USB has been around for nearly twenty years and for the past fifteen years has been a staple of computer communications. It has replaced a host of different serial ports and is the de facto standard to plug nearly anything into a computer. Through the years, USB has been upgraded in speed and has had several very popular variants. However, the standard-A USB port has been the same from the beginning. This sturdy plug was extremely small for its time; it provided decent performance, was hot pluggable, had good data transfer rates and could power very small devices. For the mid 90's, this plug was impressive. However, the most powerful supercomputer of 1996 is now less powerful than most video cards, so times change. And the USB port is getting a massive overhaul with the Type C connectors.
Benefits of USB-C
There are many things that separate Type C from any of the prior USB connectors, reversibility being the most obvious one. Type C plugs don't have an up and down, so there's no fumbling behind desktops or peering at the end of the cable and port trying to figure out which way the plug needs to be inserted. The benefits of this are fairly obvious and should lead to a lot less frustration when it comes to dealing with the plugs. Another benefit of the USB-C is the end-to-end reversibility. Whereas most USB cables are Type A on one end and practically any other type on the other end, Type C is designed to have the same plug on both ends, though designers may make exceptions for interfacing with legacy connectors.
Before, this wasn't practical because Type A was great for computers but much too big for smaller handheld devices, such as phones. Now, as desktops are becoming increasingly rare and laptops or tablets are taking their place as the new norm, a small USB connector on both ends is practically a requirement. During the transition period, this may be problematic and frustrating as a converter will be needed to connect a Type C USB to anything electronic. Once the transition is over, the result is all USB products will use the same cord. From an optimist's point of view, it is convenient the Type C is backwards compatible, needing only a converter to still utilize those soon-to-be legacy devices.
Related: Learn about USB Type-C Plug and receptacle pinouts.
What is the difference between USB-A and USB-C?
Looking down the end of a Type A, four metal contacts can be seen. These contacts are the power, ground, D+ and D-, the last two being the differential data lines. The Mini- and Micro- introduced an extra contact used for establishing the ID of on-the-go USB devices. Type C, however, has 24 different contacts. While 24 may seem a bit excessive, it makes sense. To allow the cable to be reversed, there are two contacts that specifically identify the orientation of the cable. These cables are capable of transmitting significantly more power than previous standards, so there are eight contacts dedicated to power and ground. The remaining are dedicated to data transfer lines and other administrative-type contacts. It may seem with this decrease in size and increase in contacts, it would be significantly less robust but the opposite is true. While the Type A is rated for about 1,500 insertion and removal cycles, the Type C is rated for about 10,000 cycles.
Related: Learn more about USB Type A connectors.
USB-C power delivery
The Type C also supports USB 3.0 and above in regards to the power delivery specification, a major improvement in many ways. In sheer quantity, USB ports are now able to transfer up to 100 watts while simultaneously transmitting data. Up to this point, it has been possible to transfer large quantities of power over USB cables but only when they were solely transferring power. Today, that power can be transferred without limiting any other features. This power is bi-directional, allowing it to be transferred in either direction on the cable, not merely from one side to the other. Also, the power transfer is no longer limited to just 5 volts. Using intelligent power management, a device can request different voltage levels and different amounts of current, allowing for extreme design flexibility.
Transmitting video with Type C cables
Due to the multitude of data lines in the Type C cables, they are capable of transmitting data and video simultaneously. This has been shown in demos by transferring data through the cable, having that data processed and returned as a video through the same cable. This is particularly impressive as the video doesn't stutter or have any strange artifacts, acting much like a dedicated video cable. This capability has led to the inclusion of only a single Type C USB port in Apple's newest MacBook Pro. As the cable can handle power, data transfer and video; this single port is capable of plugging into a hub that will allow for multiple peripherals and additional monitors while also charging the laptop. Again, impressive.
USB-C industry standards
The USB standards are established by a conglomerate of industry giants who want to use these connectors, but anyone can manufacture them. This is beneficial, as it creates a competitive marketplace of manufacturers who vie to create not only the best connectors but also the supporting ICs. There is a downside to this competitive marketplace, however. As most consumers are not aware of the underlying principles behind the cable, there are manufacturers who create products that fit the physical appearance of the connector but not the performance standards. These manufacturers sell the connectors and cables under the name of Type C USB 3.1 compatibility but don't actually provide the performance advertised. Therefore, it is critical that engineers choose a reputable manufacturer like Amphenol who have tested and verified that their USB Type C products are fully compliant to the latest industry standards.
Type C connector shielding
Above and beyond the requirements of Type C connectors, Amphenol also uses an integrated shielding design which improves the signal integrity while providing greater protection from EMI. While even casual users in their homes will likely see improvements from this, the shielding is particularly helpful in business, industrial and scientific work. The shielding decreases the effect of the incredible amounts of EMI generated in those working conditions, making the work environment less cluttered in the electromagnetic spectrum.
USB-C connections
Proper USB-C connections are essential for both robust physical and electrical performance. Electrically, higher frequency signals suffer from resonance within the connector system if discrete ground paths are used. To counter this, all grounded parts in the system such as pins, the EMC sheet and the latch are all directly connected reducing the amount of resonance in the connector system, once again reducing EMI interference as well as crosstalk. Physically, Amphenol laser welds the outer, inner and EMI shell together to make them stronger. This is in comparison to most manufacturers who mechanically connect the different pieces together making them more prone to failure from either repeated use or accidental abuse. Finally, where some manufacturers use cheap and brittle plastic for the connector housing, Amphenol uses a special wear-proof resin that significantly increases the durability and ensures they perform above the industry standard.
While Type C and USB 3.1 have direct competition, these significant improvements to a product with an overwhelming amount of market share inspires considerable confidence that these cables will become the de facto standard in computer and portable connectivity. While the standard has impressive performance, you can rest assured, when you buy Amphenol, the quality of the components will always meet or exceed your expectations.
About: Amphenol Commercial Products (ACP) is an international leader in providing interconnect solutions for a wide range of markets and applications from traditional connectors to the latest, next generation technology.
