ESD protection

AN1702

10/11

8

ESD protection

Common situations such as handling, connection and maintenance can create electro-static

discharges (ESD), which can damage related devices. The use of transceivers with high

ESD immunity in e-meter applications is recommended. In order to evaluate ESD immunity,

two standards are largely used at this time: the JEDEC standard (Human Body Model),

which simulates the ESD of a human body contacting the device, and the ISO standard (IEC

61000-4-2), which simulates the ESD of a human body handling a tool (screwdriver, or a

metallic connector, etc.), approaching (Air Discharge) or contacting (Contact Discharge) the

device. The IEC 61036 standard requires that the device be immune to contact discharges

(ISO IEC 61000-4-2) of 8 kV, while the DL/T 645 standard requires meter equipments to

tolerate 15 kV (HBM) discharges. The ST485EB is compliant to both these specifications.

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Revision history

Table 1.

Revision history

Date

Revision

Changes

11-Sep-2006

1

First release

28-Sep-2007

2

– No content changes, document reformatted.

– ST485ER replaced by ST485EB