CY6611 EZ-USB HX3PD Evaluation Kit Guide, Document Number: 002-26068 Rev *A
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Appendix A: Terminology
A brief description on USB, USB Charging specification, USB Type-C, and USB PD terms are provided for reference.
USB Type-C (Type-C): The new USB connector specification for a slimmer and reversible connector, with extended power
handling capability. The new connector supports latest USB and power delivery specifications. The connector is backward
compatible with the previous USB specifications.
USB PD (USB Power Delivery): A new USB standard that increases power delivery over USB from 7.5 W to 100 W.
Upstream Facing Port (UFP): A USB Type-C port on a device or a hub that connects to a host or the Downstream Facing
Port (DFP) of a hub and a default power sink.
Host: A USB host system such as a PC.
VBUS: A USB Type-C bus wire used for power; initially 5 V, but increased up to 20 V on USB PD systems.
DFP: A USB Type-C port on a host or a hub that connects to a device.
USB 3.1 Gen 2: Latest USB specification that supports a transfer speed of up to 10 Gbps. Also called USB 3.1.
BC1.2 (USB Battery Charging Specification v1.2): The latest version of USB based charging protocol.
SuperSpeed (SS), High-Speed (HS), Full-Speed (FS), Low-Speed (LS): The USB protocol support various transfer speeds.
Low-Speed (1.5 Mbps) and Full-Speed (12 Mbps) were introduced with first version of USB specification (USB 1.1). High-
Speed (USB 2.0) supports a transfer speed of up to 480 Mbps. Super Speed introduced by the USB 3.x specification, supports
5 Gbps (USB 3.1 Gen 1) and 10 Gbps (USB 3.1 Gen 2).
Fast Role Swap (FRS): Ability of a Dual Role Port (DRP) to switch power roles between sink and source. The FRS was
introduced with latest power delivery specification (USB PD v3.0).
Figure A-1: USB Type-C Plug and Receptacle
