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Page 22 IC502A
Appendix. Technical Glossary
A.1 USB Connectors
USB cables have two classes of connectors. The Type A connectors are used to connect the cable from a USB device to a Type A
port on a computer or hub. The Type B connectors are used to attach the USB cable from a USB host to a USB device or hub.
There are full-sized, mini, and micro variants of both type A and B connectors.
USB 3.0 introduces changes to the connectors. USB 3.0 and USB 2.0 Type A connectors are the same shape and size and are
compatible with each other. However, the USB 3.0 Type B connector will not fit in a USB 2.0 Type B port, though a USB 2.0 Type
B connector will fit into a USB 3.0 Type B port.
Figure A-1. USB connectors.
A.2 Duplex LC Crossover
When a crossover fiber-optic cable is needed, the cable has the transmit signal on one end connected to the receive signal at the
other end.