Table 6-4. USB Type-C States According to TUSB322I Functional Modes (continued)

MODES

GENERAL BEHAVIOR

MODE

STATES(1)

Shutdown

No operation.

VDD available and EN_N pin high

DRP

Default device state to UFP/SNK with Rd.

(1)

Required; not in sequential order.

6.4.1 Unattached Mode

Unattached mode is the primary mode of operation for the TUSB322I device, because a USB port can be

unattached for a lengthy period of time. In unattached mode, VDD is available, and all IOs and I2C are

operational. After the TUSB322I device is powered up, the part enters unattached mode until a successful attach

has been determined. Initially, right after power up, the TUSB322I device comes up as an Unattached.SNK. The

TUSB322I device toggles between the UFP and the DFP if configured as a DRP.

6.4.2 Active Mode

Active mode is defined as the port being attached. In active mode, all GPIOs are operational, and I2C is read /

write (R/W). When in active mode, the TUSB322I device communicates to the AP that the USB port is attached.

This communication happens through the ID pin if TUSB322I is configured as a DFP or DRP connect as source.

If TUSB322I is configured as a UFP or a DRP connected as a sink, the OUT1/OUT2 and INT_N/OUT3 pins are

used. The TUSB322I device exits active mode under the following conditions:

• Cable unplug

• VBUS removal if attached as a UFP

• Dead battery; system battery or supply is removed

• EN_N is floated or pulled high.

6.4.3 Shutdown Mode

Shutdown mode for TUSB322I is defined as follows:

• Supply voltage available and EN_N pin is high or floating.

• EN_N pin has internal pullup resistor

• The TUSB322I device is off, but still maintains the Rd on the CC pins.

6.4.4 Dead Battery Mode

During dead battery mode, VDD is not available. CC pins always default to pulldown resistors in dead battery

mode. Dead battery mode means:

• TUSB322I in UFP with 5.1 kΩ ± 20% Rd; cable connected and providing charge

• TUSB322I in UFP with 5.1 kΩ ± 20% Rd; nothing connected (application could be off or have a discharged

battery)

Note

When VDD is off, the TUSB322I non-failsafe pins (DIR, VBUS_DET, ADDR, OUT[3:1] pins) could

back-drive the TUSB322I device if not handled properly. When necessary to pull these pins up, TI

recommends pulling up DIR, ADDR, and INT_N/OUT3 to the device’s VDD supply. The VBUS_DET

must be pulled up to VBUS through a 900-kΩ resistor.

TUSB322I

SLLSEO5D – OCTOBER 2015 – REVISED MARCH 2021

www.ti.com

14

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