USB interface is widely used in audio-visual and data processing equipment. The following is a brief introduction to a circuit protection solution for USB port. 

Background

The protection circuit protection used in this solution is TVS Diodes. The transmission rate of USB2.0 is 480Mbps, and the communication rate is relatively high. In addition to the operating voltage, TVS diodes needs to consider the junction capacitance when it is used in communication. Therefore, TVS diodes with too high junction capacitance cannot be used. Because too high junction capacitance will seriously affect communication in mega-level communication, resulting in data loss. So we need to use a dedicated USB protection device. TVS diodes with anti-ESD capability.

SOCAY Solution and Components

Transient suppression diode(TVS Diode )

【ESD05V14T-LC】Vrwm：5.0V；Vb：6.0V；Vesd：8KV/15KV；Ct（f=1MHz）：1.2pF；Package: SOT-143

Applications

1. Laptop, PAD, home desktop computer, industrial computer

2. Network printer

3. Set-top box

4. Mobile handheld devices

5. TV

6. Vehicle

7. Other devices with USB2.0 ports

8. DVD recorder

The Solutions Notes

1. Use 1 TVS on the USB2.0 power line to protect the ground and clamp the electrostatic voltage

2. The junction capacitance of the TVS is less than 1.2pF, and the transmission signal can be completed at the highest speed of USB2.0 of 480Mbps

3. The TVS package is SOT-143, which is small in size, saves PCB space, and is convenient for engineers to design