Electrostatic Discharge (ESD)

Applicable Test Standard

International Electrotechnical Committee (IEC)

IEC/EN 61000-4-2: Electromagnetic Compatibility (EMC) – Testing and Measurement Techniques – Electrostatic Discharge Immunity Test

Electrostatic Discharge is a high voltage event from the release of electrical energy caused by static electricity or electrostatic induction. ESD can cause permanent damage to electronics and integrated circuits.

There are three models for assessing the survivability/susceptibility of electronic devices to ESD:

1. HBM - Human Body Model
2. MM - Machine Model
3. CDM - Charged Device Model

IEC 61000-4-2 is the series of specifications used to test the susceptibility of electronic devices to ESD. It embodies the guidelines and requirements for the test cell geometries, generators, test levels, discharge rate and waveform, types and points of discharge, and functional criteria for gauging product survivability. The purpose is to establish a benchmark for testing - Testing methods and standards are set for Direct Discharge and Air Discharge.

Contact Discharge – Discharge via contact with a conductor. Preferred test method; more stringent.

Air Discharge – Discharge without direct contact and used only in special circumstances. For example, when the metal (conductive) part of a remote control is covered in insulation.

Electrostatic Discharge Test Levels



Contact Discharge
Air Discharge


Level
Voltage/kV
Level
Voltage/kV


1
2
1
2


2
4
2
4


3
6
3
8


4
8
4
15


X
Special
X
Special



ESD and Surge Differences




ESD
Surge


Specifications
IEC 61000-4-2
IEC 61000-4-5


Features
High – Voltage, Low Current
High –Current, Low – Voltage


Energy
(Micro-joule)
Large (Joule)


Time
0.7~1.0nS
8x20 or 10x1000µS