Understanding USB Specifications for Selecting the Correct Cables, Plugs, and Jacks

USB (universal serial bus) cables, connectors, and jacks are used in a wide variety of industrial applications, such as industrial sensors, control modules, digital signage, point-of-sale terminals, and much more. The key to incorporating the right product for an application is to remember that different generations of USB devices directly affect performance.

USB has long been the standard for connecting everything, including keyboards, mice, cameras, phone chargers, computers, and wall adapters. These connectors are used to transfer data and power between devices. Early USB cables and connectors could only transfer data at slow speeds of up to about 12 Mbps, until the year 2000 when the USB 2.0 was introduced. That is when the drive toward higher device speeds began to grow quickly.

In this article, the necessary detailed knowledge of the different types of USB connectors and cables, as well as their capabilities, will be discussed to provide the information needed to make the right selection for a specific application.

USB versions and their capabilities

USB 2.0 offered 480 Mbps to its users, a speed increase over 40 times the original USB offering in the 1990s, which could only handle 12 Mbps. The newer version was designed with four connector wires and could interconnect devices with cable lengths up to 30 meters (98 feet). Although they were considered capable of high-speed data transfer, these cables could not support video. The connectors and cables could support power with up to 500 mA of current, whereas the older version could not. The four-wire cable used white and green wires for data transfer, while red and black wires were used for power — red for 5 volts and black for ground. USB 2.0 can easily be identified by the black interior of the connector port. These updated USB capabilities allowed for greater flexibility in multiple applications at the time and are still relevant today.

Eight years after the introduction of the USB 2.0, the USB 3.0 became available. The 3.0 version provided users with even higher data speeds — 10 times higher, to be exact — and are considered SuperSpeed devices. These cables and connectors can support video data transfers. The USB 3.0 cables and connectors were designed to transfer data at speeds of 4,800 Mbps (nearly 5 GB). This super-fast transfer speed rate came in handy when used for backing up or transferring large amounts of data to and from a hard drive or controller. The additional wires are used to provide two-way communications simultaneously. Professional photographers are keen on using USB 3.0 connectors due to their need to transfer high-resolution images between multiple devices as well as uploading to high-speed network computers.

The 3.0 USB version was faster but could only be interconnected to devices within an 18-meter (59-foot) cable length. The unit’s nine-wire connectors, instead of the USB 2.0’s four-wire connectors, provided the right environment for the increase in speed and bandwidth the devices were required to handle. The technology also allowed the cables and connectors to be compatible with up to 900 mA of current, plus provided greater power efficiency for use with power-hungry devices.

Note that the USB 2.0 standard version connectors and USB 3.0 standard connectors provide radically different specifications. Be sure to match an application to the specific capabilities of the USB connectors and cables you plan to incorporate. USB 2.0 connectors can be recognized because USB 2.0 ports are black, while USB 3.0 ports are blue. USB 3.0 devices are backward compatible and will work with other USB versions, such as USB 2.0. However, the connection will be limited to the maximum speed of the USB 2.0. By about 2012, USB 3.0 was used on all new computers and became a manufacturing standard. These devices can be found in most industries that use USB cables to connect everything from sensors and transducers to data hubs, controllers, and computers.

USB cables and cord assemblies

A full offering of USB cables and cord assemblies is available in multiple configurations and combinations from GlobTek, Inc., including nonstandard configurations based on a customer’s specific application requirements.

Their entire line of USB cable assemblies meets USB 2.0, USB 3.0, and/or USB 3.1 standards and comes in a wide variety of shielded and unshielded lengths. Additional cable connector options are also available, such as DC power plugs and blunt cut or stripped and tinned terminations. Cable assemblies are sheathed in either PVC or a TPE, halogen-free jacket material. In addition, customized USB connector overmolds with additional features are also available upon request.

For cable and cord assemblies, GlobTek, Inc. provides a wide variety of lengths from 100 mm and longer, as well as multiple colors for use in sensitive equipment where quick visual identification is a definite plus. Many off-the-shelf products are available with standard terminations, plugs, and receptacles already installed.

USB Types have specific uses in most commercial and industrial settings. For example, USB Type-A are used with power outlets and computers for charging devices. Since these connectors and cables, such as the USBA2C1MOUSBCR shown in Figure 1, only go into the device port one way, users cannot easily connect them incorrectly. USB Type-B ports are often used to connect peripheral devices — such as printers, scanners, and external hard drives — to a computer or controller. These connectors are not as common as those used for general use.

Figure 1: Shown is the USBA2C1MOUSBC(R), a USB 2.0 Type-A male plug to Type-C male plug incorporating a 1.00 meter unshielded cable. USB Type-A connectors can only go into the device port one way, so users cannot connect them incorrectly. (Image source: GlobTek, Inc.)

Products such as the USBCM302M0MICBMMBKR, shown in Figure 2, are used for mobile devices, such as cell phones, tablets, MP3 players, and cameras, as well as portable meters or control units used in industrial settings. The USB Type-B micro allows data to be read without being connected to a computer in applications such as flash drives or memory sticks connected directly to a device. Similar to the Type-A connectors, these devices only go into a port one way and can be damaged if not done so.

Figure 2: The USBCM302M0MICBMMBKR, USB Type-B micro male plug to Type-C male plug with 2.00 meter shielded cable shown, is often used to connect devices directly to flash drives or memory sticks without needing to connect through a computer. (Image source: GlobTek, Inc.)

The newest connector device is the USB Type-C. These connectors and cables, such as the USBCM311M0USBCMMMWHR shown in Figure 3, are designed specifically for high-speed data transfer and higher current flow, allowing devices to charge more quickly. Unlike other USB Type connectors, the USB Type-C can be plugged into a device in either direction.

Figure 3: The USBCM311M0USBCMMMWHR is a shielded, 1-meter-long, USB-C male to USB-C male cable capable of handling 10Gbps data rates. (Image source: GlobTek, Inc.)

Conclusion

USB connectors and cable assemblies are an integral part of everyday life. These assemblies have made it into almost every home to interconnect laptop and desktop computers to multiple peripherals, as well as for connecting mobile phones and tablets to power sources. USB components are also used in automation, where high-speed data transfer between computers and remote sensors and transducers is essential. GlobTek’s certifications and commitment to quality position them as a dependable source capable of meeting the demands of consumers and manufacturers alike.