FUSB307B
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5
Pin Descriptions
Table 2. PIN DESCRIPTION
Name Type Description
USB TYPE−C CONNECTOR INTERFACE
CC1 I/O
Type−C connector Configuration Channel (CC) pins. Initially used to determine
when an attach has occurred and what the orientation of the insertion is. Function
ality after attach depends on mode of operation detected.
Operating as a host:
− Sets the allowable charging current for VBUS to be sensed by the attached
device
− Used to communicate with devices using USB BMC Power Delivery
− Used to detect when a detach has occurred
Operating as a device:
− Indicates what the allowable sink current is from the attached host
− Used to communicate with devices using USB BMC Power Delivery
CC2 I/O
GND Ground Ground
VBUS Power VBUS supply pin for attach and detach detection when operating as an upstream
facing port (Device)
POWER INTERFACE
VDD Power Input supply voltage
LDO LDO Output 3.3 V LDO Output
VCONN Power Switch Regulated input to be switched to correct CC pin as VCONN to power USB3.1
fully featured cables, powered accessories or dongles bridging Type C to other
video or audio connectors
SIGNAL INTERFACE
SCL1/SDA2 (Note 1) Open−Drain I/O I
2
C serial clock/data signal to be connected to the I
2
C master
SDA1/SCL2 (Note 1) Open−Drain I/O I
2
C serial clock/data signal to be connected to the I
2
C master
INT_N Open−Drain Output Active LOW open drain interrupt output used to prompt the processor to read the
I
2
C register bits
ORIENT/I2C_
ADDR
(Note 1)
3−State CMOS Output Selects I
2
C Address on Power up and then becomes a General Purpose CMOS
Output
DBG_N Open−Drain I/O Debug Accessory Detection Open−Drain Output
GPIO2 3−State CMOS I/O General Purpose I/O 2
GPIO1 3−State CMOS I/O General Purpose I/O 1
VBUS SOURCE AND SINK INTERFACE
SNK CMOS Output Controls external VBUS Sink Load Switch on/off (Active High)
SRC CMOS Output Controls external VBUS Source Load Switch on/off (Active High)
1. A different I2C address is used depending on which SDA and SCL are used and the state of ORIENT/I2C_ADDR at power up.
Power Up, Initialization and Reset
When power is first applied to VDD or VBUS, the
FUSB307B goes through its POR sequence to load up all the
default values in the register map, read all the fuses so that
the trimmed values are available when VDD or VBUS is in
its valid range. A software reset can be executed by writing
SW_RES to 1 in RESET Register. This executes a full reset
of the FUSB307B similar to POR where all the I2C registers
go to their default state.
When powered down, the FUSB307B is configured as a
UFP with CC1 and CC2 have their respective Rd
pull−downs enabled such that a SOURCE can detect this as
a UFP and turn on VBUS.
For the FUSB307B device, power may become available
from VBUS when VDD is not present. This state is still
considered “Dead Battery” until VDD is present. During
Dead Battery, the FUSB307B will continue presenting Rd.
Once VDD is available, the TCPM can start the DRP
toggle by setting COMMAND.LOOK4CON on the
FUSB307B device.
