Although many people have heard of electrostatic discharge (ESD), there are still
many facts about it that may surprise them. Misconceptions and myths still
surround ESD, and it is a more common phenomenon than most realize. Here are
ten interesting facts about ESD:
1. High Humidity Increases ESD Activity. While it is commonly believed that low
humidity increases the risk of ESD, high humidity environments can also be
problematic. Moisture in the air can create a conductive path for static charges,
leading to unexpected ESD events.
2. Everyday Actions Can Generate Significant Static Charges. Simple daily activities can create surprisingly high static voltages:
- Walking across a carpet: 1,500V to 35,000V
- Walking across a vinyl floor: 250V to 12,000V
- Using vinyl envelopes: 600V to 7,000V
- Sitting on a polyurethane chair: 1,500V to 18,000V
3. Electronic Components Have Varying Sensitivities to ESD. Different components react differently to ESD:
- CMOS: 250V to 3,000V
- SAW: 150V to 500V
- VMOS: 30V to 1,800V
- EPROM: 100V and above
- Schottky Diodes: 300V to 2,500V
4. ESD Damage Can Be Hard to Detect.
Components degraded by ESD might pass initial tests but fail later under stress.
This latent damage makes ESD issues challenging to diagnose and pinpoint.
5. ESD Protection is Essential, Not Optional.
Without proper management, ESD will cause damage most of the time. Effective
ESD protection devices are crucial for safeguarding sensitive electronics.
6. ESD is Not a Modern Problem.
People have been aware of ESD for hundreds of years. In the 1800s, measures
were taken to protect black powder from ESD, illustrating the longstanding
awareness of static electricity's dangers.
7. Common Myths Persist About ESD.
One prevalent myth is that touching metal objects discharges static completely,
making it safe to handle ESD-sensitive materials. Body charges can rebuild almost
immediately.
8. Insertion into Printed Wiring Boards Doesn't Ensure Safety.
Simply inserting components into printed wiring boards (PWBs) does not protect
them from ESD. They still require careful handling and appropriate ESD
precautions.
9. ESD Can Come from Unlikely Sources.
Innocuous items, like charged plastic faceplates, can cause ESD problems.
Identifying and mitigating these sources is crucial in ESD management.
10. ESD Solutions Can Be Simple and Cost-Effective.
Not all ESD management requires expensive equipment. Sometimes, avoiding
simple operational errors and using basic ESD controls can effectively mitigate
risks.
ESD remains one of the most intriguing aspects of electronics. Despite being well-
studied, new discoveries about ESD continue to emerge, challenging both experts
and amateurs to stay informed. By understanding and implementing effective ESD
protection strategies, the reliability and longevity of electronic devices can be
significantly enhanced.
