Dell Latitude 7410 Chromebook Service Manual - Page 16

USB 3.2 Gen 1 Super-Speed USB, Speed, Backward USB 2.0 compatibility

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USB 3.2 Gen 1 (Super-Speed USB) For years, the USB 2.0 has been firmly entrenched as the de facto interface standard in the PC world with about 6 billion devices sold, and yet the need for more speed grows by ever faster computing hardware and ever greater bandwidth demands. The USB 3.2 Gen 1 finally has the answer to the consumer's demands with a theoretically 10 times faster than its predecessor. In a nutshell, USB 3.2 Gen 1 features are as follows: ● Higher transfer rates (up to 5 Gbps) ● Increased maximum bus power and increased device current draw to better accommodate power-hungry devices ● New power management features ● Full-duplex data transfers and support for new transfer types ● Backward USB 2.0 compatibility ● New connectors and cable The topics below cover some of the most commonly asked questions regarding USB 3.2 Gen 1. Speed Currently, there are 3 speed modes that are defined by the latest USB 3.2 Gen 1 specification. They are Super-Speed, Hi-Speed, and Full-Speed. The new Super-Speed mode has a transfer rate of 4.8 Gbps. While the specification retains Hi-Speed, and Full-Speed USB mode, commonly known as USB 2.0 and 1.1 respectively, the slower modes still operate at 480 Mbps and 12 Mbps respectively and are kept to maintain backward compatibility. USB 3.2 Gen 1 achieves the much higher performance by the technical changes below: ● An additional physical bus that is added in parallel with the existing USB 2.0 bus (see the figure below). ● USB 2.0 previously had four wires (power, ground, and a pair for differential data); USB 3.2 Gen 1 adds four more for two pairs of differential signals (receive and transmit) for a combined total of eight connections in the connectors and cabling. ● USB 3.2 Gen 1 utilizes the bi-directional data interface, rather than USB 2.0's half-duplex arrangement. This gives a 10-fold increase in theoretical bandwidth. With today's ever increasing demands that are placed on data transfers with high-definition video content, terabyte storage devices, high megapixel count digital cameras etc., USB 2.0 may not be fast enough. Furthermore, no USB 2.0 connection could ever come close to the 480Mbps theoretical maximum throughput, making data transfer at around 320 Mbps (40 MB/s) - the actual real-world maximum. Similarly, USB 3.2 Gen 1 connections will never achieve 4.8Gbps. We will likely see a real-world maximum rate of 400 MB/s with overheads. At this speed, USB 3.2 Gen 1 is a 10x improvement over USB 2.0. 16 Technology and components

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USB 3.2 Gen 1 (Super-Speed USB)
For years, the USB 2.0 has been firmly entrenched as the de facto interface standard in the PC world with about 6 billion
devices sold, and yet the need for more speed grows by ever faster computing hardware and ever greater bandwidth demands.
The USB 3.2 Gen 1 finally has the answer to the consumer's demands with a theoretically 10 times faster than its predecessor. In
a nutshell, USB 3.2 Gen 1 features are as follows:
Higher transfer rates (up to 5 Gbps)
Increased maximum bus power and increased device current draw to better accommodate power-hungry devices
New power management features
Full-duplex data transfers and support for new transfer types
Backward USB 2.0 compatibility
New connectors and cable
The topics below cover some of the most commonly asked questions regarding USB 3.2 Gen 1.
Speed
Currently, there are 3 speed modes that are defined by the latest USB 3.2 Gen 1 specification. They are Super-Speed, Hi-Speed,
and Full-Speed. The new Super-Speed mode has a transfer rate of 4.8 Gbps. While the specification retains Hi-Speed, and
Full-Speed USB mode, commonly known as USB 2.0 and 1.1 respectively, the slower modes still operate at 480 Mbps and 12
Mbps respectively and are kept to maintain backward compatibility.
USB 3.2 Gen 1 achieves the much higher performance by the technical changes below:
An additional physical bus that is added in parallel with the existing USB 2.0 bus (see the figure below).
USB 2.0 previously had four wires (power, ground, and a pair for differential data); USB 3.2 Gen 1 adds four more for two
pairs of differential signals (receive and transmit) for a combined total of eight connections in the connectors and cabling.
USB 3.2 Gen 1 utilizes the bi-directional data interface, rather than USB 2.0's half-duplex arrangement. This gives a 10-fold
increase in theoretical bandwidth.
With today's ever increasing demands that are placed on data transfers with high-definition video content, terabyte storage
devices, high megapixel count digital cameras etc., USB 2.0 may not be fast enough. Furthermore, no USB 2.0 connection could
ever come close to the 480Mbps theoretical maximum throughput, making data transfer at around 320 Mbps (40 MB/s) —
the actual real-world maximum. Similarly, USB 3.2 Gen 1 connections will never achieve 4.8Gbps. We will likely see a real-world
maximum rate of 400 MB/s with overheads. At this speed, USB 3.2 Gen 1 is a 10x improvement over USB 2.0.
16
Technology and components