'Faster, Higher, Stronger' is a well-known Olympic motto that we all know. If we apply this motto to the electronics industry now, it should be 'Faster, Smaller, and Easier to Use' - this is the call for a new standard for USB connectivity.

You may have seen that the latest USB type c (USB-C) port is widely used in the new generation of computing products currently on sale, and this trend is expected to be further strengthened in the future, as USB-C has the unique ability to transmit data, power, and even audio through a single wired connection.

Market analysis company ABIResearch believes that we have reached the critical point of commercial use of USB type c; By 2021, the global shipment of smartphones equipped with this USB connector is estimated to reach 830 million units.

This type of connector has a width of only 9mm and a height of only 3.5mm, which is much smaller than previous generations of connectors. It allows device manufacturers to develop smaller devices. Its launch can be said to be at the right time, perfectly catering to the needs of emerging products, such as home automation and IoT devices, including smart sensors that can be perfectly matched with this smaller and more concise latest connector packaging.

Cables for USB-C applications can be inserted from any end to meet the power needs of devices such as laptops, eliminating the need for users to carry multiple cables for different purposes.

This universality stems from the more complex structure inside the connector. Firstly, it has more wires. The USB type-A and type-B connectors require four or five wires - unlike them, the USB-C includes 24 contacts, allows bidirectional insertion, and supports four power and ground pairs, as well as two signal pairs. In addition, its rated durability has been increased to 10000 plugins, a significant increase compared to the previous version's 1500 plugins.

The rated voltage of the USB-C power supply and grounding pair is as high as 20V, and the current rating has also increased, with a total rated value of 5A. A single USB-C connection can provide up to 100W of power transmission. In addition, each data pin pair can manage a data transmission rate of up to 10Gbps, which means that the total transmission capacity of the connector reaches 20Gbps.

Faster data and higher power transmission. The latest data and power specifications of USB-IF force us to significantly improve the transmission capacity of USB-C, especially in USB Power Delivery (USB PD), USB 3.1 2nd generation, and recently finalized USB 3.2 high-speed data specifications: USB PD utilizes all four power and ground pairs to fully utilize the 100W power transmission capacity of USB-C, USB 3.1 2nd generation utilizes a set of data channels, Similarly, USB 3.2 controls two sets of 10 Gbps data channels and maintains a transmission rate of up to 20Gbps. Conceptually, it is important to distinguish the USB-C standard (only defining physical connections) from USB PD and high-speed data specifications (including USB 3.1 1st generation (SuperSpeed), USB 3.1 2nd generation (SuperSpeed+), and USB 3.2).

For example, although the design of the USB-C connector supports the USB PD standard, it is still necessary to have a USBPD compatible host controller to negotiate and manage power delivery to interconnected devices. In addition, the cables must be configured to support this standard.

USB PD not only increases power, but also facilitates bidirectional power transmission, greatly improving the flexibility of user device charging and power supply. On this basis, since USBPD can negotiate power through VBUS connections instead of using data connections, it can transmit both power and data streams simultaneously. Table 1 shows the improvement process of USB transport capacity in recent generations of products.

In terms of high-speed data specifications, the second generation of USB 3.1 defines data and power signals, but does not specify physical connections. This enables us to use traditional Type-A or Type-B connectors and cables to connect USB 3.1 Gen 2 devices and achieve a data transmission rate of 10 Gbps, as long as they have sufficient current, voltage and Signal integrity characteristics. Similarly, we only need to use a simple hardware adapter to provide traditional connection standards such as USB 2.0 using USB-C connectors.

Obviously, not all USB-C connectors or cable components are 'born equal', and high-quality products can provide better performance and demonstrate more reliable communication capabilities on longer cables.

In addition to considering the materials selected for future products and the quality of USB-C connectors, designers can also choose between two versions of type C interface sockets, as shown in Figure 2. Traditionally, standard SMT installation sockets are located above the PCB. But in this case, the total assembly height is the sum of PCB thickness and connector height. Alternatively, the middle mounted connector can be installed in the recess of the PCB; Although this can reduce the overall assembly height, the middle mounted connector does not allow signal wires to run below the connector.

In the consumer electronics market, the application of USB type-C connectors is rapidly gaining popularity. To meet this continuously increasing demand, electronic component manufacturer CUI offers a series of high-quality USB type C plugs and USB sockets, including SMT and intermediate installation types. The design purpose of these connectors is to achieve the communication rate defined in the USB3.1 second-generation specification, while meeting the current and future needs of designers.