SLLSEQ8D October 2015 – May 2017 TUSB320HAI , TUSB320LAI
PRODUCTION DATA.
The USB Type-C ecosystem operates around a small form factor connector and cable that is flippable and reversible. Because of the nature of the connector, a scheme is required to determine the connector orientation. Additional schemes are required to determine when a USB port is attached and what the acting role of the USB port (DFP, UFP, DRP) is, as well as to communicate Type-C current capabilities. These schemes are implemented over the CC pins according to the USB Type-C pecification. The TUSB320 devices provide Configuration Channel (CC) logic for determining USB port attach and detach, role detection, cable orientation, and Type-C current mode. The TUSB320 devices also contains several features such as mode configuration and low standby current which make these devices ideal for source or sinks in USB2.0 applications.
Type-C specification defines several cables, plugs, and receptacles to be used to attach ports. The TUSB320 devices support all cables, receptacles, and plugs. The TUSB320 devices do not support any USB Type-C feature which requires USB power delivery communication over CC lines like e-marking or alternate mode.
Below is list of Type-C receptacles and plugs supported by the TUSB320 devices:
Below is a list of Type-C cables types supported by the TUSB320 devices:
The TUSB320 devices support legacy cable adapters as defined by the Type-C specification. The cable adapter must correspond to the mode configuration of a TUSB320 device.
Figure 3 displays the TUSB320 Legacy Adapter Implementation Circuit.
The TUSB320 devices support the attaching and detaching of a direct-connect device.
Additionally, the TUSB320 devices support audio adapters for audio accessory mode, including:
The TUSB320 devices can be configured as a downstream facing port (DFP), upstream facing port (UFP), or dual-role port (DRP) using the tri-level PORT pin. The PORT pin should be pulled high to VDD using a pullup resistance, low to GND or left as floated on the PCB to achieve the desired mode. This flexibility allows a TUSB320 device to be used in a variety of applications. A TUSB320 device samples the PORT pin after reset and maintains the desired mode until the TUSB320 device is reset again. The port role can also be selected through I2C registers. Table 1 lists the supported features in each mode:
PORT PIN | HIGH (DFP ONLY) |
LOW (UFP ONLY) |
NC (DRP) |
---|---|---|---|
SUPPORTED FEATURES | |||
Port attach and detach | Yes | Yes | Yes |
Cable orientation (through I2C) | Yes | Yes | Yes |
Current advertisement | Yes | - | Yes (DFP) |
Current detection | - | Yes | Yes (UFP) |
Accessory modes (audio and debug) | Yes | Yes | Yes |
Try.SRC | - | - | Yes |
Try.SNK | - | - | Yes |
Active cable detection | Yes | - | Yes (DFP) |
I2C / GPIO | Yes | Yes | Yes |
Legacy cables | Yes | Yes | Yes |
VBUS detection | - | Yes | Yes (UFP) |
The TUSB320 device can be configured as a DFP-only by pulling the PORT pin high through a resistance to VDD or by changing the MODE_SELECT register. In DFP-only mode, the TUSB320 device constantly presents Rps on both CC. In DFP-only mode, the TUSB320 device initially advertises default USB Type-C current. The Type-C current can be adjusted through I2C if the system requires to increase the amount advertised. The TUSB320 device adjusts the Rps to match the desired Type-C current advertisement. In GPIO mode, the TUSB320 device only advertises default Type-C current.
When configured as a DFP, the TUSB320 device can operate with older USB Type-C 1.0 devices except for a USB Type-C 1.0 DRP device. A USB Type-C 1.1 compliant DFP can not connect to a Type-C 1.0 DRP. Because the TUSB320 device is compliant to Type-C 1.1, the TUSB320 device can not operate with a USB Type-C 1.0 DRP device. This limitation is a result of a backwards compatibility problem between USB Type-C 1.1 DFP and a USB Type-C 1.0 DRP.
The TUSB320 device can be configured as a UFP only by pulling the PORT pin low to GND. In UFP mode, the TUSB320 device constantly presents pulldown resistors (Rd) on both CC pins. The TUSB320 device monitors the CC pins for the voltage level corresponding to the Type-C mode current advertisement by the connected DFP. The TUSB320 device debounces the CC pins and wait for VBUS detection before successfully attaching. As a UFP, the TUSB320 device detects and communicates the advertised current level of the DFP to the system through the OUT1 and OUT2 GPIOs (if in GPIO mode) or through the I2C CURRENT_MODE_DETECT register one time in the Attached.SNK state.
The TUSB320 device can be configured to operate as a DRP when the PORT pin is left floated on the PCB. In DRP mode, the TUSB320 device toggles between operating as a DFP and a UFP. When functioning as a DFP in DRP mode, the TUSB320 device complies with all operations as defined for a DFP according to the Type-C specification. When presenting as a UFP in DRP mode, the TUSB320 device operates as defined for a UFP according to the Type-C specification.
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.
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 USB2.0) or max of 900 mA (for USB3.1). If a higher level of current is available, the I2C registers can be written 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. If a DFP advertises 3 A, system designer must ensure that the VDD of the TUSB320 device is 3.5 V or greater. Table 2 lists the Type-C current advertisements in GPIO an I2C modes.
TYPE-C CURRENT | GPIO MODE (ADDR PIN IN NC) | I2C MODE (ADDR PIN H, L) | |||
---|---|---|---|---|---|
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 and read through I2C register | I2C register default is 500 or 900 mA (max) |
Medium - 1.5 A (max) | N/A | Advertisement selected through writing I2C register | |||
High - 3 A (max) |
The TUSB320 device supports audio and debug accessories in UFP, DFP mode and DRP mode. Audio and debug accessory support is provided through reading of I2C registers. Audio accessory is also supported through GPIO mode with INT_N/OUT3 pin (audio accessory is detected when INT_N/OUT3 pin is low).
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 adapter contains a receptacle and a plug. The plug acts as a DFP and supply VBUS when the plug detects a 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.
Debug is an additional state supported by USB Type-C. The specification does not define a specific user scenario for this state, but the specification is important because the end user could use debug accessory mode to enter a test state for production specific to the application. The TUBS320 device will detect a debug accessory if Rd or Rp is detected on both CC1 and CC2.
The TUSB320 device can be configured for I2C communication or GPIO outputs using the ADDR pin. The ADDR pin is a tri-level control pin. When the ADDR pin is left floating (NC), the TUSB320 device is in GPIO output mode. When the ADDR pin is pulled high or pulled low, the TUSB320 device is in I2C mode.
All outputs for the TUSB320 device are open drain configuration.
The OUT1 and OUT2 pins are used to output the Type-C current mode when in GPIO mode. Additionally, the OUT3 pin is used to communicate the audio accessory mode in GPIO mode. Table 3 lists the output pin settings. See the Pin Configuration and Functions section for more information.
OUT1 | OUT2 | ADVERTISEMENT |
---|---|---|
H | H | Default Current in Unattached State |
H | L | Default Current in Attached State |
L | H | Medium Current (1.5 A) in Attached State |
L | L | High Current (3.0 A) in Attached State |
When operating in I2C mode, the TUSB320 device uses the SCL and SDA lines for clock and data and the INT_N pin to communicate a change in I2C registers, or an interrupt, to the system. The INT_N pin is pulled low when the TUSB320 device updates the registers with new information. The INT_N pin is open drain. The INTERRUPT_STATUS register will be set when the INT_N pin is pulled low. To clear the INTERRUPT_STATUS register, the end user writes to I2C.
When operating in GPIO mode, the OUT3 pin is used in place of the INT_N pin to determine if an audio accessory is detected and attached. The OUT3 pin is pulled low when an audio accessory is detected.
NOTE
When using the 3.3 V supply for I2C, the end user must ensure that the VDD is 3 V and above. Otherwise the I2C can back power the device.
The TUSB320 device supports VBUS detection according to the Type-C specification. VBUS detection is used to determine the attachment and detachment of a UFP and to determine the entering and exiting of accessary modes. VBUS detection is also used to successfully resolve the role in DRP mode.
The system VBUS voltage must be routed through a 900-kΩ resistor to the VBUS_DET pin on the TUSB320 device if the PORT pin is configured as a DRP or a UFP. If the TUSB320 device is configured as a DFP and only ever used in DFP mode, the VBUS_DET pin can be left unconnected.
The TUSB320 device has four functional modes. Table 4 lists these modes:
MODES | GENERAL BEHAVIOR | PORT PIN | STATES(1) |
---|---|---|---|
Unattached | USB port unattached. ID, PORT operational. I2C on. CC pins configure according to PORT pin. | UFP | Unattached.SNK |
Unattached.Accessory | |||
AttachWait.Accessory | |||
AttachWait.SNK | |||
DRP | Toggle Unattached.SNK → Unattached.SRC | ||
AttachedWait.SRC or AttachedWait.SNK | |||
DFP | Unattached.SRC | ||
AttachWait.SRC | |||
Active | USB port attached. All GPIOs operational. I2C on. | UFP | Attached.SNK |
Audio accessory | |||
Debug accessory.SNK | |||
DRP | Attached.SNK | ||
Attached.SRC | |||
Audio accessory | |||
Debug accessory.SNK or Debug accessory.SRC | |||
DFP | Attached.SRC | ||
Audio accessory | |||
Debug accessory.SRC | |||
Dead battery | No operation. VDD not available. |
UFP/DRP/DFP | Default device state to UFP/SNK with Rd. |
Shutdown | VDD available. TUSB320LA EN_N pin high. TUSB320HA EN pin low. |
UFP/DRP/DFP | Default device state to UFP/SNK with Rd. |
Unattached mode is the primary mode of operation for the TUSB320 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 TUSB320 device is powered up, the part enters unattached mode until a successful attach has been determined. Initially, right after power up, the TUSB320 device comes up as an Unattached.SNK. The TUSB320 device checks the PORT pin and operates according to the mode configuration. The TUSB320 device toggles between the UFP and the DFP if configured as a DRP. In unattached mode, I2C can be used to change the mode configuration or port role if the board configuration of the PORT pin is not the desired mode. Writing to the I2C MODE_SELECT register can override the PORT pin in unattached mode. The PORT pin is only sampled at reset (EN_N high to low transition for the TUSB320LA device or the EN low to high transition for theTUSB320HA device), after I2C_SOFT_RESET, or power up. I2C must be used after reset to change the device mode configuration.
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 TUSB320 device communicates to the AP that the USB port is attached. This communication happens through the ID pin if TUSB320 is configured as a DFP or DRP connect as source. If TUSB320 is configured as a UFP or a DRP connected as a sink, the OUT1/OUT2 and INT_N/OUT3 pins are used. The TUSB320 device exits active mode under the following conditions:
During active mode, I2C be used to change the mode configuration following the sequence below. This same sequence is valid when TUSB320 is in unattached mode.
During dead battery mode, VDD is not available. CC pins always default to pulldown resistors in dead battery mode. Dead battery mode means:
NOTE
When VDD is off, the TUSB320 non-failsafe pins (VBUS_DET, ADDR, PORT, OUT[3:1] pins) could back-drive the TUSB320 device if not handled properly. When necessary to pull these pins up, TI recommendeds pulling up PORT, 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.
Shutdown mode for TUSB320LA device is defined as follows:
Shutdown mode for TUSB320HA device is defined as follows:
For further programmability, the TUSB320 device can be controlled using I2C. The TUSB320 device local I2C interface is available for reading/writing after TI2C_EN when the device is powered up. The SCL and SDA terminals are used for I2C clock and I2C data respectively. If I2C is the preferred method of control, the ADDR pin must be set accordingly.
TUSB320 I2C Target Address | ||||||||
---|---|---|---|---|---|---|---|---|
ADDR pin | Bit 7 (MSB) | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 (W/R) |
H | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 0/1 |
L | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0/1 |
The following procedure should be followed to write to TUSB320 I2C registers:
The following procedure should be followed to read the TUSB320 I2C registers:
The following procedure should be followed for setting a starting sub-address for I2C reads:
NOTE
If no sub-addressing is included for the read procedure, then the reads start at register offset 00h and continue byte-by-byte through the registers until the I2C master terminates the read operation. If a I2C address write occurred prior to the read, then the reads start at the sub-address specified by the address write.
ACCESS TAG | NAME | MEANING |
---|---|---|
R | Read | The field can be read by software. |
W | Write | The field can be written by software. |
S | Set | The field can be set by a write of one. Writes of zeros to the field have no effect. |
C | Clear | The field can be cleared by a write of one. Writes of zeros to the field have no effect. |
U | Update | Hardware can autonomously update this field. |
NA | No Access | Not accessible or not applicable. |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
DEVICE_ID | |||||||
R |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7:0 | DEVICE_ID | R | For the TUSB320 device these fields return a string of ASCII characters returning TUSB320 Addresses 0x07 - 0x00 = {0x00 0x54 0x55 0x53 0x42 0x33 0x32 0x30} |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
CURRENT_MODE_ADVERTISE | CURRENT_MODE_DETECT | ACCESSORY_CONNECTED | ACTIVE_CABLE_ DETECTION |
||||
RW | RU | RU | RU |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7:6 | CURRENT_MODE_ADVERTISE |
RW |
00 | These bits are programmed by the application to raise the current advertisement from default. 00 – Default (500 mA / 900 mA) initial value at startup 01 – Mid (1.5 A) 10 – High (3 A) 11 – Reserved |
5:4 | CURRENT_MODE_DETECT |
RU |
00 | These bits are set when a UFP determines the Type-C Current mode. 00 – Default (value at start up) 01 – Medium 10 – Audio Charged through accessory – 500 mA 11 – High |
3:1 | ACCESSORY_CONNECTED |
RU |
000 | These bits are read by the application to determine if an accessory was attached. 000 – No accessory attached (default) 001 – Reserved 010 – Reserved 011 – Reserved 100 – Audio accessory 101 – Audio charged thru accessory 110 – Debug accessory when the TUSB320 device is connected as a DFP. 111 – Debug accessory when the TUSB320 device is connected as a UFP. |
0 | ACTIVE_CABLE_DETECTION | RU | 0 | This flag indicates that an active cable has been plugged into the Type-C connector. When this field is set, an active cable is detected. |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
ATTACHED_STATE | CABLE_DIR | INTERRUPT_STATUS | — | DRP_DUTY_CYCLE | DISABLE_UFP_ ACCESSORY |
||
RU | RU | RCU | R | RW | RW |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
DEBOUNCE | MODE_SELECT | I2C_SOFT_RESET | SOURCE_PREF | DISABLE_TERM | |||
RW | RW | RSU | RW | RW |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7:6 | DEBOUNCE |
RW |
00 | The nominal amount of time the TUSB320 device debounces the voltages on the CC pins. 00 – 168 ms (default) 01 – 118 ms 10 – 134 ms 11 – 152 ms |
5:4 | MODE_SELECT |
RW |
00 | This register can be written to set the TUSB320 device mode operation. The ADDR pin must be set to I2C mode. If the default is maintained, the TUSB320 device operates according to the PORT pin levels and modes. 00 – Maintain mode according to PORT pin selection (default) 01 – UFP mode (unattached.SNK) 10 – DFP mode(unattached.SRC) 11 – DRP mode(start from unattached.SNK) |
3 | I2C_SOFT_RESET | RSU | 0 | This resets the digital logic. The bit is self-clearing. A write of 1 starts the reset. The following registers can be affected after setting this bit: CURRENT_MODE_DETECT ACTIVE_CABLE_DETECTION ACCESSORY_CONNECTED ATTACHED_STATE CABLE_DIR |
2:1 | SOURCE_PREF | RW | 00 | This field controls the TUSB320 behavior when configured as a DRP. 00 – Standard DRP (default) 01 – DRP will perform Try.SNK. 10 – Reserved. 11 – DRP will perform Try.SRC. |
0 | DISABLE_TERM | RW | 0 | This field will disable the termination on the CC pins and transition the CC state machine of the TUSB320 device to the Disable State. 0 – Termination enabled according to Port (Default) 1 – Termination disabled and state machine held in Disabled state. |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
— | DISABLE_RD_RP | — | |||||
R | RW | RW |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7:3 | Reserved | R | 00000 | Reserved |
2 | DISABLE_RD_RP | RW | 0 | When this field is set, Rd and Rp are disabled. 0 – Normal operation (default) 1 – Disable Rd and Rp |
1:0 | Reserved | RW | 00 | For TI internal use only. Do not change default value. |
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
REVISION | |||||||
R |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
7:0 | REVISION | R | 0x02 | Revision of TUSB320. Defaults to 0x02. |