USB 3.1 Gen2 is the latest USB specification, which was initiated by Intel and other companies. The data transmission speed can be increased to 10Gbps. Compared with USB 3.0 (i.e. USB 3.1 Gen1), the new USB technology uses a more efficient data encoding system and provides more than twice the effective data throughput. It is fully downward compatible with existing USB connectors and cables. USB 3.1 Gen2 is compatible with existing USB 3.0 (i.e. USB 3.1 Gen1) software stack and device protocol, 5Gbps hub and device, USB 2.0 products.
It is the mainstream connector which applied in our USB C HUB line.
Some definition about USB various generation connector
USB 3.1, USB 3.1 Gen1 is USB 3.0. USB 3.1 Gen2 is the real USB 3.1.
 The maximum transmission bandwidth of USB 2.0 is 480 Mbps (60MB/s).
 The maximum transmission bandwidth of USB 3.0 (i.e. USB 3.1 Gen1) is 5.0 Gbps (500MB/s).
 The maximum transmission bandwidth of USB 3.1 Gen2 is 10.0 Gbps (although the nominal theoretical interface rate of USB 3.1 is 10 Gbps, it retains some bandwidth to support other functions, so its actual effective bandwidth is about 7.2 Gbps).
USB 3.1, as the next generation of USB transmission specifications, is commonly referred to as “SuperSpeed+”, which will replace USB 3.0 in the future.
USB 3.1 has three connection interfaces, namely Type-A (Standard-A), Type-B (Micro-B) and Type-C.
Standard Type-A is the most widely used interface at present, while Micro-B is mainly used for devices such as smart phones and tablets, while the newly defined Type-C is mainly for lighter, thinner devices.
Type-C greatly reduces the physical appearance and is more suitable for short and light hand-held devices. Type-C will replace Micro-A/B connectors (which support USB devices to transmit directly without the intervention of the main control system) and general micro-USB connectors. Type-C will imitate Apple Lightning connectors. Both positive and negative can be connected properly. Compared with the existing Micro-USB, Micro-USB has anti-back wiring mechanism, but both positive and negative benefits are better than anti-back wiring. In addition, Type-C also has enhanced EMI and RFI mitigation characteristics.
Type C Pin Assignment
Transfer speed and codes
In response to the high-speed applications of various devices, the bandwidth of USB has been greatly improved from 1.0 version (1.5 Mbps), 1.1 version (12 Mbps), 2.0 version (480 Mbps) to 3.0 version (5 Gbps). In the face of future demand, the new USB 3.1 interface will double the bandwidth again to 10 Gbps. At the same time, it is worth noting that the bandwidth of USB 3.1 interface will be increased to 10 Gbps. The coding rate has also increased again.
USB 3.0 encodes 8b10b, that is to say, only 8bit is the real data in every 10bit data transmission, and the remaining 2bit is the check code, so the whole bandwidth will be as high as 20% (2/10) loss, while the new USB 3.1 uses 128b/132b code, in 132bit data, only 4bit is used as the check code, transmission loss rate. USB 3.1 not only improves the bandwidth, but also improves the transmission efficiency. In addition, compared with Thunderbolt, USB 3.1 and Thunderbolt 1 already have the same speed of 10 Gbps, while Thunderbolt 2 provides 20 Gbps, but only merges two independent 10 Gbps in the original Thunderbolt 1 into one-way transmission of 20 Gbps instead of two-way transmission. In this view, as long as the USB 3.1 device is officially on the market, the bandwidth speed will increase. It still has considerable advantages in application scope.
Compared with 5V/0.5A of USB 2.0, USB 3.0 provides 5V/0.9A power supply. But people still want more power supply, so USB 3.1 (SuperSpeed+) has raised the maximum allowable standard of power supply to 20V/5A, power supply 100W.
Power Supply Specification – USB Power Delivery (USB PD), designed to be compatible with existing USB 2.0 and USB 3.0 wires and connectors, and new USB 3.1 Type-C connectors are also universal. USB PDs support higher voltage and current to meet different application devices, while also compatible with existing USB Battery Charging 1.2 charging specifications. USB PD is a port-to-port architecture. USB and power communication signals are separated. Power supply is communicated through VBus communication protocol between host and device. If the device supports, it can provide higher wattage supply according to the voltage and current of Profiles. USB PDs are divided into five configurations (Profiles) according to the device. New detectable wires are needed to provide power larger than 1.5A or 5V. Configuration 1 for mobile phones, 5V/2A (10W), basic power output is more than 5V/0.9A (4.5W) of USB 3.0; Configuration 2 is 5V/2A or 12V/1.5A (maximum value), which can charge tablets and pens; Configuration 3 is 5V/2A or 12V/3A (which can provide the largest 36W power for larger pens); Configuration 4 is 20V/3A (60W) (Micr). O-A/B connector is not supported). Configuration 5 is the maximum power supply of 20V/5A (100W), (TYPE-A/B connector is not supported). That is to say, only type-C can fully support the maximum power supply of 100W. The upgrading of USB 3.1 power supply and the application of charging support will make USB 3.1 hopeful for a unified mobile phone, tablet and computer transmission interface.
USB 3.1 adds USB A/V audio and video transmission; it is very convenient to use USB to transmit pictures. In addition to the wide range of USB interface itself, it can also save a power line and directly supply power by USB, such as ASUS MB168B + 15.6 inch portable display, which is connected by a USB 3.0, but it only supports Full at most. HD level. The new USB AV 3.1 provides 9.8 Gbps bandwidth, supports 4096 x 2304 @ 30FPS 4K display screen, 4K display specifications have been the same as HDMI 1.4, while USB AV also supports HDCP image encryption technology, with a larger power supply, larger size display is expected to display 4K resolution through USB AV 3.1. In addition, existing devices and monitors can transmit video and audio via USB AV adapter via USB cable. If USB AV can be popularized, it will certainly bring a lot of convenience to life. USB cable may replace other display interfaces and become the most practical audio and video transmission wire. Exceptions Because of the powerful TYPE C interface function, the popularity will be higher and higher. At present, there are many TYPE C series products on the market that support full-function, which will drive the updating and upgrading of related supporting products. Now the market demand for the HUB series has obviously begun to magnify, the future can be expected!
Post time: Aug-12-2019