PRTR5V0U2AX_2

© NXP B.V. 2006. All rights reserved.

Product data sheet

Rev. 02 — 21 December 2006

5 of 10

NXP Semiconductors

PRTR5V0U2AX

Ultra low capacitance double rail-to-rail ESD protection diode

7.

Application information

Handling data rates up to 480 Mbit/s, USB 2.0 interfaces require ESD protection devices

with an extremely low line capacitance in order to avoid signal distortion.

With a capacitance of only 1.8 pF, the NXP PRTR5V0U2AX offers IEC 61000-4-2, level 4

compliant ESD protection.

The PRTR5V0U2AX integrates two ultra-low capacitance rail-to-rail ESD protection

diodes and an additional ESD protection diode in a small 4 lead SOT143B package.

charging of the supply.

To achieve the maximum ESD protection level, no additional external capacitors are

required.

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 PRTR5V0U2AX as close to the input terminal or connector as possible.

2. The path length between the PRTR5V0U2AX and the protected line should be

minimized.

3. Keep parallel signal paths to a minimum.

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

5. Minimize all printed-circuit board 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. Ground planes should be used whenever possible. For multilayer printed-circuit

boards, use ground vias.

Fig 3.

Application diagram: USB 2.0

006aaa485

D

+

D

−

D

+

D

−

GND

USB controller

common mode

choke

protected IC/device