Electrostatic discharge

Electric sparks require a field strength above approximately 4 × 106 V/m in air, as notably occurs in lightning strikes.

ESD can cause harmful effects of importance in industry, including explosions in gas, fuel vapor and coal dust, as well as failure of solid state electronics components such as integrated circuits.

Electronics manufacturers therefore establish electrostatic protective areas free of static, using measures to prevent charging, such as avoiding highly charging materials and measures to remove static such as grounding human workers, providing antistatic devices, and controlling humidity.

In all these cases, the breaking of contact between two materials results in tribocharging, thus creating a difference of electrical potential that can lead to an ESD event.

[2] Electrostatic discharge (ESD) phenomena vary in complexity and magnitude, with the electric spark being the most visible and dramatic example.

People may experience this as a small jolt of discomfort, but ESD can inflict severe damage on electronic components, potentially leading to malfunctions and failures.

In hazardous environments where flammable gases or dust particles are present, ESD can trigger fires or explosions.

It is possible for a person to carry a charge that, while undetectable to the human senses, can still be potent enough to harm delicate electronics.

Some components can be compromised by discharges as faint as 30 V, with such damage sometimes not becoming apparent until significant usage has occurred, thus affecting the lifespan and performance of the devices.

The diatomic oxygen molecules are split, and then recombine to form ozone (O3), which is unstable, or reacts with metals and organic matter.

Due to dielectric nature of electronics component and assemblies, electrostatic charging cannot be completely prevented during handling of devices.

In addition, it is important to prevent ESD when an electrostatic discharge sensitive component is connected with other conductive parts of the product itself.

Any built-up static charges dissipate without the sudden discharge that can harm the internal structure of silicon circuits.

[5] A common example is that semiconductor devices and computer components are usually shipped in an antistatic bag made of a partially conductive plastic, which acts as a Faraday cage to protect the contents against ESD.

The capacitor is charged to a specified high voltage from an external source, and then suddenly discharged through the resistor into an electrical terminal of the device under test.

[6] Another specification referenced by equipment maker Schaffner calls for C = 150 pF and R = 330 Ω which provides high fidelity results.

Other standardized ESD test circuits include the machine model (MM) and transmission line pulse (TLP).