2.3.11

SCLK

The serial clock signal from the STUSB1702 drives the SPI/MSP interface of the MCU and the clock data on the

MISO and MOSI pins.

2.3.12

A_B_SIDE

This output pin provides cable orientation. It is used to establish USB SuperSpeed signal routing. The cable

orientation is also provided by an internal I²C register. This signal is not required in the case of USB 2.0 support.

Table 4. USB data MUX select

Value

CC pin position

HiZ

CC1 pin is attached to CC line

0

CC2 pin is attached to CC line

2.3.13

VBUS_SENSE

This input pin is used to sense VBUS presence, monitor VBUS voltage and discharge VBUS on USB Type-C

receptacle side.

2.3.14

VBUS_EN_SRC

In source power role, this pin allows the outgoing VBUS power to be enabled when the connection to a sink is

established and VBUS is in a valid operating range. The open drain output allows a PMOS transistor to be directly

driven. The logic value of the pin is also advertised in a dedicated I²C register bit.

2.3.15

VREG_1V2

This pin is used only for external decoupling of 1.2 V internal regulator. The recommended decoupling capacitor

is: 1 µF typ. (0.5 µF min.; 10 µF max.).

2.3.16

VSYS

This is the low power supply of the system, if there is any. It can be connected directly to a system power supply

delivering 3.3 V or 5 V. It is recommended to connect this pin to ground when it is not used.

2.3.17

VREG_2V7

This pin is used for external decoupling of the 2.7 V internal regulator. The recommended decoupling capacitor is:

1 µF typ. (0.5 µF min., 10 µF max.).

2.3.18

VDD

This is the power supply from the USB power line for applications powered by VBUS.

In source power role, this pin can be used to sense the voltage level of the main power supply providing the VBUS.

It allows UVLO and OVLO thresholds to be considered independently on the VDD pin as additional conditions to

enable the VBUS power path through the VBUS_EN_SRC pin (see Section 3.3.3 VBUS power path assertion).

When the UVLO threshold detection is enabled, the VDD pin must be connected to the main power supply to

establish the connection and to assert the VBUS power path.

STUSB1702

Pin description

DS12664 - Rev 1

page 6/38