USB Type-C, which came out along with the USB3.1 standard, is an interface model under USB3.1. As the latest USB specification, USB3.1, a specification initiated by Intel and other large companies, increases the data transmission speed to 10Gbps. The new technology also uses a more efficient data encoding system and provides effective data throughput. It is compatible with the existing USB connectors and cables. It is also compatible with the existing USB3.0 software stack and device protocol, 5Gbps hubs and devices, and USB 2.0 products. Take the USB Type-C interface protection as the starting point to look at the USB interface electrostatic protection scheme design and the key points of electrostatic protection device selection.

　　All the key features of the USB Type-C interface are integrated into an ultra-small WLCSP package of only 1.2 mm x 1.2 mm. Due to its small size and extremely low standby power consumption, this solution is very suitable for the next wave of mobile products, dongles, travel adapters, PCs, accessories and wearable devices with new USB interface characteristics.

　　Type-C need to pay attention to the points:

　　1. The transmission speed of up to 10Gbps will inevitably lead to serious excessive EMI radiation of the port;

　　2, Type-C has a wide voltage range, high power, and fast speed, which have higher requirements for port protection devices;

　　The USB interface supports plug-and-play and hot-swappable functions of the device, so its electrostatic protection level must be high, and it has fast response speed, low capacitance, small size, and diversified packaging, which saves board space (which can meet Different product applications), low leakage current, extended battery life, low voltage and other advantages of electrostatic protection devices ESD electrostatic diodes have naturally become the first choice for electrostatic protection of USB interfaces.

　　From the perspective of product application, almost all USB interfaces will be applied to electrostatic components. The most basic thing for FAE engineers is to master the protection requirements of electronic products, the working principle of circuit protection devices, and the key points of selection. The selection of circuit protection devices is actually not troublesome. You can know whether to choose discharge tubes, TVS diodes, varistors, PTC resettable fuses, and ESD electrostatic diodes by understanding the protection requirements and protection levels of the product, and then follow each circuit protection The selection principle of the device and factors such as working voltage and current can determine the final model.

　　The product selection of electrostatic protection components is ultimately to select the appropriate ESD model according to the specific needs of each customer. When selecting models and providing product solutions for customers, we must remember to follow the following two principles:

　　1. Vdrw ≥ working voltage on the circuit

　　2. Choose SMD varistor or diode according to the application port and the protection level, and choose the capacitance value according to the transmission frequency. The higher the frequency, the lower the capacitance value of the device. If the capacitance value is too large, it will easily cause signal packet loss. Therefore, it must be Choose the most suitable ESD according to your own needs.

　　The ESD protection components to be used in the USB port must meet the following three requirements at the same time:

　　First, the parasitic capacitance of the ESD protection component itself must be small, so as to ensure that data transmission does not lose packets, and does not affect the transmission rate of the USB interface;

　　Second, the protection component must have a high tolerance to ESD, at least able to withstand the bombardment of IEC 61000-4-2 contact mode 8kV ESD.

　　The third and most important requirement is that the clamping voltage provided by the protective component during an ESD event must be low enough to not cause damage to the transmitted data.