What is TYPE-C
USB Type-C integrates data, power, and video functions into a single connector interface. USB-C can also eliminate the barrel power jack interface from new platforms.
USB Type-C supports USB 2.0 and USB 3.1, while providing alternate (Alt) mode options such as DisplayPort for video functions.
USB Type-C provides 15W of native power supply capability, and with USB PD, it can provide up to 100W (20V/5A) of enhanced power supply capability. The interface enables smaller, thinner, and more powerful connectors, providing data rates of up to 20Gbps. The cable is reversible and flippable, and can connect to the host or client device in either direction.
TYPE-C interface definition
USB Type-C has 4 pairs of TX/RX lines, 2 pairs of USBD+/D-, one pair of SBU, 2 CCs, and 4 VBUS and 4 ground lines.
The role of each TYPE-C pin
- TX/RX: Ultra-high-speed twisted pair (5 to 10Gbps) for transmitting
USB3.1 data VBUS: Main system bus (5V to 20V). - CC1/CC2: CC lines for cable detection, direction, and current
broadcasting. For USB PD, the CC lines can also transmit higher
power levels and alternate modes. Note that one of the CC lines may
become VCONN - SBU1/SBU2: These are low-speed lines used only for alternate mode
and accessory mode. For example, for DisplayPort, AUX+/AUX– is
transmitted on the SBU line. For audio adapter accessory mode, these
lines are used for microphone input and analog GND. - D+/D–: High-speed twisted pair (up to 480Mbps) for transmitting
USB2.0 data.
Three Data Streams (Data Role) of Type-C
(1) DFP (Downstream Facing Port)
Sends data downstream; it is usually the port on the host or hub to which the device is connected. DFP will power VBUS (the power path between the host and the device) and can also power VCONN (power for electronically marked cables). A typical application that includes DFP is a docking station
(2) UFP (Upstream Facing Port)
DFP connected to a host or hub, receiving data from the device or hub. This type of port usually draws power from VBUS. A typical application that includes UFP is a display monitor.
(3) DRP (Dual Role Port): Please note that DRP is divided into DRD (Dual Role Data)/DRP (Dual Role Power)
The port can be used as a DFP (host) or UFP (device). The power role of this type of port when connected determines its initial role. The source port assumes the data role of the DFP, while the receiving port assumes the data role of the UFP. However, by using the USB PD data role swapping feature, the data role of such ports can be changed dynamically. Typical applications that include DRD ports are laptops, tablets, and smartphones.
Three Power Flows (Power Role) of Type-C
(1) SINK: A sink port is a port that consumes VBUS power when connected. The sink port device is usually a power-consuming device. Common sink port applications include USB peripherals such as USB-powered lights or fans.
(2) SOURCE: A source port is a port that is powered by VBUS when connected. A common source port is a host or hub DFP. A typical source port application is a USB Type-C wall charger.
(3) Dual Role Power (DRP) port: A port that can be used as a sink port or a source port and can switch between these two states. When a DRP is initially used as a source port, the port assumes the data role of a DFP. Alternatively, when a DRP is initially used as a sink port, the port assumes the data role of a UFP. However, by using the USB PD power role swapping feature, the power role of a DRP port can be changed dynamically. For example, a laptop computer may include a DRP port that can receive power to charge the laptop battery and can also provide power to charge an external accessory. In addition, there are two special subtypes of DRP ports:
– Source devices, which are ports that can provide power but cannot function as a DFP. An example of this subtype is a USB Type-C and USB PD-compatible monitor that can receive data from a laptop DFP but cannot charge the laptop.
– Sink hosts, which are ports that can consume power but cannot function as a UFP. Examples include a hub’s DFP that can send data to an accessory while providing power to that accessory.