USB connectors and cables

USBconnectors

Thereare two types of full-size USB connectors: Series-A andSeries-B, also known as Type-A and
Type-B,respectively. Either connectortype can be a receptacle or a plug.
lSeries-Areceptacles are usedas outputs from host systems and hubs.
lSeries-Breceptacles are usedas inputs to hubs or devices.
lSeries-Aplugs are always orientedtoward the host sys tem andconnect to Series-A
receptacles.
lSeries-Bplugs are always orientedtoward a USB hub or device and connect to Series-B
receptacles.
NO T E
Smallerversions of the Series-A and Series-Bconnectors, called mini-A and mini-B, andmicro-A
andmicro-B, are availableand conform to the same rules as full-size USB connectors.
TI P
AlthoughUSB 2.0 specifications requirethat USB connectors can be“hot plugged”(for example,
youc aninsert a US B connectorwit h poweron without damaget o the circuitry), we recommend
that you connectall y ourdevices and cables beforey out urnon the power. If you connect a device
whenthe power is already on, andthe sy stem doesn’t work correctly, disconnect the powerfrom all
active devices in the USB circuit, andt henconnect the power again.
AP P E N DI X A
USB2.0 specification primer
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