Static power control
1. In case of contact with sensitive devices
1. Static electricity is not allowed-JEDEC625
2. The static voltage is less than 100V/200V-the industry point of view
2. Control of insulating materials
1. Insulating material is the most important factor in generating static electricity
2. Not all insulating materials will form static electricity, so there must be control measures to avoid risks:
a. Register the insulating materials in the EPA and establish a list. The list should indicate whether each insulating material is safe, and if it is not, what is the treatment method;
b. Perform static voltage testing on insulating materials to see if they meet the requirements of the EPA. If the requirements are exceeded, appropriate measures should be taken and necessary inspections should be carried out.
3. Treatment of insulating materials that constitute static power
a. Cleaning up: the products that are not related to production are removed from the EPA
b. Isolation: stay away from sensitive devices more than 30 cm. Special areas can be designated when necessary;
c. Shield: put it in an anti-static package, such as putting paper documents in an anti-static file bag;
d. Material replacement: Replace with anti-static material;
e. Anti-static treatment: use anti-static agent to wipe and soak to make it an anti-static material;
f. Ionization: Use ionization equipment to neutralize static electricity.
Four, static electricity source and ambient temperature and humidity
1. The higher the humidity of the same material, the lower the friction voltage;
2. When the humidity is high, the surface resistance of most insulating materials will decrease, and static electricity will easily discharge;
3. The following three materials are usually ESD safe when the humidity is above 50%: A, cotton fabrics; B wooden materials; C, paper made of natural fibers;
4. Although the higher the humidity, the more conducive to the control of static electricity, but we must also consider the acceptable degree of the process.
5. Static electricity source and ambient temperature and humidity
1. In winter with low temperature, the indoor humidity may be lower than the outdoor due to the heating of the air, so special attention should be paid to the problem of static electricity;
2. Temperature and humidity are important influencing factors for process and measurement, so the measurement and control are carried out.