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EMC DESIGN GUIDE FOR ST MICROCONTROLLERS

Figure 21. Grounding the Human Body

(1) Wrist ring

(2) Grounding wire: threaded copper wire, vinyl covered, about 1 meter

(3) 250 KW to 1 MW resistance is built in

Device handling:

Static control wrist straps, used and connected properly, must be worn.

All tools, persons, testing machines, which could come in contact with device leads, must be

conductive and grounded. Each tabletop must be protected with a conductive mat, properly

grounded. Use static control shoe strap. Use vacuum pipes.

Storage box:

Keep parts in the original packing bags up to the very last moment of the production line.

If bigger containers are used for in-plant transport of devices or PC boards, they must be elec-

trically conductive like the carbon-loaded types. Avoid use of high dielectric materials (like pol-

ystyrene) for sub-assembly construction, storing, and transportation.