AN1826 datasheet(5/5 Pages) STMICROELECTRONICS

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AN1826 - APPLICATION NOTE

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CONCLUSION

Transil™ devices assume better efficiency in terms of ESD protection and can be uni and bi-directional

suppression functions. The MOV

7 are uniquely bi-directional devices and then are not optimized to protect

sensitive ICs inputs, because these are 90% of the time dedicated to uni-directional normal operating

signals. So IC inputs to be protected will be submitted to high voltages in the negative way during surge

clamping.

Remaining voltage (VCL) for both EOS and ESD across the line is lower in the case of Transil™ than for

Varistor.

Low leakage current for Transil™ device is an important parameter to take into account when portable

equipment (as mobile phone or mobile computer) are concerned. This point will improve autonomy of

these kinds of equipment. In term of reliability Transil™ device has no ageing phenomena regarding ESD

events while Varistors are subjected to it.

In many applications safer failure are requested, this characteristic consists on a failure in short circuit

when an over sized surge occurs across the protection device. This is the failure mode of Transil™ which

assumes total security of the protected equipment.

1 ESD: ElectroStatic Discharge

2 EOS: Electrical Over Stress

3 TVS: Transient Voltage Suppressor

4 VRM: Stand off voltage

5 VCL: Clamping voltage

6 VBR: Breakdown voltage

7 MOV: Metal Oxyde Varistor

AN1826 Datasheet(PDF) 5 Page - STMicroelectronics