module.
When welding the external and interface circuits of the module, the following procedures should be followed.
1) The temperature of the soldering iron tip should be less than 280℃
2) The welding time must be less than 3-4 hours
3) Welding material: eutectic, low melting point.
4) Do not use acidic flux.
5) Try not to repeat the welding more than three times, and each repetition needs to be performed at an interval of 5 minutes
6. Module usage and maintenance
1) When the module is used to connect and disconnect the power supply, it must be done by the sequence of the figure. That is: it must be input from the positive power supply (5±0.25V) before the signal voltage can be input. If the signal voltage is input before the power is stably connected or after it is disconnected, the integrated circuit in the module will be damaged and the module will be damaged.
Power 4.75V 4.75V
A power-on sequence b, power-off sequence
2) Dot matrix module is a high-channel number of liquid crystal displays, which has a great relationship with display contrast, viewing angle, temperature, and driving voltage. Therefore, Vee should be adjusted to the best contrast and viewing angle. If Vee is adjusted too high, it will not only affect the display but also affect the life span of the display device.
3) When used at the lower limit of the specified operating temperature range, the display response will be very slow. When used at the upper limit of the specified operating temperature range, the entire display interface will directly turn black. This is not damage. After the temperature range is restored, it can be restored to normal.
4) Pressing hard on the displayed part will produce an abnormal display, as long as we cut off the power supply and reconnect it to restore it.
5) When the surface of the LCD screen or the module is fogged, do not go to work, because this will cause a chemical reaction of the electrode and break the wire.
6) After long-term use in sunlight and strong light, the shaded part may produce residual images.
7. Storage of LCD module
For long-term storage (such as several years or more), we can recommend the following methods.
1) Put it into a polyethylene bag (preferably with anti-static coating), and seal the mouth.
2) Store between -10℃—+35℃.
3) Keep it in a dark place and avoid glare.
4) Never put anything on the surface.
5) Strictly avoid storage under extreme temperature/humidity conditions. If it must be stored under special conditions, it can also be stored at 40℃, 85%RH, or 60℃, less than 60%RH, but it should not exceed 168 hours.