UM2191
USB
Type-C and Power Delivery
DocID030479 Rev 2
11/55
1.6
CC pins: port termination characteristics
The configuration channel (CC) pins are used in the discovery, configuration and
management of connection across a USB Type-
C™ cable, as well as a communication
channel for the PHY layer of the USB Power Delivery.
There are two CC pins in each receptacle, but only one is connected through the cable to
establish communication. The other pin can be re-assigned as the V
CONN
pin for powering
electronics in the USB Type-
C™ plug of electronically-marked cables.
Specific Rd and Rp resistor values connected to CC pins allow single role or dual role
system configuration. The attachment and orientation detection operations are carried out
through CC lines through these resistors:
a source must assert Rp pull-up resistors on both CC1 and CC2
a sink must assert Rd pull-down resistors on both CC pins
a dual role power (DRP) is equipped with both Rp pull-up resistors and Rd pull-down
resistors on its CC pins and is able to dynamically assert the appropriate resistors
when the role is fixed by the application according to the operated power role.
A full-featured USB Type-C cable must assert Ra pull-down resistors on the V
CONN
pin.
The following table provides the values to be used for Rp or current source.
Table 2: Source CC termination (Rp) requirements
Source
Current Capability
Current Source
to 1.7 V - 5.5 V
Rp pull-up
to 3.3 V ±5%
Rp pull-up
to 4.75 V - 5.5 V
Default USB power
80 µA ±20%
36
kΩ ±20%
56
kΩ ±20%
1.5 A at 5 V
180 µA ±8%
12
kΩ ±5%
22
kΩ ±5%
3.0 A at 5 V
330 µA ±8%
4.7
kΩ ±5%
10
kΩ ±5%
Rp resistors connected to both CC pins may be pulled-up to 3.3 V or 5 V. The resistor
value is chosen on the basis the device port supplying capability. Moreover, if the source
role is operated, the Rp resistors can be replaced by current sources.
The following table provides the values to be used for Rd or Sink CC termination.
Table 3: Sink CC termination (Rd) requirements
Rd setting
Nominal Value
Max Voltage on pin
Power Capability detection
±20% voltage clamp
1.1 V
1.32 V
No
±20% resistor to GND
5.1
kΩ
2.18 V
No
±10% resistor to GND
5.1
kΩ
2.04 V
Yes
Rd resistors may be implemented in multiple ways.
1.7
Power options
Regarding power exchange, every platform equipped with a Type-
C™ connector but
without power delivery must be able to support 5 V with one of the specific current
capabilities. When power delivery is supported and the design is specifically optimized for
managing high power loads, the same platform may support up to 20 V at 5 A (100 W).