Precision 7550 Service Manual

Universal Serial Bus, or USB, was introduced in 1996. It dramatically simplified the connection between host computers and peripheral devices like mice, keyboards, external drivers, and printers.

USB 3.2 Gen 1 (SuperSpeed USB)

For years, the USB 2.0 has been firmly entrenched as the de facto interface standard in the personal computer 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 3.0/USB 3.1 Gen 1 finally has the answer to the consumers' 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 20 Gbps).
• Increased multilane operation of 10 Gbps each.
• 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 compatibility with USB 3.1/3.0 and USB 2.0.
• New connectors and cable.

The topics below cover some of the most commonly asked questions regarding USB 3.0/USB 3.2 Gen 1.

Speed

Currently, there are five speed modes that are defined by the latest USB 3.0/USB 3.1 Gen 1 specification. Based on USB data transfer, they are categorized as Low Speed, Full Speed, High Speed (from version 2.0 of the specification), SuperSpeed (from version 3.0), and SuperSpeed+ (from version 3.1). The new SuperSpeed+ mode has a transfer rate of 20 Gbps. The USB 3.2 standard is backward compatible with USB 3.1/3.0 and USB 2.0.

USB 3.2 Gen 1 achieves the much higher performance by the technical changes below:

Applications

USB 3.1 Gen 1 opens up the laneways and provides more headroom for devices to deliver a better overall experience. Where USB video was barely tolerable previously (both from a maximum resolution, latency, and video compression perspective), it is easy to imagine that with 5 to 10 times the bandwidth available, USB video solutions should work that much better. Single-link DVI requires almost 2 Gbps throughput. Where 480 Mbps was limiting, 5 Gbps is more than promising. With its promised 4.8 Gbps speed, the standard finds its way into some products that previously were not USB territory, like external RAID storage systems.

Listed below are some of the available SuperSpeed USB 3.0/USB 3.1 Gen 1 products:

Compatibility

The good news is that USB 3.2 Gen 1 has been carefully planned from the start to peacefully co-exist with USB 2.0. First of all, while USB 3.2 Gen 1 specifies new physical connections and thus new cables to take advantage of the higher speed capability of the new protocol, the connector itself remains the same rectangular shape with the four USB 2.0 contacts in the exact same location as before. Five new connections to receive and transmit data independently are present on USB 3.0/USB 3.2 Gen 1 cables and only come into contact when connected to a proper SuperSpeed USB connection.