Understanding Static Electricity Prevention in LED Displays
LED displays place great emphasis on anti-static measures. The following are some points regarding static electricity and its prevention:
1. Sources of Static Electricity: The main sources of static electricity affecting circuits include the human body, plastic products, and related equipment and instruments. Static electricity sources from the operating environment include:
1) Objects and materials
2) Floors, workbenches and chairs
3) Work clothes, packaging containers
4) Painted or waxed surfaces, organic and fiberglass materials
5) Cement floors, painted or waxed floors, plastic tiles or linoleum flooring
6) Synthetic fiber work clothes, non-conductive work shoes, clean cotton work clothes
7) Plastics, packaging boxes, cartons, bags, trays, foam padding.
2. Failure Modes of Electrostatic Discharge: Sudden failure and latent failure.
Over 90% of electrostatic discharge failures in the operating environment are latent failures, manifesting as weakened circuit resistance to electrical overstress and shortened lifespan. 3. Anti-static Measures:
1) Provide electrostatic knowledge and related technical training to personnel using electrostatic-sensitive circuits.
2) Establish an anti-static work area, using anti-static flooring, anti-static workbenches, anti-static grounding leads, and anti-static equipment, and maintain the relative humidity above 40%.
3) Static electricity can cause damage to electronic equipment anywhere from the manufacturer to field equipment. Damage is caused by insufficient and ineffective training and equipment malfunction. LEDs are electrostatic-sensitive devices. Ingan chips are generally considered "first" susceptible to interference.
4) ESD-damaged equipment may exhibit dimming, blurring, extinguishing, short or low VF or VR. ESD-damaged equipment should not be confused with electronic overload, such as due to incorrect current design or drive, chip mounting, wire shielding grounding or encapsulation, or ordinary environmental induced stress.
5) ESD safety and control procedures: Most electronic and electro-optical companies have very similar ESD control and manipulation procedures for all devices. These procedures are used because ESD has been used in instruments for detecting quality issues since ancient times. ISO-9000 certification also includes it as a standard control procedure.
4. Transportation and Packaging
During routine operations, ESD-sensitive equipment should always be stored in anti-static bags or containers. This includes detailed inventory, transportation, and work-in-place (WIP) procedures. Precautions during transportation include using consumable trucks, boxes, or other equipment, such as those with conductive wheels or trolley links, to ensure that ESD-sensitive equipment is grounded during transport.