IEC 60950 ESD Test

Electrostatic discharge (ESD) is an all too frequent issue among electronic devices, often leading to damage, malfunctions and data loss. Testing ESD capabilities is critical in order to evaluate reliability and anti-interference capabilities; IEC60950 contains detailed testing specifications; this article briefly outlines its process as well as its significance when product designing.

Electrostatic Discharge Definition and Risk Considerations

Electrostatic discharge refers to the transference of charges between charged objects, commonly marked by a click or spark. It can occur either via direct physical contact (for instance between humans and devices) or indirect coupling between devices and charged objects (i.e. coupling between devices and charged objects).

Electrostatic discharge presents several risks:

1. Device damage: High-energy discharges can damage devices by burning components out. 2. Malfunction: Lower energy discharges may cause data loss or program crashes, whil repeat discharges impair device reliability and compromise its performance.

ESD Testing is therefore an integral component of design and production processes.

Overview of IEC60950 Standard

IEC60950-1, established by the International Electrotechnical Commission, addresses safety considerations when designing and manufacturing devices as well as ESD testing requirements.

Standard testing seeks to establish an anti-interference capability of devices by simulating human contact and coupling between an object charged by electricity, with human beings as its subjects. Testing methods typically cover:

1. Direct discharge testing simulates human contact while activitative and indirect discharge tests simulate coupling between charged objects and the device in various configurations (direct/indirect discharge tests respectively).

ESD Testing Methods

There are two ESD testing methods.

1. Direct Discharge Testing:

Test Equipment consists of either Human Body Model (HBM) or Machine Model (MM), while Testing Procedure involves placing a charged object against its surface to mimic human contact; whilst Voltage for Testing Ranges from 2kV-8kV for proper results.

2. Indirect Discharge Testing: For this test, Charged Device Model (CDM) equipment and procedure are utilized; during which, an indirect discharge object such as an electric charge object is brought within reach but does not contact directly the device under test, with test voltage levels between 2kV to 4kV being employed for tests of indirect discharges.

ESD Test Levels

According to IEC60950-1 standards, four ESD testing levels exist:1. Contact Discharge (V = + 2kV to V = 8 kV); (2) Air Discharges with Voltage between +-2KV and 8 kV and mes3 Indirect Discharge with Voltage between 2 kV to 4kV are all effective tests of electrostatic discharge (ESD).

When choosing test levels, various factors including device type, application environment and user requirements must be taken into consideration.

Importance of ESD Testing

1. Improve product reliability: Used to identify and optimize device electrostatic resistance.

2. Acknowlencing international standards: Passing IEC60950-1 test ensures compliance with global market requirements.

3. Minimizing After-sales Risks: Minimize ESD-related failures while simultaneously decreasing costs related to after sales service and support.

Before conducting any tests, certain precautions must be observed: 1. Testing Environment: Keep temperatures and humidity consistent to maintain accuracy for testing environments.

2. Device Calibration: Regularly calibrate equipment to ensure voltage accuracy.

3. Electrostatic Protection: Test personnel should wear anti-static gear when performing tests to avoid interference with results.

ESD testing is an integral component of device evaluation, serving to establish their anti-interference capabilities under IEC60950-1 standard requirements and guarantee stable device operation within complex environments while increasing market competitiveness.