SLLSET2 August 2017 TUSB8042

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (Continued)
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1Absolute Maximum Ratings
    2. 7.2ESD Ratings
    3. 7.3Recommended Operating Conditions
    4. 7.4Thermal Information
    5. 7.5Electrical Characteristics, 3.3-V I/O
    6. 7.6Timing Requirements, Power-Up
    7. 7.7Hub Input Supply Current
  8. Detailed Description
    1. 8.1Overview
    2. 8.2Functional Block Diagram
    3. 8.3Feature Description
      1. 8.3.1Battery Charging Features
      2. 8.3.2 USB Power Management
      3. 8.3.3One Time Programmable (OTP) Configuration
      4. 8.3.4Clock Generation
      5. 8.3.5Crystal Requirements
      6. 8.3.6Input Clock Requirements
      7. 8.3.7Power-Up and Reset
    4. 8.4Device Functional Modes
      1. 8.4.1External Configuration Interface
      2. 8.4.2I2C EEPROM Operation
      3. 8.4.3Port Configuration
      4. 8.4.4SMBus Slave Operation
    5. 8.5Register Maps
      1. 8.5.1 Configuration Registers
      2. 8.5.2 ROM Signature Register
      3. 8.5.3 Vendor ID LSB Register
      4. 8.5.4 Vendor ID MSB Register
      5. 8.5.5 Product ID LSB Register
      6. 8.5.6 Product ID MSB Register
      7. 8.5.7 Device Configuration Register
      8. 8.5.8 Battery Charging Support Register
      9. 8.5.9 Device Removable Configuration Register
      10. 8.5.10Port Used Configuration Register
      11. 8.5.11Device Configuration Register 2
      12. 8.5.12USB 2.0 Port Polarity Control Register
      13. 8.5.13UUID Registers
      14. 8.5.14Language ID LSB Register
      15. 8.5.15Language ID MSB Register
      16. 8.5.16Serial Number String Length Register
      17. 8.5.17Manufacturer String Length Register
      18. 8.5.18Product String Length Register
      19. 8.5.19Device Configuration Register 3
      20. 8.5.20USB 2.0 Only Port Register
      21. 8.5.21Serial Number String Registers
      22. 8.5.22Manufacturer String Registers
      23. 8.5.23Product String Registers
      24. 8.5.24Additional Feature Configuration Register
      25. 8.5.25SMBus Device Status and Command Register
  9. Applications and Implementation
    1. 9.1Application Information
    2. 9.2Typical Application
      1. 9.2.1Discrete USB Hub Product
        1. 9.2.1.1Design Requirements
        2. 9.2.1.2Detailed Design Procedure
          1. 9.2.1.2.1Upstream Port Implementation
          2. 9.2.1.2.2Downstream Port 1 Implementation
          3. 9.2.1.2.3Downstream Port 2 Implementation
          4. 9.2.1.2.4Downstream Port 3 Implementation
          5. 9.2.1.2.5Downstream Port 4 Implementation
          6. 9.2.1.2.6VBUS Power Switch Implementation
          7. 9.2.1.2.7Clock, Reset, and Misc
          8. 9.2.1.2.8TUSB8042 Power Implementation
        3. 9.2.1.3Application Curves
  10. 10Power Supply Recommendations
    1. 10.1TUSB8042 Power Supply
    2. 10.2Downstream Port Power
    3. 10.3Ground
  11. 11Layout
    1. 11.1Layout Guidelines
      1. 11.1.1Placement
      2. 11.1.2Package Specific
      3. 11.1.3Differential Pairs
    2. 11.2Layout Examples
      1. 11.2.1Upstream Port
      2. 11.2.2Downstream Port
  12. 12Device and Documentation Support
    1. 12.1Receiving Notification of Documentation Updates
    2. 12.2Community Resources
    3. 12.3Trademarks
    4. 12.4Electrostatic Discharge Caution
    5. 12.5Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Detailed Description

Overview

The TUSB8042 is a four-port USB 3.1 Gen1 compliant hub. It provides simultaneous SuperSpeed USB and high-speed/full-speed connections on the upstream port and provides SuperSpeed USB, high-speed, full-speed, or low-speed connections on the downstream ports. When the upstream port is connected to an electrical environment that only supports high-speed or full-speed/low-speed connections, SuperSpeed USB connectivity is disabled on the downstream ports. When the upstream port is connected to an electrical environment that only supports full-speed/low-speed connections, SuperSpeed USB and high-speed connectivity are disabled on the downstream ports.

Functional Block Diagram

TUSB8042 fbd_8042_sllet2.gif

Feature Description

Battery Charging Features

The TUSB8042 provides support for USB Battery Charging (BC1.2) and custom charging. Battery charging support may be enabled on a per port basis through the REG_6h(batEn[3:0]).

USB Battery charging support includes both Charging Downstream Port (CDP) and Dedicated Charging Port (DCP) modes. The DCP mode is compliant with the Chinese Telecommunications Industry Standard YD/T 1591-2009. CDP is enabled when the upstream port has detected valid VBUS, configured, and host sets port power. When the upstream port is not connected and battery charging support is enabled, the TUSB8042 will enable DCP mode.

In addition to USB Battery charging (BC1.2), the TUSB8042 supports custom charging indications: Divider Charging (ACP3, ACP2, ACP1 modes), and Galaxy compatible charging. These custom charging modes are only supported when upstream port is unconnected and AUTOMODE is enabled. When in AUTOMODE and upstream port is disconnected, the port will automatically transition from ACP mode to the DCP mode depending on the portable device connected. The divided mode places a fixed DC voltage on the ports DP and DM signals which allows some devices to identify the capabilities of the charger. The default divider mode indicates support for up to 10W (ACP3). The divider mode can be configured to report a lower-current setting (up to 5 W) through REG_0Ah (HiCurAcpModeEn).

When the upstream port is not connected and battery charging support is enabled for a port, the TUSB8042 drives the port power enable active. If AUTOMODE is disabled, then DCP mode is used. If AUTOMODE is enabled and FullAutoEn bit is cleared (Reg_25h Bit 0), then TUSB8042 will start with highest enabled divider current mode (ACPx). The TUSB8042 will remain in highest current mode as long as a pull-up is not detected on DP pin. If an pull-up is detected on DP pin, then TUSB8042 will drive the port power enable inactive and switch to Galaxy mode, if enabled, or to DCP mode if Galaxy mode is disabled. The TUSB8042 will again drive the port power enable active. The TUSB8042 will remain in Galaxy mode as long as no pull-up is detected on DP pin. If an pull-up is detected on DP pin, then TUSB8042 will drive the port power enable inactive and transition to DCP mode. The TUSB8042 will again drive the port power enable active. In DCP mode, the TUSB8042 will look for a pull-up detected on DP pin or RxVdat. If a pull-up or RxVdat is detected on DP, the TUSB8042 will remain in DCP mode. If no pull-up or RxVdat is detected on DP pin after 2 seconds, the TUSB8042 will drive the port power enable inactive and transition back to ACPx mode. This sequence will repeat until upstream port is connected.

When Automatic mode is enabled and full automatic mode (FullAutoEn Reg_25h bit 0) is enabled, TUSB8042 will perform same sequence described in previous paragraph with the addition of attempting all supported ACPx modes before sequencing to Galaxy Mode (if enabled) or DCP mode.

The supported battery charging modes when TUSB8042 configured for SMBus or external EEPROM is detailed in Battery Charging Modes with SMBus/EEPROM Table.

The supported battery charging modes when TUSB8042 configured for I2C but without an external EEPROM is determined by the sampled state of the pins. These modes are detailed in Battery Charging Modes without EEPROM Table.

Table 2. TUSB8042 Battery Charging Modes with SMBus or I2C EEPROM

batEn[n] Reg_06h Bits 3:0Upstream VBUSHiCurAcpMode En Reg_0Ah Bit 4autoModeEnz Reg_0Ah Bit 1FullAutoEn Reg_25h Bit 0Galaxy_Enz Reg_25h Bit 1Battery Charging Mode Port x
(x = n + 1)
0Don’t CareDon't CareDon’t CareDon't CareDon't CareNo Charging support
1> 4VDon't CareDon't CareDon't CareDon't CareCDP
1< 4VDon't Care1Don't CareDon't CareDCP
1< 4V0011AUTOMODE enabled. Sequences through all ACPx modes and DCP with the exception of ACP3
Alternate ACP2, ACP1, DCP
1< 4V1011AUTOMODE enabled. Sequences through all ACPx modes and DCP.
Alternate ACP3, ACP2, ACP1, DCP
1< 4 V0001AUTOMODE enabled. Sequences between ACP2 and DCP.
Alternate ACP2, DCP
1< 4V1001AUTOMODE enabled. Sequences between ACP3 and DCP.
Alternate ACP3, DCP
1< 4V0010AUTOMODE enabled with Galaxy compatible charging support.
Alternate ACP2, ACP1, Galaxy, DCP.
1< 4V1010AUTOMODE enabled with Galaxy compatible charging support.
Alternate ACP3, ACP2, ACP1, Galaxy, DCP
1< 4V0000AUTOMODE enabled with Galaxy compatible charging support.
Alternate ACP2, Galaxy, DCP
1< 4V1000AUTOMODE enabled with Galaxy compatible charging support.
Alternate ACP3, Galaxy, DCP

Table 3. TUSB8042 Battery Charging Modes without EEPROM

BATEN[3:0] pinsUpstream VBUSAUTOENz pinFULLAUTOz pinBattery Charging Mode Port x
(x = n + 1)
0Don’t CareDon’t CareDon't CareNo Charging support
1> 4VDon't CareDon't CareCDP
1< 4V10DCP
1< 4V00AUTOMODE enabled with Galaxy compatible charging support. Sequences through all ACPx modes.
Alternate ACP3, ACP2, ACP1, Galaxy, DCP.
1< 4V01AUTOMODE enabled with Galaxy compatible charging support.
Alternate ACP3, Galaxy, DCP
1< 4V11AUTOMODE enabled. Sequences through all ACPx modes.
Alternate ACP3, ACP2, ACP1, DCP.

USB Power Management

The TUSB8042 can be configured for power switched applications using either per-port (Full power managed) or ganged power-enable controls and over-current status inputs. When battery charge is enabled, the TUSB8042 will always function in full power managed.

Power switch support is enabled by REG_5h (fullPwrMgmtz) and the per-port or ganged mode is configured by REG_5h(ganged).

The TUSB8042 supports both active high and active low power-enable controls. The PWRCTL[4:1] polarity is configured by REG_Ah(pwrctlPol).

One Time Programmable (OTP) Configuration

The TUSB8042 allows device configuration through one time programmable non-volatile memory (OTP). The programming of the OTP is supported using vendor-defined USB device requests. For details using the OTP features please contact your TI representative.

Table 4 provides a list features which may be configured using the OTP.

Table 4. OTP Configurable Features

CONFIGURATION REGISTER OFFSETBIT FIELDDESCRIPTION
REG_01h[7:0]Vendor ID LSB
REG_02h[7:0]Vendor ID MSB
REG_03h[7:0]Product ID LSB
REG_04h[7:0]Product ID MSB
REG_07h[0]Port removable configuration for downstream ports 1. OTP configuration is inverse of rmbl[3:0], i.e. 1 = not removable, 0 = removable.
REG_07h[1]Port removable configuration for downstream ports 2. OTP configuration is inverse of rmbl[3:0], i.e. 1 = not removable, 0 = removable.
REG_07h[2]Port removable configuration for downstream ports 3. OTP configuration is inverse of rmbl[3:0], i.e. 1 = not removable, 0 = removable.
REG_07h[3]Port removable configuration for downstream ports 4. OTP configuration is inverse of rmbl[3:0], i.e. 1 = not removable, 0 = removable.
REG_08h[3:0]Port used Configured register.
REG_0Ah[3]Enable Device Attach Detection..
REG_0Ah[4]High-current divider mode enable.
REG_0Bh[0]USB 2.0 port polarity configuration for downstream ports 1.
REG_0Bh[1]USB 2.0 port polarity configuration for downstream ports 2.
REG_0Bh[2]USB 2.0 port polarity configuration for downstream ports 3.
REG_0Bh[3]USB 2.0 port polarity configuration for downstream ports 4.
REG_25h[4:0]Device Configuration Register 3
REG_26h[3:0]USB2.0 Only Port Register
REG_F0h[3:1]USB power switch power-on delay.

Clock Generation

The TUSB8042 accepts a crystal input to drive an internal oscillator or an external clock source. If a clock is provided to XI instead of a crystal, XO is left open. Otherwise, if a crystal is used, the connection needs to follow the guidelines below. Since XI and XO are coupled to other leads and supplies on the PCB, it is important to keep them as short as possible and away from any switching leads. It is also recommended to minimize the capacitance between XI and XO. This can be accomplished by shielding C1 and C2 with the clean ground lines.

TUSB8042 clock_sllset2.gif Figure 2. TUSB8042 Clock

Crystal Requirements

The crystal must be fundamental mode with load capacitance of 12 pF - 24 pF and frequency stability rating of ±100 PPM or better. To ensure proper startup oscillation condition, a maximum crystal equivalent series resistance (ESR) of 50 Ω is recommended. A parallel load capacitor should be used if a crystal source is used. The exact load capacitance value used depends on the crystal vendor. Refer to application note Selection and Specification for Crystals for Texas Instruments USB2.0 devices (SLLA122) for details on how to determine the load capacitance value.

Input Clock Requirements

When using an external clock source such as an oscillator, the reference clock should have a ±100 PPM or better frequency stability and have less than 50-ps absolute peak to peak jitter or less than 25-ps peak to peak jitter after applying the USB 3.1 jitter transfer function. XI should be tied to the 1.8-V clock source and XO should be left floating.

Power-Up and Reset

The TUSB8042 does not have specific power sequencing requirements with respect to the core power (VDD) or I/O and analog power (VDD33) as long as GRSTz is held in an asserted state while supplies ramp. The core power (VDD) or I/O power (VDD33) may be powered up for an indefinite period of time while the other is not powered up if all of these constraints are met:

  • All maximum ratings and recommended operating conditions are observed.
  • All warnings about exposure to maximum rated and recommended conditions are observed, particularly junction temperature. These apply to power transitions as well as normal operation.
  • Bus contention while VDD33 is powered up must be limited to 100 hours over the projected life-time of the device.
  • Bus contention while VDD33 is powered down may violate the absolute maximum ratings.

A supply bus is powered up when the voltage is within the recommended operating range. It is powered down when it is below that range, either stable or in transition.

A minimum reset duration of 3 ms is required. This is defined as the time when the power supplies are in the recommended operating range to the de-assertion of GRSTz. This can be generated using programmable-delay supervisory device or using an RC circuit. When a RC circuit is used, the external capacitor size chosen must be large enough to meet the 3ms minimum duration requirement. The R of the RC circuit is the internal RPU.

Device Functional Modes

External Configuration Interface

The TUSB8042 supports a serial interface for configuration register access. The device may be configured by an attached I2C EEPROM or accessed as a slave by an external SMBus master. The external interface is enabled when both the SCL/SMBCLK and SDA/SMBDAT pins are pulled up to 3.3 V at the de-assertion of reset. The mode, I2C master or SMBus slave, is determined by the state of SMBUSz/SS_SUSPEND pin at reset.

I2C EEPROM Operation

The TUSB8042 supports a single-master, fast mode (400KHz) connection to a dedicated I2C EEPROM when the I2C interface mode is enabled. In I2C mode, the TUSB8042 reads the contents of the EEPROM at bus address 1010000b using 7-bit addressing starting at address 0. The TUSB8042 will read the entire EEPROM contents using a single burst read transaction. The burst read transaction will end when the address reaches FFh.

If the value of the EEPROM contents at address byte 00h equals 55h, the TUSB8042 loads the configuration registers according to the EEPROM map. If the first byte is not 55h, the TUSB8042 exits the I2C mode and continues execution with the default values in the configuration registers. The hub will not connect on the upstream port until the configuration is completed.

NOTE

The bytes located above offset Ah are optional. The requirement for data in those addresses is dependent on the options configured in the Device Configuration, and Device Configuration 2 registers.

The minimum size I2C EEPROM required is 2Kbit.

For details on I2C operation refer to the UM10204 I2C-bus Specification and User Manual.

Port Configuration

The TUSB8042 port configurations can be selected by registers or efuse. The Port Used Configuration register (USED[3:0]) define how many ports can possibly be reported by the hub. The device removable configuration register (RMBL[3:0]) define if the ports that are reported as used have permanently connected devices or not. The USB 2.0 Only Port register (USB2_ONLY[3:0]) define whether or a used port is reported as part of the USB 2.0 hub or both the USB2.0 and USB3.1 hubs. The USB2_ONLY field will enable the USB2.0 port even if the corresponding USED bit is low. The table below shows examples of the possible combinations.

Table 5. TUSB8042 Downstream Port Configuration Examples

USED[3:0]RMBL[3:0]USB2_ONLY
[3:0]
Reported Port ConfigurationPhysical to Logical Port mapping
1111111100004 Port USB3.1 Hub
4 Port USB2.0 Hub

Physical1 => Logical Port1 for USB3.1 and USB2.0.


Physical2 => Logical Port2 for USB3.1 and USB2.0.


Physical3 => Logical Port3 for USB3.1 and USB2.0.


Physical4 => Logical Port4 for USB3.1 and USB2.0.

1110111100003 Port USB3.1 Hub
Port USB2.0 Hub

Physical1 Not used.


Physical2 => Logical Port1 for USB3.1 and USB2.0.


Physical3 => Logical Port2 for USB3.1 and USB2.0.


Physical4 => Logical Port3 for USB3.1 and USB2.0.

1100011100002 Port USB 3.1 Hub
2 Port USB2.0 hub with permanently attached device on Port 2

Physical1 Not used.


Physical2 Not used.


Physical3 => Logical Port1 for USB3.1 and USB2.0.


Physical4 => Logical Port2 for USB3.1 and USB2.0.

0011111100101 Port USB 3.1 Hub
2 Port USB 2.0 Hub

Physical1 => Logical Port1 for USB3.1 and USB2.0.


Physical2 => Logical Port2 for USB2.0.


Physical3 Not Used.


Physical4 Not used.

1000111100101 Port USB 3.1 Hub
2 Port USB 2.0 Hub

Physical1 Not used.


Physical2 => Logical Port2 for USB2.0.


Physical3 Not used


Physical4 => Logical Port1 for USB3.1 and USB2.0.

1111111111101 Port USB 3.1 Hub
4 Port USB 2.0 Hub

Physical1 => Logical Port1 for USB3.1 and USB2.0.


Physical2 => Logical Port2 for USB2.0.


Physical3 => Logical Port3 for USB2.0.


Physical4 => Logical Port4 for USB2.0.

1010N/A0x0xInvalid combination when USB2_ONLY = 0000, 0001, 0100, or 0101. If invalid combination is used, then physical port 4 will not operate at USB3.1 Gen 1 speeds.
1011N/A0x01Invalid combination when USB2_ONLY = 0001 or 0101. If invalid combination is used, then physical port 4 will not operate at USB3.1 Gen 1 speeds.
1110N/A010xInvalid combination when USB2_ONLY = 0100 or 0101. If invalid combination is used, then physical port 4 will not operate at USB3.1 Gen 1 speeds.
1111N/A0101Invalid combination when USB2_ONLY = 0101. If invalid combination is used, then physical port 4 will not operate at USB3.1 Gen 1 speeds.

SMBus Slave Operation

When the SMBus interface mode is enabled, the TUSB8042 supports read block and write block protocols as a slave-only SMBus device.

The TUSB8042 slave address is 1000 1xyz, where:

  • x is the state of GANGED/SMBA2/HS_UP pin at reset,
  • y is the state of FULLPWRMGMTz/SMBA1/SS_UP pin at reset, and
  • z is the read/write bit; 1 = read access, 0 = write access.

If the TUSB8042 is addressed by a host using an unsupported protocol it will not respond. The TUSB8042 waits indefinitely for configuration by the SMBus host and will not connect on the upstream port until the SMBus host indicates configuration is complete by clearing the CFG_ACTIVE bit.

For details on SMBus requirements, refer to the System Management Bus Specification.

Register Maps

Configuration Registers

The internal configuration registers are accessed on byte boundaries. The configuration register values are loaded with defaults but can be over-written when the TUSB8042 is in I2C or SMBus mode.

Table 6. TUSB8042 Register Map

BYTE ADDRESSCONTENTSEEPROM CONFIGURABLE
00hROM Signature RegisterYes
01hVendor ID LSBYes
02hVendor ID MSBYes
03hProduct ID LSBYes
04hProduct ID MSBYes
05hDevice Configuration RegisterYes
06hBattery Charging Support RegisterYes
07hDevice Removable Configuration RegisterYes
08hPort Used Configuration RegisterYes
09hReserved. Must default to 00h. Yes
0AhDevice Configuration Register 2Yes
0BhUSB 2.0 Port Polarity Control RegisterYes
0Ch-0FhReservedNo
10h-1FhUUID Byte [15:0]No
20h-21hLangID Byte [1:0]Yes
22hSerial Number LengthYes
23hManufacturer String LengthYes
24hProduct String LengthYes
25hDevice Configuration Register 3Yes
26hUSB 2.0 Only Port RegisterYes
27h-2EhReservedYes
2FhReservedNo
30h-4FhSerial Number String Byte [31:0]Yes
50h-8FhManufacturer String Byte [63:0]Yes
90h-CFhProduct String Byte [63:0]Yes
D0h-D4hReservedYes(1)
D5h-D7hReservedNo
D8h-DChReservedYes(1)
DDh-EFhReservedNo
F0hAdditional Features Configuration RegisterYes
F1h-F7hReservedNo
F8hSMBus Device Status and Command RegisterNo
F9h - FFhReservedNo

ROM Signature Register

Figure 3. Register Offset 0h
Bit No.76543210
Reset State00000000

Table 7. Bit Descriptions – ROM Signature Register

BitFieldTypeDescription
7:0romSignatureRWROM Signature Register. This register is used by the TUSB8042 in I2C mode to validate the attached EEPROM has been programmed. The first byte of the EEPROM is compared to the mask 55h and if not a match, the TUSB8042 aborts the EEPROM load and executes with the register defaults.

Vendor ID LSB Register

Figure 4. Register Offset 1h
Bit No.76543210
Reset State01010001

Table 8. Bit Descriptions – Vendor ID LSB Register

BitFieldTypeDescription
7:0vendorIdLsbRO/RWVendor ID LSB. Least significant byte of the unique vendor ID assigned by the USB-IF; the default value of this register is 51h representing the LSB of the TI Vendor ID 0451h. The value may be over-written to indicate a customer Vendor ID.
Value used for this field will be the non-zero value written by EEPROM/SMBus to both PID and VID. If a zero value is written by EEPROM/SMbus to both PID and VID, then value used for this field will be the non-zero value from OTP. If a zero value is written by OTP, then value used for this field will be 51h.

Vendor ID MSB Register

Figure 5. Register Offset 2h
Bit No.76543210
Reset State00000100

Table 9. Bit Descriptions – Vendor ID MSB Register

BitFieldTypeDescription
7:0vendorIdMsbRO/RWVendor ID MSB. Most significant byte of the unique vendor ID assigned by the USB-IF; the default value of this register is 04h representing the MSB of the TI Vendor ID 0451h. The value may be over-written to indicate a customer Vendor ID.
Value used for this field will be the non-zero value written by EEPROM/SMBus to both PID and VID. If a zero value is written by EEPROM/SMbus to both PID and VID, then value used for this field will be the non-zero value from OTP. If a zero value is written by OTP, then value used for this field will be 04h.

Product ID LSB Register

Figure 6. Register Offset 3h
Bit No.76543210
Reset State01000000

Table 10. Bit Descriptions – Product ID LSB Register

BitFieldTypeDescription
7:0productIdLsbRO/RWProduct ID LSB. Least significant byte of the product ID assigned by Texas Instruments and reported in the SuperSpeed Device descriptor. the default value of this register is 40h representing the LSB of the SuperSpeed product ID assigned by Texas Instruments The value reported in the USB 2.0 Device descriptor is the value of this register bit wise XORed with 00000010b. The value may be over-written to indicate a customer product ID.
Value used for this field will be the non-zero value written by EEPROM/SMBus to both PID and VID. If a zero value is written by EEPROM/SMbus to both PID and VID, then value used for this field will be the non-zero value from OTP. If a zero value is written by OTP, then value used for this field will be 40h .

Product ID MSB Register

Figure 7. Register Offset 4h
Bit No.76543210
Reset State10000010

Table 11. Bit Descriptions – Product ID MSB Register

BitFieldTypeDescription
7:0productIdMsbRO/RWProduct ID MSB. Most significant byte of the product ID assigned by Texas Instruments; the default value of this register is 82h representing the MSB of the product ID assigned by Texas Instruments. The value may be over-written to indicate a customer product ID.
Value used for this field will be the non-zero value written by EEPROM/SMBus to both PID and VID. If a zero value is written by EEPROM/SMbus to both PID and VID, then value used for this field will be the non-zero value from OTP. If a zero value is written by OTP, then value used for this field will be 82h.

Device Configuration Register

Figure 8. Register Offset 5h
Bit No.76543210
Reset State0001XX00

Table 12. Bit Descriptions – Device Configuration Register

BitFieldTypeDescription
7customStringsRWCustom strings enable. This bit controls the ability to write to the Manufacturer String Length, Manufacturer String, Product String Length, Product String, and Language ID registers
0 = The Manufacturer String Length, Manufacturer String, Product String Length, Product String, and Language ID registers are read only
1 = The Manufacturer String Length, Manufacturer String, Product String Length, Product String, and Language ID registers may be loaded by EEPROM or written by SMBus
The default value of this bit is 0.
6customSernumRWCustom serial number enable. This bit controls the ability to write to the serial number registers.
0 = The Serial Number String Length and Serial Number String registers are read only
1 = Serial Number String Length and Serial Number String registers may be loaded by EEPROM or written by SMBus
The default value of this bit is 0.
5u1u2DisableRWU1 U2 Disable. This bit controls the U1/U2 support.
0 = U1/U2 support is enabled
1 = U1/U2 support is disabled, the TUSB8042 will not initiate or accept any U1 or U2 requests on any port, upstream or downstream, unless it receives or sends a Force_LinkPM_Accept LMP. After receiving or sending an FLPMA LMP, it will continue to enable U1 and U2 according to USB 3.1 protocol until it gets a power-on reset or is disconnected on its upstream port.
When the TUSB8042 is in I2C mode, the TUSB8042 loads this bit from the contents of the EEPROM.
When the TUSB8042 is in SMBUS mode, the value may be over-written by an SMBus host.
4RSVDROReserved. This bit is reserved and returns 1 when read.
3gangedRWGanged. This bit is loaded at the de-assertion of reset with the value of the GANGED/SMBA2/HS_UP pin.
0 = When fullPwrMgmtz = 0, each port is individually power switched and enabled by the PWRCTL[4:1]/BATEN[4:1] pins
1 = When fullPwrMgmtz = 0, the power switch control for all ports is ganged and enabled by the PWRCTL[4:1]/BATEN1 pin
When the TUSB8042 is in I2C mode, the TUSB8042 loads this bit from the contents of the EEPROM.
When the TUSB8042 is in SMBUS mode, the value may be over-written by an SMBus host.
2fullPwrMgmtzRWFull Power Management. This bit is loaded at the de-assertion of reset with the value of the FULLPWRMGMTz/SMBA1/SS_UP pin.
0 = Port power switching status reporting is enabled
1 = Port power switching status reporting is disabled
When the TUSB8042 is in I2C mode, the TUSB8042 loads this bit from the contents of the EEPROM.
When the TUSB8042 is in SMBUS mode, the value may be over-written by an SMBus host.
1u1u2TimerOvrRWU1 U2 Timer Override. When this field is set, the TUSB8042 will override the downstream ports U1/U2 timeout values set by USB3.1 Host software. If software sets value in the range of 1h - FFh, the TUSB8042 will use the value of FFh. If software sets value to 0, then TUSB8042 will use value of 0.
0RSVDROReserved. This field is reserved and returns 0 when read.

Battery Charging Support Register

Figure 9. Register Offset 6h
Bit No.76543210
Reset State0000XXXX

Table 13. Bit Descriptions – Battery Charging Support Register

BitFieldTypeDescription
7:4RSVDROReserved. Read only, returns 0 when read.
3:0batEn[3:0]RWBattery Charger Support. The bits in this field indicate whether the downstream port implements the charging port features.
0 = The port is not enabled for battery charging support features
1 = The port is enabled for battery charging support features
Each bit corresponds directly to a downstream port, i.e. batEn0 corresponds to downstream port 1, and batEN1 corresponds to downstream port 2.
The default value for these bits are loaded at the de-assertion of reset with the value of PWRCTL/BATEN[3:0].
When in I2C/SMBus mode the bits in this field may be over-written by EEPROM contents or by an SMBus host.

Device Removable Configuration Register

Figure 10. Register Offset 7h
Bit No.76543210
Reset State0000XXXX

Table 14. Bit Descriptions – Device Removable Configuration Register

BitFieldTypeDescription
7customRmblRWCustom Removable. This bit controls the ability to write to the port removable bits, port used bits, and USB2_ONLY bits.
0 = rmbl[3:0], used[3:0], and USB2_ONLY[3:0] are read only and the values are loaded from the OTP ROM
1 = rmbl[3:0], used[3:0], and USB2_ONLY[3:0] are read/write and can be loaded by EEPROM or written by SMBus
This bit may be written simultaneously with rmbl[3:0].
6:4RSVDROReserved. Read only, returns 0 when read.
3:0rmbl[3:0]RO/RWRemovable. The bits in this field indicate whether a device attached to downstream ports 4 through 1 are removable or permanently attached.
0 = The device attached to the port is not removable
1 = The device attached to the port is removable
Each bit corresponds directly to a downstream port n + 1, i.e. rmbl0 corresponds to downstream port 1, rmbl1 corresponds to downstream port 2, etc.
This field is read only unless the customRmbl bit is set to 1. Otherwise the value of this filed reflects the inverted values of the OTP ROM non_rmb[3:0] field.

Port Used Configuration Register

Figure 11. Register Offset 8h
Bit No.76543210
Reset State00001111

Table 15. Bit Descriptions – Port Used Configuration Register

BitFieldTypeDescription
7:4RSVDROReserved. Read only.
3:0used[3:0]RO/RWUsed. The bits in this field indicate whether a port is enabled.
0 = The port is not used or disabled
1 = The port is used or enabled
Each bit corresponds directly to a downstream port, i.e. used0 corresponds to downstream port 1, used1 corresponds to downstream port 2, etc. All combinations are supported with the exception of both ports 1 and 3 marked as disabled. This field is read only unless the customRmbl bit is set to 1. When the corresponding USB2_ONLY bit is set, the USB2 port will be used and enabled regardless of the bit programmed into this field.

Device Configuration Register 2

Figure 12. Register Offset Ah
Bit No.76543210
Reset State00X10000

Table 16. Bit Descriptions – Device Configuration Register 2

BitFieldTypeDescription
7ReservedROReserved. Read-only, returns 0 when read.
6customBCfeaturesRWCustom Battery Charging Feature Enable. This bit controls the ability to write to the battery charging feature configuration controls.
0 = The HiCurAcpModeEn is read only and the values are loaded from the OTP ROM.
1 = The HiCurAcpModeEn bit is read/write and can be loaded by EEPROM or written by SMBus.
This bit may be written simultaneously with HiCurAcpModeEn.
5pwrctlPolRWPower enable polarity. This bit is loaded at the de-assertion of reset with the value of the PWRCTL_POL pin.
0 = PWRCTL polarity is active low
1 = PWRCTL polarity is active high
When the TUSB8042 is in I2C mode, the TUSB8042 loads this bit from the contents of the EEPROM.
When the TUSB8042 is in SMBUS mode, the value may be over-written by an SMBus host.
4HiCurAcpModeEnRO/RWHigh-current ACP mode enable. This bit enables the high-current tablet charging mode when the automatic battery charging mode is enabled for downstream ports.
0 = High current divider mode disabled . High current is ACP2 (default)
1 = High current divider mode enabled. High current mode is ACP3
This bit is read only unless the customBCfeatures bit is set to 1. If customBCfeatures is 0, the value of this bit reflects the value of the OTP ROM HiCurAcpModeEn bit.
3:2ReservedRWReserved
1autoModeEnzRWAutomatic Mode Enable. This bit is loaded at the de-assertion of reset with the value of the AUTOENz/HS_SUSPEND pin.
The automatic mode only applies to downstream ports with battery charging enabled when the upstream port is not connected. Under these conditions:
0 = Automatic mode battery charging features are enabled.
1 = Automatic mode is disabled; only Battery Charging DCP and CDP mode is supported.
NOTE: When the upstream port is connected, Battery Charging CDP mode will be supported on all ports that are enabled for battery charging support regardless of the value of this bit.
0RSVDROReserved. Read only, returns 0 when read.

USB 2.0 Port Polarity Control Register

Figure 13. Register Offset Bh
Bit No.76543210
Reset State00000000

Table 17. Bit Descriptions – USB 2.0 Port Polarity Control Register

BitFieldTypeDescription
7customPolarityRWCustom USB 2.0 Polarity. This bit controls the ability to write the p[4:0]_usb2pol bits.
0 = The p[4:0]_usb2pol bits are read only and the values are loaded from the OTP ROM.
1 = The p[4:0]_usb2pol bits are read/write and can be loaded by EEPROM or written by SMBus.
This bit may be written simultaneously with the p[4:0]_usb2pol bits
6:5RSVDROReserved. Read only, returns 0 when read.
4p4_usb2polRO/RWDownstream Port 4 DM/DP Polarity. This controls the polarity of the port.
0 = USB 2.0 port polarity is as documented by the pin out
1 = USB 2.0 port polarity is swapped from that documented in the pin out, i.e. DM becomes DP, and DP becomes DM.
This bit is read only unless the customPolarity bit is set to 1. If customPolarity is 0 the value of this bit reflects the value of the OTP ROM p4_usb2pol bit.
3p3_usb2polRO/RWDownstream Port 3 DM/DP Polarity. This controls the polarity of the port.
0 = USB 2.0 port polarity is as documented by the pin out
1 = USB 2.0 port polarity is swapped from that documented in the pin out, i.e. DM becomes DP, and DP becomes DM.
This bit is read only unless the customPolarity bit is set to 1. If customPolarity is 0 the value of this bit reflects the value of the OTP ROM p3_usb2pol bit.
2p2_usb2polRO/RWDownstream Port 2 DM/DP Polarity. This controls the polarity of the port.
0 = USB 2.0 port polarity is as documented by the pin out
1 = USB 2.0 port polarity is swapped from that documented in the pin out, i.e. DM becomes DP, and DP becomes DM.
This bit is read only unless the customPolarity bit is set to 1. If customPolarity is 0 the value of this bit reflects the value of the OTP ROM p2_usb2pol bit.
1p1_usb2polRORWDownstream Port 1 DM/DP Polarity. This controls the polarity of the port.
0 = USB 2.0 port polarity is as documented by the pin out
1 = USB 2.0 port polarity is swapped from that documented in the pin out, i.e. DM becomes DP, and DP becomes DM.
This bit is read only unless the customPolarity bit is set to 1. If customPolarity is 0 the value of this bit reflects the value of the OTP ROM p1_usb2pol bit.
0p0_usb2polRO/RWUpstream Port DM/DP Polarity. This controls the polarity of the port.
0 = USB 2.0 port polarity is as documented by the pin out
1 = USB 2.0 port polarity is swapped from that documented in the pin out, i.e. DM becomes DP, and DP becomes DM.
This bit is read only unless the customPolarity bit is set to 1. If customPolarity is 0 the value of this bit reflects the value of the OTP ROM p0_usb2pol bit.

UUID Registers

Figure 14. Register Offset 10h-1Fh
Bit No.76543210
Reset StateXXXXXXXX

Table 18. Bit Descriptions – UUID Byte N Register

BitFieldTypeDescription
7:0uuidByte[n]ROUUID byte N. The UUID returned in the Container ID descriptor. The value of this register is provided by the device and is meets the UUID requirements of Internet Engineering Task Force (IETF) RFC 4122 A UUID URN Namespace.

Language ID LSB Register

Figure 15. Register Offset 20h
Bit No.76543210
Reset State00001001

Table 19. Bit Descriptions – Language ID LSB Register

BitFieldTypeDescription
7:0langIdLsbRO/RWLanguage ID least significant byte. This register contains the value returned in the LSB of the LANGID code in string index 0. The TUSB8042 only supports one language ID. The default value of this register is 09h representing the LSB of the LangID 0409h indicating English United States.
When customStrings is 1, this field may be over-written by the contents of an attached EEPROM or by an SMBus host.

Language ID MSB Register

Figure 16. Register Offset 21h
Bit No.76543210
Reset State00000000

Table 20. Bit Descriptions – Language ID MSB Register

BitFieldTypeDescription
7:0langIdMsbRO/RWLanguage ID most significant byte. This register contains the value returned in the MSB of the LANGID code in string index 0. The TUSB8042 only supports one language ID. The default value of this register is 04h representing the MSB of the LangID 0409h indicating English United States.
When customStrings is 1, this field may be over-written by the contents of an attached EEPROM or by an SMBus host.

Serial Number String Length Register

Figure 17. Register Offset 22h
Bit No.76543210
Reset State00011000

Table 21. Bit Descriptions – Serial Number String Length Register

BitFieldTypeDescription
7:6RSVDROReserved. Read only, returns 0 when read.
5:0serNumStringLenRO/RWSerial number string length. The string length in bytes for the serial number string. The default value is 18h indicating that a 24 byte serial number string is supported. The maximum string length is 32 bytes.
When customSernum is 1, this field may be over-written by the contents of an attached EEPROM or by an SMBus host.
When the field is non-zero, a serial number string of serNumbStringLen bytes is returned at string index 1 from the data contained in the Serial Number String registers.

Manufacturer String Length Register

Figure 18. Register Offset 23h
Bit No.76543210
Reset State00000000

Table 22. Bit Descriptions – Manufacturer String Length Register

BitFieldTypeDescription
7RSVDROReserved. Read only, returns 0 when read.
6:0mfgStringLenRO/RWManufacturer string length. The string length in bytes for the manufacturer string. The default value is 0, indicating that a manufacturer string is not provided. The maximum string length is 64 bytes.
When customStrings is 1, this field may be over-written by the contents of an attached EEPROM or by an SMBus host.
When the field is non-zero, a manufacturer string of mfgStringLen bytes is returned at string index 3 from the data contained in the Manufacturer String registers.

Product String Length Register

Figure 19. Register Offset 24h
Bit No.76543210
Reset State00000000

Table 23. Bit Descriptions – Product String Length Register

BitFieldTypeDescription
7RSVDROReserved. Read only, returns 0 when read.
6:0prodStringLenRO/RWProduct string length. The string length in bytes for the product string. The default value is 0, indicating that a product string is not provided. The maximum string length is 64 bytes.
When customStrings is 1, this field may be over-written by the contents of an attached EEPROM or by an SMBus host.
When the field is non-zero, a product string of prodStringLen bytes is returned at string index 3 from the data contained in the Product String registers.

Device Configuration Register 3

Figure 20. Register Offset 25h
Bit No.76543210
Reset State00000000

Table 24. Bit Descriptions – Device Configuration Register 3

BitFieldTypeDescription
7:5RSVDROReserved. Read only, returns 0 when read.
4USB2.0_onlyRWUSB 2.0 hub reports as 2.0 only. This bit disables the USB 2.0 hub from reporting 5Gbps support in the wSpeedsSupported field of the USB SS BOS SS device capability descriptor. This bit will also disable the USB3.0 hub.
This bit is read/write but the read value returned is the Boolean OR of this bit and the corresponding eFuse bit. If either bit is set, this feature is enabled.
3ReservedROSwitch to reserved
2I2C_100kR/WI2C 100kHz. This bit controls the clock rate of the I2C master for both USB to I2C requests . The EEPROM reads will occur at 400K unless eFuse is used to set the rate to 100k.
This bit is read/write but the read value returned is the Boolean OR of this bit and the corresponding eFuse bit. If either bit is set, this feature is enabled.
1Galaxy_EnzR/WDisable Galaxy compatible modes. When this field is high, Galaxy charging compatible mode will not be included in AUTOMODE charger sequence.
This bit is read/write but the read value returned is the Boolean OR of this bit and the corresponding eFuse bit. If either bit is set, this feature is disabled.
0FullAutoEnR/WEnable all divider battery charging modes. When automode is enabled and this bit is set, any DS port enabled for battery charging will attempt all divider battery charging modes before DCP, starting with the highest current option.
The bit is writable, but the value read back is the Boolean OR of this bit and the corresponding eFuse control.
If either bit is set, eFuse or this register, this feature is enabled.

USB 2.0 Only Port Register

Figure 21. Register Offset 26h
Bit No.76543210
Reset State00000000

Table 25. Bit Descriptions – USB 2.0 Only Port Register

BitFieldTypeDescription
7:4RSVDROReserved. Read only, returns 0 when read.
3:0USB2_ONLY[3:0]RO/RWUSB 2.0 Only Ports. The bits in this field primarily indicate whether a port is enabled only for USB 2.0 operation. This field is read-only unless customRmbl bit is set. Also, these bits will override the corresponding USED bit.
A value of 0 indicates the hub port is enabled for both USB 3.1 and USB 2.0.
A value of 1 indicates the hub port is enabled only for USB 2.0 operation.

Serial Number String Registers

Figure 22. Register Offset 30h-4Fh
Bit No.76543210
Reset StateXXxxxxxx

Table 26. Bit Descriptions – Serial Number Registers

BitFieldTypeDescription
7:0serialNumber[n]RO/RWSerial Number byte N. The serial number returned in the Serial Number string descriptor at string index 1. The default value of these registers is assigned by TI. When customSernum is 1, these registers may be over-written by EEPROM contents or by an SMBus host.

Manufacturer String Registers

Figure 23. Register Offset 50h-8Fh
Bit No.76543210
Reset State00000000

Table 27. Bit Descriptions – Manufacturer String Registers

BitFieldTypeDescription
7:0mfgStringByte[n]RWManufacturer string byte N. These registers provide the string values returned for string index 3 when mfgStringLen is greater than 0. The number of bytes returned in the string is equal to mfgStringLen.
The programmed data should be in UNICODE UTF-16LE encodings as defined by The Unicode Standard, Worldwide Character Encoding, Version 5.0.

Product String Registers

Figure 24. Register Offset 90h-CFh
Bit No.76543210
Reset State00000000

Table 28. Bit Descriptions – Product String Byte N Register

BitFieldTypeDescription
7:0prodStringByte[n]RO/RWProduct string byte N. These registers provide the string values returned for string index 2 when prodStringLen is greater than 0. The number of bytes returned in the string is equal to prodStringLen.
The programmed data should be in UNICODE UTF-16LE encodings as defined by The Unicode Standard, Worldwide Character Encoding, Version 5.0.

Additional Feature Configuration Register

Figure 25. Register Offset F0h
Bit No.76543210
Reset State00000000

Table 29. Bit Descriptions – Additional Feature Configuration Register

BitFieldTypeDescription
7:5ReservedRWReserved. This field defaults to 3'b000 and must not be changed.
4stsOutputEn RWStatus output enable. This field when set enables of the Status output signals, HS_UP, HS_SUSPEND, SS_UP, SS_SUSPEND.
0 = STS outputs are disabled.
1 = STS outputs are enabled.
This bit may be loaded by EEPROM or over-written by a SMBUS host.
3:1pwronTimeRWPower On Delay Time. When the efuse_pwronTime field is all 0s, this field sets the delay time from the removal disable of PWRCTL to the enable of PWRCTL when transitioning battery charging modes. For example, when disabling the power on a transition from ACP to DCP Mode. The nominal timing is defined as follows:
Equation 1. TPWRON_EN = (pwronTime x 1) x 200 ms

This field may be over-written by EEPROM contents or by an SMBus host.
0usb3spreadDisRW USB3 Spread Spectrum Disable. This bit allows firmware to disable the spread spectrum function of the USB3 phy PLL.
0 = Spread spectrum function is enabled
1= Spread spectrum function is disabled
This bit may be loaded by EEPROM or over-written by a SMBUS host.

SMBus Device Status and Command Register

Figure 26. Register Offset F8h
Bit No.76543210
Reset State00000000

Table 30. Bit Descriptions – SMBus Device Status and Command Register

BitFieldTypeDescription
7:2RSVDROReserved. Read only, returns 0 when read.
1smbusRstRSUSMBus interface reset. This bit loads the registers back to their GRSTz values. Note, that since this bit can only be set when in SMBus mode the cfgActive bit is also reset to 1. When software sets this bit it must reconfigure the registers as necessary.
This bit is set by writing a 1 and is cleared by hardware on completion of the reset. A write of 0 has no effect.
0cfgActiveRCUConfiguration active. This bit indicates that configuration of the TUSB8042 is currently active. The bit is set by hardware when the device enters the I2C or SMBus mode. The TUSB8042 shall not connect on the upstream port while this bit is 1.
When in I2C mode, the bit is cleared by hardware when the TUSB8042 exits the I2C mode.
When in the SMBus mode, this bit must be cleared by the SMBus host in order to exit the configuration mode and allow the upstream port to connect.
The bit is cleared by a writing 1. A write of 0 has no effect.