What is USB Type-C?
USB-C represents the next generation of Universal Serial Bus (USB), an industry standard that offers specifications for the cables and connectors that are used to connect peripheral devices to computers, facilitate data transfer, and charge mobile devices, laptops, and tablets.
When USB 1.0, the first generation of USB, was released in 1996, a lack of standardization in communication protocols for peripheral devices made hardware incompatibility a common problem. Computers needed one type of port to connect a mouse, another type of port to connect a printer, another to connect a monitor, and another type to support a keyboard. With the introduction of USB 1.0, all of these mismatched ports could be replaced with a single connector type: USB, and manufacturers had a consistent standard to follow when designing charging cables and connectors for computer peripheral devices.
USB Type-C is the latest iteration of the USB connector. Although the specifications for USB-C were first published in 2014, the standard has grown in popularity over the past year, having been included in several high-profile consumer products. USB-C uses a new reversible connector design with 24 pins and full-duplex communication capabilities.
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USB Offers a Universal Standard for Manufacturers
The release of the USB 2.0 standard coincided with a period in smartphone development where devices were getting progressively smaller with each newly released generation. Manufacturers wanted to continue using the original USB Type A 4.5 mm port, but devices were being designed that were too small to fit the port. As a result, we got innovations like USB Mini B with its 3.00 mm port and later, micro-B with the 1.8 mm port.
Many manufacturers in the past decade have built computers, tablets, and mobile phones based on the USB protocol. Some manufacturers, most notably Apple, designed their own proprietary cable connectors, but they’re still utilizing USB data. One of the major benefits that consumers will see in electronics as a result of the adoption of the USB-C standard is more universal compatibility and more hardware manufacturers building devices that conform to the USB-C standard. Manufacturers not only recognize the benefits and improved operation of USB-C, but there are benefits for consumers when many types of devices can be charged or accessed with the same connectors.
USB Will Replace Other Existing Connection Methods
USB was first established as a complement to FireWire technology, although it operated at a lower data transfer rate and used less sophisticated hardware than the high-bandwidth IEEE 1394 technology that was available at the time.
Other manufacturers have created their own proprietary connectors, with many developing products that are particularly suited to their area of industrial application. Intel created its own communication/connector cable protocol called the Thunderbolt that was designed for users to connect peripheral devices such as a mouse, keyboard, and monitors, to a computer. Apple designed the Lightning charge cable specifically to supply power and facilitate data transfer for low-power accessories.
What USB-C offers that these other standards don't is true versatility and compatibility across devices. The USB-C standard is a viable modern solution for data transfer, cable charging applications, and connecting peripherals - it includes features that make it effective at all three. As a result, an increasing number of manufacturers are adopting USB-C.
USB Type-C Offers Diverse Functionality for Charging and Data Transfer
USB Type-C uses a 24-pin USB connector system that is only slightly larger than a USB micro-B connector, its port measuring 8.4 millimeters wide by 2.6 millimeters tall. The 24-pin configuration supports several alternate usage modes for USB Type-C, including backward compatibility with USB 2.0 for data transfer speeds of up to 480 Mbit/s. In the USB 3.0/3.1/3.2 usage modes, two or four high-speed links are used in TX/RX pairs, providing up to 20 Gbit/s of data throughput.
There are currently four Alternate Mode partner specifications in existence for USB Type-C, with a fifth on its way, having been announced in July of 2018. The DisplayPort 1.4 communication protocol was designed to facilitate DisplayPort Alternate Mode while leveraging the capabilities of the Type-C port. DisplayPort allows users to transmit video images from their computer to another monitor using the SuperSpeed bus on the USB-C connector. The resultant high data transfer speeds mean high quality feeds and less lag for users. Alternate use modes have also been specified for HDMI, Thunderbolt, and Mobile High-Definition Link.
The USB Power Delivery specification introduces commands for changing a port’s power or data functionality once a connection has been made between a host and target device. With this protocol in effect, the user can choose whether to use their Type-C cable for data transfer or to charge a device. When the charge option is selected, USB Power Delivery uses the designated CC1 or CC2 pin to negotiate more power from the host device – up to 20 V at 5 A.
It is important to note that the speed, power, and capabilities associated with USB come from the protocol specification used to transmit data, broadcast audio or video, or charge a connected device. USB Type-C provides a diverse hardware platform that supports many useful protocol specifications that serve versatile functions for users. For embedded engineers, the higher-powered cable carries with it an increased risk of fire in a malfunction. An advanced cable tester should be used to verify that your USB Type-C cable is reliable and safe for operation.
USB Type-C Offers a Reversible Design
Possibly the most exciting, yet underappreciated aspect of USB Type-C is its reversible design. We have all had the experience of plugging a USB cable into the port on our computer or charge adapter, only to realize that we're putting it in upside-down. USB Type-C removes this persistent frustration with a connector that features a revolutionary reversible design - it can be plugged in facing either direction and still works exactly the same.
What New Consumer Products are Using USB Type-C?
Major electronics manufacturers are already starting to adopt the USB-C standard for release with new devices. Google released two versions of the Chromebook Pixel in 2013 that included a pair of USB 2.0 ports and a Mini DisplayPort SD/MMC card reader. By 2015, Google had replaced these ports with a couple of USB 3.1 Type-C ports offering 5 Gbit/s data transfer, power charging, and video broadcasting functionalities.
Even the new Nokia 8 Sirocco phone uses USB 3.1 Type-C, but by far the most impactful new products with USB-C technology have been made by Apple. Apple currently offers several products with USB-C ports, including:
- iMac Pro
- All iMac models after and including 2017
- The 2018 Mac mini
- MacBook Pro models after and including 2016
- The 2018 MacBook Air
Even the third-gen iPad Pro 11-inch and iPad Pro 12.9-inch machines are equipped with a USB-C port.
What Does USB Type-C Mean for Embedded Engineers?
For engineers designing embedded systems, the growing popularity of USB Type-C may affect the way you choose to design products in the future. For starters, the connector for USB Type-C measures just 8.25 mm wide and 2.4 mm high, allowing product designers to create even smaller devices that need to incorporate USB. USB Type-C is also support all USB versions: 2.0, 3.0, 3.1, and 3.2. Although devices with the older USB port design won't work with modern connectors, the underlying communication standard remains backward compatible, so older peripheral devices can be used with a modern USB Type-C cable if a physical adapter is used.
Physical adapters can be used to support backward-compatible peripherals, but it is crucial that embedded engineers understand how to test the suitability and quality of a USB adapter for a given task.
Early adoption of USB Type-C may even help embedded designers differentiate their devices and demonstrate to consumers their enthusiasm for new technologies. At the USB Developers Conference in 2015, the USB-IF announced new Type-C interface specifications, including a standardized register set with an I2C or SPI hardware interface, that will make it easier for embedded engineers to incorporate USB Type-C into their designs. Engineers working with SuperSpeed data transfer will also need a SuperSpeed protocol analyzer to streamline diagnostics and debugging.
Summary
USB Type-C is the latest iteration of the USB connector that will introduce more standardization and streamline hardware compatibility across devices. USB Type-C offers many advantages for the consumer, including high-speed data transfer, a high-wattage power supply cable, and a reliable means of connecting peripheral devices to the computer. In addition to these practical benefits, the reversible design of USB Type-C connectors makes them more user-friendly.
While consumers benefit from increased consistency of charging and connective cables between devices, embedded engineers who adopt the USB Type-C standard will benefit from data transfer speeds and charging capabilities much improved over past USB performance.
For the developers who want to know more about about Total Phase products, you can contact us with your questions, as well as request a demo that is specific to your application.