In the early days, traditional USB connectors were mainly used for data transmission in the PC field. However, with the introduction of USB Type-C connectors, they now support a higher power charging rate, which has made USB Type-C connectors a mainstream charging connector for various electronic products such as smart phones and home automation devices. This article will show you the technical development of USB Type-C connectors and the power-only USB Type-C connector solution from CUI Devices.
Evolving USB connector standards
USB connectors were introduced in the mid-1990s. At first, data transmission was the main function. It had a charging capability of 2.5 W/5 V 500 mA. Since then, USB connectors have continuously developed in terms of size, shape, data transfer capabilities, and power constraints. Nowadays, the latest physical standard is Type-C. Besides supporting greater bandwidth, bi-direction and reversibility, this latest iteration can provide higher power transfer than previous generations of products.
There are three different associated standards for USB connectors, including physical connectors, data transmission protocols, and power delivery. At a high level, USB Type-C connectors follow the physical connector standard, which is designed to meet the power delivery standard of up to 240 W, opening up a new opportunity field for USB power application.
The development of USB power levels can range from 2.5 W/5 V 500 mA for USB 2.0, 4.5 W/5 V 900 mA for USB 3.0/3.1, 7.5 W/5 V 1.5 A for USB BC 1.2, 15 W/5 V 3 A for USB Type-C 1.2, and 100 W/20 V 5 A for the latest USB PD 3.0, which is at present the mainstream connector for high-power applications. The latest USB PD 3.1 standard has even further increased power capabilities up to 240W/ 48 V 5 A.
Attractive standardized USB Type-C connectors
The standard USB Type-C connector houses 16 data transfer pins, 4 power pins, and 4 ground pins, for a total of 24 pins. With a power capacity of up to 100 W, USB Type-C is now a viable option for many applications that require high power, and can replace the standard DC power connector even when data transfer is not required.
The biggest benefit of using USB as a power delivery method is standardization, because USB connectors are ubiquitous and are gaining rapid momentum in popularization in the transition to Type-C. At present, many new mobile phones and mobile devices have been equipped with USB Type-C. In addition, it is increasingly possible for the European Union to adopt Type-C connectors as the charging standard for all devices in the future, requiring many different products to use a single and off-the-shelf cable type to provide more convenience and be very attractive to end users.
In addition, from the OEM standpoint, including power only connectors and data + power connectors, these connectors can be easily found through a stable supply chain, because standardization ensures a certain level of interoperability. The standard also ensures easy design and integration, and Type-C occupies a much smaller footprint than many barrel connectors. In addition, USB Type-C connectors have robust characteristics, offering up to 10,000 mating cycles, ensuring a long useful life, making them the mainstream choice among current connectors.
The power only USB Type-C connectors for charging or power supply
Because of the aforementioned benefits in the USB Type-C connector, a power only USB Type-C receptacle was also introduced into the market, which is only used for charging or a power delivery design. 16 data transfer pins and 2 ground pins are removed from these 60 W power only USB Type-C receptacles, and only 4 power pins and 2 ground pins are left.
Since the design of the connector itself is simplified and only 6 pins are used instead of the standard 24 pins, this significantly reduces the cost of the connector. In addition to reduction of part costs, it reduces complexity and failure rates by eliminating most of the pins and associated solder points. Although these power only connectors cannot be used to transfer data, they can still work with any standard USB Type-C cable that can transfer data and power, so end users do not need to incorporate additional steps or hardware when interacting with products.
However, since the data transfer pin has been removed, the USB 3.0 power negotiation process will not take place. In this case, the charging device will return to the USB standard power transfer rate of 5 V and 1 A. For all other applications, the connector will work like any other power jack, and the charging will be controlled by the adapter/charging circuit.
While USB Type-C connectors are useful in a wide range of scenarios, sometimes dedicated power options are still a practical solution. For example, if the hard limit is 240 W, Type-C will not work in this condition when higher power is required. In other cases, due to certain design limitations, different footprint or connector sizes may be required, and USB Type-C connectors may be limited by their standardized footprint, size, and specifications when more customized solutions are needed.
The Future of USB Type C
USB Type-C connectors and Power Delivery standards have opened up a new way to look at power management and transmission. Although it is still not the end-all solution, its high-power capability and global standardization make it an excellent choice for many different products. When only power delivery is needed, CUI Devices’ power-only USB Type C connectors are an intriguing solution for engineers due to their lower cost and simplified design integration.
CUI Devices' UJC-HP-3-SMT-TR is a Type-C, 3A, right angle, 6-pin USB Type-C receptacle designed for power-only applications in a horizontal surface mount package with a current rating of 3A and a voltage rating of 20 Vdc. The other UJC-VP-3-SMT-TR is a 6-pin USB Type-C receptacle designed for power-only applications in a vertical surface mount package with a current rating of 3 A and a voltage rating of 20 Vdc.
Both USB Type-C receptacles make it a more cost-effective solution by removing the data transfer pins, and are suitable for designs where charging or power supply is the only function. In addition, these USB Type-C receptacles are compatible with any standard USB Type-C plug, integrating the accessibility and simplified design of universal Type-C connection for power-only applications, and are compatible with reflow solder and tape & reel packaging.
Conclusion
After years of evolution, USB connectors have become a common connector across computers, communications, and consumer electronic products, and USB Type-C connectors have become a standardized connector for high-power charging applications. The 60 W power only USB Type-C receptacles introduced by CUI Devices make them a more cost-effective solution by removing the data transfer pins, which will be the best choice for designs where charging or power supply is the only function.
관련 상품 참조
