The Type-C port mode is determined by the state of the PORT pin. When the PORT pin is pulled high, the

TUSB320 device is in DFP mode. The Type-C port mode can also be controlled by the MODE_SELECT register

through the I2C interface when the TUSB320 device is in the unattached state.

The VBUS_DET pin must be connected through a 900-kΩ resistor to VBUS on the Type-C that is connected. This

large resistor is required to protect the TUSB320 device from the largest VBUS voltage that is possible in present

day systems. This resistor along with internal pulldown keeps the voltage observed by the TUSB320 device in

the recommended range.

The USB2 specification requires the bulk capacitance on VBUS based on UFP or DFP. When operating the

TUSB320 device in a DFP mode, a bulk capacitance of at least 120 µF is required. In this particular case, a

150-µF capacitor was chosen.

8.2.2.3 Application Curves

Figure 8-10. Application Curve for DFP in I2C Mode

TUSB320, TUSB320I

SLLSEN9F – MAY 2015 – REVISED MARCH 2022

www.ti.com

24

Submit Document Feedback

Copyright © 2022 Texas Instruments Incorporated

Product Folder Links: TUSB320 TUSB320I