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TPS65981
www.ti.com
SLVSDC2B –FEBRUARY 2016–REVISED AUGUST 2016
Product Folder Links: TPS65981
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Pin Functions (continued)
PIN CATEGORY I/O TYPE POR STATE DESCRIPTION
NAME NO.
DEBUG_CTL1 45 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 16. At power-up, pin state is sensed
to determine bit 4 of the I2C address.
DEBUG_CTL2 44 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 17. At power-up, pin state is sensed
to determine bit 5 of the I2C address.
DEBUG1 2 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 15. Ground pin with a 1-MΩresistor
when unused in the application.
GPIO0 41 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 0. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
GPIO2 25 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 2. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
GPIO3 19 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 3. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
GPIO4 26 Digital Core I/O
and Control Digital I/O Hi-Z
General-purpose digital I/O 4. Configured as a hot-plug detect
(HPD) transistor, HPD receiver, or both when DisplayPort mode is
supported. Ground pin with a 1-MΩresistor when unused in the
application.
GPIO5 23 Digital Core I/O
and Control Digital I/O Hi-Z
General-purpose digital I/O 5. Can be configured as a HPD
receiver when DisplayPort mode is supported. Must be tied high
or low through a 1-kΩpull-up or pull-down resistor when used as
a configuration input. Ground pin with a 1-MΩresistor when
unused in the application.
GPIO6 20 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 6. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
GPIO7 38 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 7. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
GPIO8 1 Digital Core I/O
and Control Digital I/O Hi-Z General-purpose digital I/O 8. Float pin if it is configured as a
push-pull output in the application. Ground pin with a 1-MΩ
resistor when unused in the application.
HV_GATE1 31 External HV FET
Control and Sense Analog Output Short to
SENSEP External NFET gate control for high voltage power path. Float pin
when unused.
HV_GATE2 32 External HV FET
Control and Sense Analog Output Short to
VBUS External NFET gate control for high voltage power path. Float pin
when unused.
I2C_IRQZ 43 Digital Core I/O
and Control Digital Output Hi-Z I2C port interrupt. Active low. Implement externally as an open-
drain with a pull-up resistance. Float pin when unused.
I2C_SCL 47 Digital Core I/O
and Control Digital I/O Digital Input I2C port serial clock. Open-drain output. Tie pin to LDO_3V3 or
VDDIO (depending on configuration) through a 10-kΩresistor
when used or unused.
I2C_SDA 46 Digital Core I/O
and Control Digital I/O Digital Input I2C port serial data. Open-drain output. Tie pin to LDO_3V3 or
VDDIO (depending on configuration) through a 10-kΩresistor
when used or unused.
LDO_1V8A 56 Low Current Power N/A Output of the 1.8-V LDO for core analog circuits. Bypass with
capacitance CLDO_1V8A to GND.
LDO_1V8D 40 Low Current Power N/A Output of the 1.8-V LDO for core digital circuits. Bypass with
capacitance CLDO_1V8D to GND.
LDO_3V3 51 Low Current Power N/A Output of the VBUS to 3.3-V LDO or connected to VIN_3V3 by a
switch. Main internal supply rail. Used to power external flash
memory. Bypass with capacitance CLDO_3V3 to GND.
LDO_BMC 48 Low Current Power N/A Output of the USB-PD BMC transceiver output level LDO. Bypass
with capacitance CLDO_BMC to GND.
MRESET 24 Digital Core I/O
and Control Digital I/O Hi-Z
General-purpose digital I/O 11. Forces RESETZ to assert. By
default, this pin asserts RESETZ when pulled high. The pin can
be programmed to assert RESETZ when pulled low. Ground pin
with a 1-MΩresistor when unused in the application.
PP_5V0 27 High Current Power N/A 5-V supply for VBUS. Bypass with capacitance CPP_5V0 to
GND. Tie pin to GND when unused
28
PP_CABLE 14 High Current Power N/A 5-V supply for C_CC pins. Bypass with capacitance CPP_CABLE
to GND when not tied to PP_5V0. Tie pin to PP_5V0 when
unused.