In recent years, many electronic products have been designed to be light, thin, and compact that allows the widely used Type A connector to be replaced by Type C connector. Type C has a symmetrical structure, so it can be docked front and back by small connectors. There are a total of 24 pins (Figure 1) that are symmetric to the top and bottom of the connector. In addition, the Type C can support up to 100W when charging, which is enough to power a large-sized notebook; hence, the charging speed is greatly improved. At the same time, Type C can also support two-way charging. Type C transmission cable not only can help the mobile phone charge, but also allows other devices to be charged by the mobile phone through the transmission cable. As for the transmission speed, in order to meet the current transmission requirements to save time, Type C transmission speed is faster than USB2.0, even faster than USB3.1 Gen1. The maximum speed can reach 10Gbps and the highest voltage value on VBUS is 20V. It is not only for the 5V products, but also directly for a lot of higher voltage terminal products, improving the quality and convenience of life.
Figure 1. USB Type C Receptacle Interface
As the current process is more and more advanced, the protection against electrostatic discharge is getting weaker and weaker. Because the protection of electrostatic discharge is proportional to the area, people nowadays pay more and more attention to the problem of electrostatic discharge. With the current changes in consumer usage and habits, a laptop can be charged at the same time and connected to a flash drive, an external hard drive, etc. In the normal operation of the notebook, the plug-and-play and pull-to-off is easy to cause a hot plug.
In hot plug, since the signal line at the interface end is already charged (the wire will accumulate charged energy inside through the friction). When contacting with the electronic product, a large amount of energy is instantaneously released. This phenomenon is Electrostatic Discharge (ESD) or Electrical Over Stress (EOS), which can cause the electronic system to work abnormally, damaged USB connector, and even crashes. Therefore, this kind of cost is relatively high, so many electronic products are now specifically tested for the hot-plug requirements as strict ESD protection test standard, in which directly applying Pin-Direct Injection to test ESD is the most rigorous. This method is used to simulate the electrostatic discharge of the system when it is used by the client. As long as the appropriate ESD/EOS protection components are added to the USB port during design, the protection work can be done beforehand to avoid damage or crash of the finished products, preventing high cost of loss. It can also reduce the problem of customer’s return of products and improve the image of the company's brand.
AMAZING Microelectronic Corp. has advanced electrostatic discharge protection design technology. To meet the protection requirements of Type C, the electrostatic discharge protection component AZ176S-04F is developed. The parasitic capacitance of the AZ176S-04F pin is 0.29pF, and it can withstand the IEC61000-4-2 system level contact mode 14kV electrostatic discharge bombardment without reducing any transmission speed and causing damage. Most importantly, the AZ176S-04F has a very low clamping voltage, which can effectively prevent the transmission of data errors, crashes or damage during system electrostatic discharge testing. In the IEC61000-4-2 contact mode 8kV ESD shock (equivalent TLP current is about 16A), the clamping voltage is only 4.3V. In addition, the AZ176S-04F utilizes a feed through to protect the line, which has the advantages of reducing the area of the PCB and reducing the complexity of the layout. Figure 2 shows the wiring of the
Figure 2, The wiring method of AZ176S-04F
At present, AZ176S-04F and AZ1023-04F are new Type C products of AMAZING Microelectronic Corp. They have low capacitance, low clamping voltage and optimal layout design. They are all DFN2510 Array packages, which can be selected according to customer requirements. Even USB 3.2, which is not widely available on the market can be used as a component for electrostatic discharge protection. AMAZING Microelectronic Corp. will actively utilize semiconductor process technology to develop products that meet the needs of the market, allowing customers to achieve maximum performance at the lowest cost, and continue to develop more advanced protection design technology to meet the latest market demand.
Figure 3. USB3.1 Gen2 Type C New Products from AMAZING Microelectronic Corp.