Nexperia

PUSB3AB2DF

Extremely low clamping low capacitance ESD protection

reverse

dI

dV

Vhold

Ihold

It1

Vt1

V

I

forward

aaa-027670

VRWM

Rdyn = dV/dI

Fig. 9. V-I characteristics for a bidirectional ESD protection diode

10. Application information

The device is designed for the protection of two signal lines from surge pulses and ESD damage.

The device is suitable on lines where the signal polarities are both, positive and negative with

respect to ground.

The device uses an advanced clamping structure showing a negative dynamic resistance. This

snap-back behavior strongly reduces the clamping voltage system behind the ESD protection

during an ESD event. Do not connect unlimited DC current sources to the data lines to avoid

keeping the ESD protection device snap-back state after exceeding breakdown voltage (due to an

ESD pulse for instance).

aaa-030287

ESD protection diode

GND

lines to be protected

Fig. 10. Application diagram

Circuit board layout and protection device placement

Circuit board layout is critical for the suppression of ESD, Electrical Fast Transient (EFT) and surge

transients. The following guidelines are recommended:

1. Place the device as close to the input terminal or connector as possible.

2. Minimize the path length between the device and the protected line.

3. Keep parallel signal paths to a minimum.

4. Avoid running protected conductors in parallel with unprotected conductors.

5. Minimize all Printed-Circuit Board (PCB) conductive loops including power and ground loops.

6. Minimize the length of the transient return path to ground.

7. Avoid using shared transient return paths to a common ground point.

8. Use ground planes whenever possible. For multilayer PCBs, use ground vias.

PUSB3AB2DF

All information provided in this document is subject to legal disclaimers.

© Nexperia B.V. 2019. All rights reserved

Product data sheet

22 November 2019

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