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TUSB320LAI, TUSB320HAI

www.ti.com

SLLSEQ8B – OCTOBER 2015 – REVISED SEPTEMBER 2016

Product Folder Links: TUSB320LAI TUSB320HAI

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Copyright © 2015–2016, Texas Instruments Incorporated

The TUSB320 supports two optional Type-C DRP features called Try.SRC and Try.SNK. Products supporting

dual-role functionality may have a requirement to be a source (DFP) or a sink (UFP) when connected to another

dual-role capable product. For example, a dual-role capable notebook can be a source when connected to a

tablet, or a cell phone can be a sink when connected to a notebook or tablet. When standard DRP products

(products which don’t support either Try.SRC or Try.SNK) are connected together, the role (UFP or DFP)

outcome is not predetermined. These two optional DRP features provide a means for dual-role capable products

to connect to another dual-role capable product in the role desired. Try.SRC and Try.SNK are only available

when TUSB320 is configured in I2C mode. When operating in GPIO mode, the TUSB320 will always operate as

a standard DRP.

The Try.SRC feature of the TUSB320 device provides a means for a DRP product to connect as a DFP when

connected to another DRP product that doesn’t implement Try.SRC. When two products which implement

Try.SRC are connected together, the role outcome of either UFP or DFP is the same as a standard DRP.

Try.SRC is enabled by changing I2C register SOURCE_PREF to 2’b11. Once this register is changed to 2’b11,

the TUSB320 will always attempt to connect as a DFP when attached to another DRP capable device.

The Try.SNK feature of the TUSB320 device provides a method for a DRP product to connect as a UFP when

connected to another DRP product that doesn’t implement Try.SNK. When two products which implement

Try.SNK are connected together, the role outcome of either UFP or DFP is the same as a standard DRP.

Try.SNK is enabled by changing I2C register SOURCE_PREF to 2’b01. Once this register is changed to 2’b01,

the TUSB320 will always attempt to connect as a UFP when attached to another DRP capable device.

7.2.2 Type-C Current Mode

When a valid cable detection and attach have been completed, the DFP has the option to advertise the level of

Type-C current a UFP can sink. The default current advertisement for the TUSB320 device is max of 500 mA (for

to provide medium current at 1.5 A or high current at 3 A. When the CURRENT_MODE_ADVERTISE register

has been written to advertise higher than default current, the DFP adjusts the Rps for the specified current level.

TYPE-C CURRENT

GPIO MODE (ADDR PIN IN NC)

UFP (PORT PIN L)

DFP (PORT PIN H)

UFP

DFP

Default

max of 500

mA (USB2.0)

max of 900

mA (USB3.1)

Current mode detected

and output through OUT1

/ OUT2

Only advertisement

Current mode detected

register

or 900 mA (max)

Medium - 1.5 A (max)

N/A

Advertisement selected

register

High - 3 A (max)

7.2.3 Accessory Support

The TUSB320 device supports audio and debug accessories in UFP, DFP mode and DRP mode. Audio and

GPIO mode with INT_N/OUT3 pin (audio accessory is detected when INT_N/OUT3 pin is low).

7.2.3.1 Audio Accessory

Audio accessory mode is supported through two types of adapters. First, the passive audio adapter can be used

to convert the Type-C connector into an audio port. To effectively detect the passive audio adapter, the TUSB320

device must detect a resistance < Ra on both of the CC pins.

Secondly, a charge through audio adapter can be used. The primary difference between a passive and charge

through adapter is that the charge through adapter supplies 500 mA of current over VBUS. The charge through

connection.

When the TUSB320 device is configured in GPIO mode, OUT3 pin determines if an audio accessory is

connected. When an audio accessory is detected, the OUT3 pin is pulled low.