Unfortunately, as well as transmitting high-speed data and significantly greater power, the additional copper data lines of USB 3.0 can also transmit harmful voltage transients. A co-ordinated circuit protection approach can help protect against damage from overcurrent, overvoltage and ESD events.

Overcurrent protection devices help designers meet the new high-current requirements of USB 3.0. For example Bourns offers a broad range of different package sizes for overcurrent  protection up to 0.9A for USB 3.0 host controllers and up to 1.5A for USB ports with charging capability. Increasing the number of ports makes greater demands of the overcurrent protection device, so the energy absorbing-capacity requirement is higher when one or more ports are ganged on the device. PolySwitch-devices from Tyco Electronics provide protection for up to two ganged ports: they provide a simple, space-saving solution.

Overvoltage protection devices offer designers the simplicity of a traditional clamping diode while obviating the need for significant heat sinking in the event of sustained overvoltage.

ESD protection devices like the PESD range from Tyco Electronics provide the low capacitance (typically 0.2pF) required for high-speed data transmission. They are available in  the most popular for factors: 0603, 0402 and 0201.

Useful links:

Bourns

USB 3.0 - ESD & Overcurrent Protection 

Tyco Electronics

Tyco Electronics circuit protection pages

USB 2.0 and USB 3.0 circuit protection considerations for hard disc drives

Low power consumption PolyZen Device addresses USB 3.0 leakage current requirement in suspend mode

Circuit protection considerations for USB 3.0

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