SMSC USB2512 User Manual

USB2512

USB 2.0 High-Speed
2-Port Hub Controller

PRODUCT FEATURES

General Description

The SMSC 2-Port Hub is a low power, OEM
configurable, STT (Single transaction translator) hub
controller IC with 2 downstream ports for embedded
USB solutions. The 2-port hub is fully compliant with the
USB 2.0 Specification and will attach to an upstream
port as a Full-Speed Hub or as a Full-/High-Speed Hub.
The 2-Port Hub supports Low-Speed, Full- Speed, and
High-Speed (if operating as a High-Speed Hub)
downstream devices on all of the enabled downstream
ports.

General Features

 Hub Controller IC with 2 downstream ports
 Enhanced OEM configuration options available

through either a single serial I2C EEPROM, or
SMBus Slave Port

 36-pin (6x6mm) QFN lead-free, RoHS compliant

package

Hardware Features

 Low power operation
 Full Power Management with individual or ganged

power control of each downstream port

 On-chip Power On Reset (POR)
 Internal 1.8V Voltage Regulator
 Fully integrated USB termination and Pull-up/Pull-

down resistors

 On Board 24MHz Crystal Driver, Resonator or

External 24MHz clock input

 Enhanced EMI rejection and ESD protection

performance

OEM Selectable Features

 Customize Vendor ID, Product ID, and Device ID
 Select whether the hub is part of a compound device

(When any downstream port is permanently
hardwired to a USB peripheral device, the hub is part
of a compound device)

 Flexible port mapping and disable sequence. Ports

can be disabled/reordered in any order to support
multiple product SKUs. Hub will automatically reorder
the remaining ports to match the Host controller's
numbering scheme.

 Programmable USB differential-pair pin location.

Ease PCB layout by aligning USB signal lines directly
to connectors

Datasheet

 Programmable USB signal drive strength. Recover

USB signal integrity due to compromised system
environment using 2-level driving strength resolution

 Select the presence of a permanently hardwired USB

peripheral device on a port by port basis

 Configure the delay time for filtering the over-current

sense inputs

 Configure the delay time for turning on downstream

port power

 Indicate the maximum current that the 2-port hub

consumes from the USB upstream port

 Indicate the maximum current required for the hub

controller

 Pin Selectable Options for Default Configuration

— Select Downstream Ports as Non-Removable Ports

Applications

 LCD monitors and TVs
 Multi-function USB peripherals
 PC mother boards
 Set-top boxes, DVD players, DVR/PVR
 Printers and scanners
 PC media drive bay
 Portable hub boxes
 Mobile PC docking
 Embedded systems

SMSC USB2512 DATASHEET Revision 1.92 (11-28-07)

USB 2.0 High-Speed 2-Port Hub Controller

ORDER NUMBER(S):

USB2512-AEZG FOR 36 PIN, QFN LEAD-FREE ROHS COMPLIANT PACKAGE

Datasheet

80 ARKAY DRIVE, HAUPPAUGE, NY 11788 [phone], FAX [phone]

Copyright © 2007 SMSC or its subsidiaries. All rights reserved.

Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications. Consequently, complete information sufficient for
construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC
reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications
before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent
rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated
version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors
known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not
designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property
damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of
this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered
trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders.

SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE
OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL
DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT;
TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD
TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Revision 1.92 (11-28-07) 2 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Table of Contents

Chapter 1 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Chapter 2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Chapter 3 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.1 PIN Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3.2 Buffer Type Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Chapter 4 Configuration Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1 2-Port Hub . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1.1 Hub Configuration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1.2 VBus Detect. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.2 EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.2.1 Internal Register Set (Common to EEPROM and SMBus) . . . . . . . . . . . . . . . . . . . . . . . 13

4.2.2 I2C EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

4.2.3 In-Circuit EEPROM Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.3 SMBus Slave Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.3.1 Bus Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.3.2 Invalid Protocol Response Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

4.3.3 General Call Address Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

4.3.4 Slave Device Time-Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

4.3.5 Stretching the SCLK Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.3.6 SMBus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.3.7 Bus Reset Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.3.8 SMBus Alert Response Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.4 Default Configuration Option: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.5 Default Strapping Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.6 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.6.1 Internal POR Hardware Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.6.2 External Hardware RESET_N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4.6.3 USB Bus Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Chapter 5 DC Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

5.1 Maximum Guaranteed Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

5.2 Recommended Operating Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Chapter 6 AC Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.1 Oscillator/Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.1.1 SMBus Interface: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.1.2 I2C EEPROM: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6.1.3 USB 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Chapter 7 Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

SMSC USB2512 3 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

List of Figures

Figure 1.1 USB2512 36-Pin QFN (Embedded Footprint) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 2.1 USB2512 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 4.1 Block Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 4.2 Block Read. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 4.3 Reset_N Timing for Default/Strap Option Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Figure 4.4 Reset_N Timing for EEPROM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 4.5 Reset_N Timing for SMBus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 6.1 Typical Crystal Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Figure 6.2 Formula to find value of C1 and C2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Figure 7.1 36-Pin QFN, 6x6mm Body, 0.5mm Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

SMSC USB2512 4 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

List of Tables

Table 3.1 USB2512 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 3.2 SMBus or EEPROM Interface Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 3.3 USB2512 Power, Ground, and No Connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Table 3.4 USB2512 Buffer Type Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Table 4.1 Internal Default, EEPROM and SMBus Register Memory Map. . . . . . . . . . . . . . . . . . . . . . . . 13

Table 4.2 Port Remap Register for Ports 1 & 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Table 4.3 Reset_N Timing for Default/Strap Option Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 4.4 Reset_N Timing for EEPROM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Table 4.5 Reset_N Timing for SMBus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Table 5.1 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Table 5.2 Pin Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

SMSC USB2512 5 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Chapter 1 Pin Configuration

SUSP_IND/LOCAL_PWR/NON_REM0

VDDA33

USBUP_DM

USBUP_DP

XTAL2

XTAL1/CLKIN

VDD18PLL

RBIAS

VDD33PLL

RESET_N24HS_IND/CFG_SEL123SCL/SMBCLK/CFG_SEL022SDA/SMBDATA/NON_REM121NC20NC

VBUS_DET

26

25

27

28

29

30

31

32

Embedded Footprint

33

(Top View QFN-36)

34

35

(must be connected to VSS)

36

1

USBDN1_DM

USB2512

Thermal Slug

2

3

USBDN1_DP

USBDN2_DM

SMSC

4

USBDN2_DP

VDD33

5NC6NC7NC8NC9

VDDA33

NC

19

18

17

16

15

14

13

12

11

10

NC

OCS2_N

PRTPWR2

VDD33CR

VDD18

OCS1_N

PRTPWR1

TEST

VDDA33

Indicates pins on the bottom of the device.

Figure 1.1 USB2512 36-Pin QFN (Embedded Footprint)

SMSC USB2512 6 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Chapter 2 Block Diagram

To Upstream

V

BUS

Bus-Power

Detect/V

BUS

Pulse

Upstream USB

Upstream

PHY

Repeater

Routing & Port Re-Ordering Logic

Data

24 MHz Crystal

3.3V

1.8V Reg

PLL

SIE

TT

1.8V

To EEPROM or

SMBus Master

SCKSD

Serial

Inte rface

Controller

Port

Controller

PHY#1

USB Data

Downstream

Port #1

OC

Sense

Switch

Driver

LED

Drivers

OC Sense

Switch/LED

Drivers

PHY#2

USB Data

Downstream

Figure 2.1 USB2512 Block Diagram

Port #2

OC

Sense

Switch

Driver

LED

Drivers

OC Sense

Switch/LED

Drivers

SMSC USB2512 7 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Chapter 3 Pin Descriptions

3.1 PIN Descriptions

This section provides a detailed description of each signal. The signals are arranged in functional
groups according to their associated interface.

The “N” symbol in the signal name indicates that the active, or asserted, state occurs when the signal
is at a low voltage level. When “N” is not present before the signal name, the signal is asserted when
at the high voltage level.

The terms assertion and negation are used exclusively. This is done to avoid confusion when working
with a mixture of “active low” and “active high” signals. The term assert, or assertion, indicates that a
signal is active, independent of whether that level is represented by a high or low voltage. The term
negate, or negation, indicates that a signal is inactive.

Table 3.1 USB2512 Pin Descriptions

SYMBOL

USBUP_DP

USBUP_DM

VBUS_DET 27

USBDN_DP[2:1]/

&

USBDN_DM[2:1]/

QFN-36

EMB

31
30

4
2

3
1

BUFFER

TYPE DESCRIPTION

UPSTREAM USB INTERFACES

IO-U USB Bus Data

These pins connect to the upstream USB bus data signals
(Host port, or upstream hub).

I/O12 Detect Upstream VBUS Power

Detects state of Upstream VBUS power. The SMSC Hub
monitors VBUS_DET to determine when to assert the internal
D+ pull-up resistor (signaling a connect event).

When designing a detachable hub, this pin must be connected
to the VBUS power pin of the USB port that is upstream of the
hub.

For self-powered applications with a permanently attached
host, this pin must be connected to 3.3V (typically VDD33).

DOWNSTREAM 2-PORT USB 2.0 INTERFACE

IO-U High-Speed USB Data

These pins connect to the downstream USB peripheral devices
attached to the hub’s port.

PRTPWR[2:1] 16

12

OCS[2:1]_N 17

13

RBIAS 35

SMSC USB2512 8 Revision 1.92 (11-28-07)

O12 USB Power Enable

Enables power to USB peripheral devices downstream.

Note: The hub supports active high power controllers only!

IPU Over Current Sense

Input from external current monitor indicating an over-current
condition.
{Note: Contains internal pull-up to 3.3V supply}

I-R USB Transceiver Bias

A 12.0kΩ (+/- 1%) resistor is attached from ground to this pin
to set the transceiver’s internal bias settings.

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Table 3.1 USB2512 Pin Descriptions (continued)

Datasheet

SYMBOL

SDA/

SMBDATA/

NON_REM1

SCL/

SMBCLK/

CFG_SEL0

QFN-36

EMB

22

24

BUFFER

TYPE DESCRIPTION

SERIAL PORT INTERFACE

I/OSD12 Serial Data / SMB Data & Port Non Removable Strap Option

NON_REM1: Non removable port strap
option.

If this strap is enabled by package and configuration settings
(see Ta bl e 3 .2 ), this pin will be sampled (in conjunction
with LOCAL_PWR/SUSP_IND/NON_REM0) at RESET_N
negation to determine if imports [2:1] contain permanently
attached
(non-removable) devices:

NON_REM[1:0] = ‘00’, All ports are removable.

NON_REM[1:0] = ‘01’, Port 1 is nonremovable.

NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable.

NON_REM[1:0] = ‘11’, Ports 1 & 2 are non-removable.

I/OSD12 Serial Clock (SCL)

SMBus Clock (SMBCLK)

Configuration Select_SEL0: The logic state of this multifunction
pin is internally latched on the rising edge of RESET_N
(RESET_N negation), and will determine the hub configuration
method as described in Table 3.2, "SMBus or EEPROM

Interface Behavior".

HS_IND/

CFG_SEL1

XTAL1/

CLKIN

25

33

I/O12 High-Speed Upstream port indictor & Configuration

Programming Select

HS_IND: High Speed Indicator for upstream port connection
speed.

The active state of the LED will be determined as follows:

CFG_SEL1 = ‘0’,
HS_IND is active high,

CFG_SEL1 = ‘1’,
HS_IND is active low,

‘Asserted’ = Hub is connected at HS
‘Negated’ = Hub is connected at FS

CFG_SEL1: The logic state of this pin is internally latched on
the rising edge of RESET_N (RESET_N negation), and will
determine the hub configuration method as described in

Table 3.2, "SMBus or EEPROM Interface Behavior".

MISC

ICLKx Crystal Input/External Clock Input

24MHz crystal or external clock input.
This pin connects to either one terminal of the crystal or to an
external 24MHz clock when a crystal is not used.

Revision 1.92 (11-28-07) 9 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Table 3.1 USB2512 Pin Descriptions (continued)

BUFFER

TYPE DESCRIPTION

SYMBOL

QFN-36

EMB

XTAL2 32 OCLKx Crystal Output

24MHz Crystal
This is the other terminal of the crystal, or a NO-CONNECT
when an external clock source is used to drive XTAL1/CLKIN.
This output must not be used to drive any external circuitry
other than the crystal circuit.

RESET_N 26

IS RESET Input

The system can reset the chip by driving this input low. The
minimum active low pulse is 1 us.

When the RESET_N pin is pulled to VDD33, the internal POR
(Power on Reset) is enabled and no external reset circuitry is
required. The internal POR holds the internal logic in reset until
the power supplies are stable.

SUSP_IND/

LOCAL_PWR/

NON_REM0

28

I/O Active/Suspend status LED or Local-Power & Non Removable

Strap Option

Suspend Indicator: Indicates USB state of the hub.
‘negated’ = Unconfigured, or configured and in USB Suspend
‘asserted’ = Hub is configured, and is active (i.e., not in
suspend)

Local Power: Detects availability of local self-power source.
Low = Self/local power source is NOT available (i.e., Hub gets
all power from Upstream USB VBus).
High = Self/local power source is available.

NON_REM0 Strap Option:
If this strap is enabled by package and configuration settings
(see Ta bl e 3 .2 ), this pin will be sampled (in conjunction with
NON_REM1) at RESET_N negation to determine if ports [2:1]
contain permanently attached (non-removable) devices. Also,
the active state of the LED
will be determined as follows:

NON_REM[1:0] = ‘00’, All ports are removable, and the LED is
active high

NON_REM[1:0] = ‘01’, Port 1 is nonremovable, and the LED is
active low

NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable, and the
LED is active high

NON_REM[1:0] = ‘11’, Ports 1 & 2 are non-removable, and the
LED is active low

TEST 11

IPD TEST pin

Used for testing the chip. User must treat as a no-connect or
connect to ground.

Table 3.2 SMBus or EEPROM Interface Behavior

CFG_SEL1 CFG_SEL0 SMBUS OR EEPROM INTERFACE BEHAVIOR

0 0 Internal Default Configuration

 Strap Options Enabled

SMSC USB2512 10 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Table 3.2 SMBus or EEPROM Interface Behavior (continued)

CFG_SEL1 CFG_SEL0 SMBUS OR EEPROM INTERFACE BEHAVIOR

Datasheet

0 1 Configured as an SMBus slave for external download of user-defined

1 0 Internal Default Configuration

1 1 2-Wire I2C EEPROMS are supported.

Table 3.3 USB2512 Power, Ground, and No Connect

PACKAGE SYMBOL 36-QFN EMB

VDD18 14

VDD33PLL 36

descriptors.

 SMBus slave address 58 (0101100x)
 Strap Options Disabled
 All Settings Controlled by Registers

 Strap Options Enabled
 Bus Power Operation

 Strap Options Disabled
 All Settings Controlled by Registers

FUNCTION

VDD Core

This pin must have a 1.0μF (or greater) ±20% (ESR <0.1Ω) capacitor to
VSS.

VDD 3.3 PLL Regulator Reference

+3.3V power supply for the PLL. If the internal PLL 1.8V regulator
is enabled, then this pin acts as the regulator input.

VDDPLL18 34 VDD PLL

This pin must have a 1.0μF (or greater) ±20% (ESR <0.1Ω) capacitor to
VSS.

VDDA33 5

10
29

VDD33/VDD33CR 23

15

VDD Analog I/O

+3.3V Filtered analog PHY power, shared between adjacent ports.

VDDIO/VDD 3.3 Core Regulator Reference

+3.3V power supply for the Digital I/O
If the internal core regulator is enabled, then VDD33CR acts as the
regulator input.

NC 6

No Connect
7
8

Leave unconnected on the circuit board.
9

18
19
20
21

Revision 1.92 (11-28-07) 11 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

3.2 Buffer Type Descriptions

Table 3.4 USB2512 Buffer Type Descriptions

BUFFER DESCRIPTION

I Input.

IPD Input with internal weak pull-down resistor.

IPU Input with internal weak pull-up resistor.

IS Input with Schmitt trigger.

O12 Output 12mA.

OD12 Open drain... 12mA sink.

I/O12 Input/Output buffer with 12mA sink and 12mA source.

I/OSD12

ICLKx XTAL clock input.

OCLKx XTAL clock output.

I-R RBIAS.

I/O-U Analog Input/Output Defined in USB specification.

AIO Analog Input/Output.

Open drain...12mA sink with Schmitt trigger, and must meet I2C-Bus Specification
Version 2.1 requirements.

SMSC USB2512 12 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Chapter 4 Configuration Options

4.1 2-Port Hub

SMSC’s USB 2.0 2-Port Hub is fully specification compliant to the Universal Serial Bus Specification
Revision 2.0 April 27,2000 (12/7/2000 and 5/28/2002 Errata). Please reference Chapter 10 (Hub
Specification) for general details regarding Hub operation and functionality.

The 2-Port Hub provides 1 Transaction Translator (TT) that is shared by both downstream ports
(defined as Single-TT configuration), The TT contains 4 non-periodic buffers.

4.1.1 Hub Configuration Options

The SMSC Hub supports a large number of features (some are mutually exclusive), and must be
configured in order to correctly function when attached to a USB host controller. There are three
principal ways to configure the hub: SMBus, EEPROM, or by internal default settings (with or without
pin strapping option over-rides). In all cases, the configuration method will be determined by the
CFG_SEL1 and CFG_SEL0 pins immediately after RESET_N negation.

4.1.1.1 Power Switching Polarity

The hub only supports “active high” port power controllers.

4.1.2 VBus Detect

According to Section 7.2.1 of the USB 2.0 Specification, a downstream port can never provide power
to its D+ or D- pull-up resistors unless the upstream port’s VBUS is in the asserted (powered) state.
The VBUS_DET pin on the Hub monitors the state of the upstream VBUS signal and will not pull-up
the D+ resistor if VBUS is not active. If VBUS goes from an active to an inactive state (Not Powered),
Hub will remove power from the D+ pull-up resistor within 10 seconds.

4.2 EEPROM Interface

The SMSC Hub can be configured via a 2-wire (I2C) EEPROM (256x8). (Please see Tab l e 3 . 1 for
specific details on how to enable configuration via an I2C EEPROM).

The Internal state-machine will (when configured for EEPROM support) read the external EEPROM for
configuration data. The hub will then “attach” to the upstream USB host.

Note: The Hub does not have the capacity to write, or “Program,” an external EEPROM. The Hub only
has the capability to read external EEPROMs. The external eeprom will be read (even if it is blank or
non-populated), and the hub will be “configured” with the values that are read.

Please see Internal Register Set (Common to EEPROM and SMBus) for a list of data fields available.

4.2.1 Internal Register Set (Common to EEPROM and SMBus)

Table 4.1 Internal Default, EEPROM and SMBus Register Memory Map

SMBUS AND

REG

ADDR R/W REGISTER NAME ABBR

00h R/W VID LSB VIDL 24h 0x00

01h R/W VID MSB VIDM 04h 0x00

02h R/W PID LSB PIDL 12h 0x00

SMSC USB2512 13 Revision 1.92 (11-28-07)

INTERNAL

DEFAULT ROM

EEPROM POR

VALUES

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Table 4.1 Internal Default, EEPROM and SMBus Register Memory Map (continued)

SMBUS AND

REG

ADDR R/W REGISTER NAME ABBR

03h R/W PID MSB PIDM 25h 0x00

04h R/W DID LSB DIDL 00h 0x00

05h R/W DID MSB DIDM 00h 0x00

06h R/W Config Data Byte 1 CFG1 8Bh 0x00

07h R/W Config Data Byte 2 CFG2 10h 0x00

08h R/W Config Data Byte 3 CFG3 00h 0x00

09h R/W Non-Removable Devices NRD 00h 0x00

0Ah R/W Port Disable (Self) PDS 08h 0x00

0Bh R/W Port Disable (Bus) PDB 08h 0x00

0Ch R/W Max Power (Self) MAXPS 01h 0x00

INTERNAL

DEFAULT ROM

EEPROM POR

VALUES

Datasheet

0Dh R/W Max Power (Bus) MAXPB 64h 0x00

0Eh R/W Hub Controller Max Current

(Self)

0Fh R/W Hub Controller Max Current

(Bus)

10h R/W Power-on Time PWRT 32h 0x00

11h-F5h R/W Reserved N/A 01h 0x00

F6h R/W Boost_Up BOOSTUP 00h 0x00

F7h R/W Reserved N/A 00h 0x00

F8h R/W Boost_2:0 BOOST20 00h 0x00

F9h R/W Reserved N/A 00h 0x00

FAh R/W Port Swap PRTSP 00h 0x00

FBh R/W Port Remap 12 PRTR12 00h 0x00

FC-FEh R/W Reserved N/A 00h 0x00

FFh R/W Status/Command

Note: SMBus register only

HCMCS 01h 0x00

HCMCB 64h 0x00

STCD 00h 0x00

4.2.1.1 Register 00h: Vendor ID (LSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 VID_LSB Least Significant Byte of the Vendor ID. This is a 16-bit value that uniquely

Revision 1.92 (11-28-07) 14 SMSC USB2512

identifies the Vendor of the user device (assigned by USB-Interface Forum).
This field is set by the OEM using either the SMBus or EEPROM interface
options.

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

4.2.1.2 Register 01h: Vendor ID (MSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 VID_MSB Most Significant Byte of the Vendor ID. This is a 16-bit value that uniquely

identifies the Vendor of the user device (assigned by USB-Interface Forum).
This field is set by the OEM using either the SMBus or EEPROM interface
options.

4.2.1.3 Register 02h: Product ID (LSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 PID_LSB Least Significant Byte of the Product ID. This is a 16-bit value that the Vendor

can assign that uniquely identifies this particular product (assigned by OEM).
This field is set by the OEM using either the SMBus or EEPROM interface
options.

4.2.1.4 Register 03h: Product ID (MSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 PID_MSB Most Significant Byte of the Product ID. This is a 16-bit value that the Vendor

can assign that uniquely identifies this particular product (assigned by OEM).
This field is set by the OEM using either the SMBus or EEPROM interface
options.

4.2.1.5 Register 04h: Device ID (LSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 DID_LSB Least Significant Byte of the Device ID. This is a 16-bit device release

number in BCD format (assigned by OEM). This field is set by the OEM
using either the SMBus or EEPROM interface options.

4.2.1.6 Register 05h: Device ID (MSB)

BIT

NUMBER BIT NAME DESCRIPTION

7:0 DID_MSB Most Significant Byte of the Device ID. This is a 16-bit device release

SMSC USB2512 15 Revision 1.92 (11-28-07)

number in BCD format (assigned by OEM). This field is set by the OEM
using either the SMBus or EEPROM interface options.

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

4.2.1.7 Register 06h: CONFIG_BYTE_1

BIT

NUMBER BIT NAME DESCRIPTION

7 SELF_BUS_PWR Self or Bus Power: Selects between Self- and Bus-Powered operation.

The Hub is either Self-Powered (draws less than 2mA of upstream bus
power) or Bus-Powered (limited to a 100mA maximum of upstream power
prior to being configured by the host controller).
When configured as a Bus-Powered device, the SMSC Hub consumes less
than 100mA of current prior to being configured. After configuration, the Bus­Powered SMSC Hub (along with all associated hub circuitry, any embedded
devices if part of a compound device, and 100mA per externally available
downstream port) must consume no more than 500mA of upstream VBUS
current. The current consumption is system dependent, and the OEM must
ensure that the USB 2.0 specifications are not violated.
When configured as a Self-Powered device, <1mA of upstream VBUS
current is consumed and all ports are available, with each port being capable
of sourcing 500mA of current.
This field is set by the OEM using either the SMBus or EEPROM interface
options.
Please see the description under Dynamic Power for the self/bus power
functionality when dynamic power switching is enabled.

Datasheet

0 = Bus-Powered operation
1 = Self-Powered operation

Note: If Dynamic Power Switching is enabled, this bit is ignored and the
LOCAL_PWR pin is used to determine if the hub is operating from self or
bus power.

6 Reserved Reserved

5 HS_DISABLE High Speed Disable: Disables the capability to attach as either a High/Full-

4 Reserved Reserved

3 EOP_DISABLE EOP Disable: Disables EOP generation of EOF1 when in Full-Speed mode.

2:1 CURRENT_SNS Over Current Sense: Selects current sensing on a port-by-port basis, all

speed device, and forces attachment as Full-speed only (i.e. no High-Speed
support).

0 = High-/Full-Speed
1 = Full-Speed-Only (High-Speed disabled!)

During FS operation only, this permits the Hub to send EOP if no
downstream traffic is detected at EOF1. See Section 11.3.1 of the USB 2.0
Specification for additional details. Note: generation of an EOP at the EOF1
point may prevent a Host controller (operating in FS mode) from placing the
USB bus in suspend.

0 = EOP generation is normal
1 = EOP generation is disabled

ports ganged, or none (only for bus-powered hubs). The ability to support
current sensing on a port or ganged basis is hardware implementation
dependent.

00 = Ganged sensing (all ports together)
01 = Individual port-by-port
1x = Over current sensing not supported (must only be used with Bus­Powered configurations!)

Revision 1.92 (11-28-07) 16 SMSC USB2512

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USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

BIT

NUMBER BIT NAME DESCRIPTION

0 PORT_PWR Port Power Switching: Enables power switching on all ports simultaneously

(ganged), or port power is individually switched on and off on a port- by-port
basis (individual). The ability to support power enabling on a port or ganged
basis is hardware implementation dependent.

0 = Ganged switching (all ports together)
1 = Individual port-by-port switching

4.2.1.8 Register 07h: Configuration Data Byte 2

BIT

NUMBER BIT NAME DESCRIPTION

7 DYNAMIC Dynamic Power Enable: Controls the ability of the Hub to automatically

change from Self-Powered operation to Bus-Powered operation if the local
power source is removed or is unavailable (and from Bus-Powered to Self­Powered if the local power source is restored). {Note: If the local power
source is available, the Hub will always switch to Self-Powered operation.}
When Dynamic Power switching is enabled, the Hub detects the availability
of a local power source by monitoring the external LOCAL_PWR pin. If the
Hub detects a change in power source availability, the Hub immediately
disconnects and removes power from all downstream devices and
disconnects the upstream port. The Hub will then re-attach to the upstream
port as either a Bus-Powered Hub (if local-power is unavailable) or a Self­Powered Hub (if local power is available).

0 = No Dynamic auto-switching
1 = Dynamic Auto-switching capable

6 Reserved Reserved

5:4 OC_TIMER OverCurrent Timer: Over Current Timer delay.

00 = 0.1ms
01 = 4ms
10 = 8ms
11 = 1 6 m s

3 COMPOUND

Compound Device: Allows the OEM to indicate that the Hub is part
of a compound (see the USB Specification for definition) device. The
applicable port(s) must also be defined as having a "Non-Removable
Device".
Note: When configured via strapping options, declaring a port as
non-removable automatically causes the hub controller to report that
it is part of a compound device.

0 = No
1 = Yes, Hub is part of a compound device

2:0 Reserved Reserved

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DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

4.2.1.9 Register 08h: Configuration Data Byte 3

BIT

NUMBER BIT NAME DESCRIPTION

7:4 Reserved Reserved

Datasheet

3 PRTMAP_EN Port Re-mapping enable: Selects the method used by the hub to assign port

2:0 Reserved Reserved

numbers and disable ports.

‘0’ = Standard Mode

‘1’ = Port Re-map mode

4.2.1.10 Register 09h: Non-Removable Device

BIT

NUMBER BIT NAME DESCRIPTION

7:0 NR_DEVICE Non-Removable Device: Indicates which port(s) include non-removable

devices. ‘0’ = port is removable, ‘1’ = port is non-removable.

Informs the Host if one of the active ports has a permanent device that is
undetachable from the Hub. (Note: The device must provide its own
descriptor data.)

When using the internal default option, the NON_REM[1:0] pins will
designate the appropriate ports as being non- removable.

Bit 7= Reserved, always = ‘0’
Bit 6= Reserved, always = ‘0’
Bit 5= Reserved, always = ‘0’
Bit 4= Reserved, always = ‘0’
Bit 3= Reserved, always = ‘1’
Bit 2= 1; Port 2 non-removable
Bit 1= 1; Port 1 non removable
Bit 0= Reserved, always = ‘0’

Revision 1.92 (11-28-07) 18 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

4.2.1.11 Register 0Ah: Port Disable For Self Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

7:0 PORT_DIS_SP Port Disable Self-Powered: Disables 1 or more contiguous ports. ‘0’ = port

is available, ‘1’ = port is disabled.

During Self-Powered operation

(PRTMAP_EN='0'),

disabled, and are not available to be enabled or enumerated by a Host
Controller. The ports can be disabled in any order, the internal logic will
automatically report the correct number of enabled ports to the USB Host,
and will reorder the active ports in order to ensure proper function.

Bit 7= Reserved, always = ‘0’
Bit 6= Reserved, always = ‘0’
Bit 5= Reserved, always = ‘0’
Bit 4= Reserved, always = ‘0’
Bit 3= Reserved, always = ‘1’
Bit 2= 1; Port 2 is disabled
Bit 1= 1; Port 1 is disabled
Bit 0= Reserved, always = ‘0’

this selects the ports which will be permanently

when remapping mode is disabled

4.2.1.12 Register 0Bh: Port Disable For Bus Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

7:0 PORT_DIS_BP Port Disable Bus-Powered: Disables 1 or more contiguous ports. ‘0’ = port

is available, ‘1’ = port is disabled.

During Self-Powered operation

(PRTMAP_EN='0'),

disabled, and are not available to be enabled or enumerated by a Host
Controller. The ports can be disabled in any order, the internal logic will
automatically report the correct number of enabled ports to the USB Host,
and will reorder the active ports in order to ensure proper function.

this selects the ports which will be permanently

when remapping mode is disabled

When using the internal default option, the PRT_DIS[1:0] pins will disable the
appropriate ports.

Bit 7= Reserved
Bit 6= Reserved
Bit 5= Reserved
Bit 4= Reserved
Bit 3= Reserved, always = ‘1’
Bit 2= 1; Port 2 is disabled
Bit 1= 1; Port 1 is disabled
Bit 0 is Reserved, always = ‘0’

4.2.1.13 Register 0Ch: Max Power For Self Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

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DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

7:0 MAX_PWR_SP Max Power Self_Powered: Value in 2mA increments that the Hub consumes

from an upstream port (VBUS) when operating as a self-powered hub. This
value includes the hub silicon along with the combined power consumption
(from VBUS) of all associated circuitry on the board. This value also includes
the power consumption of a permanently attached peripheral if the hub is
configured as a compound device, and the embedded peripheral reports
0mA in its descriptors.

Note: The USB 2.0 Specification does not permit this value to exceed

100mA

4.2.1.14 Register 0Dh: Max Power For Bus Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

7:0 MAX_PWR_BP Max Power Bus_Powered: Value in 2mA increments that the Hub consumes

from an upstream port (VBUS) when operating as a bus-powered hub. This
value includes the hub silicon along with the combined power consumption
(from VBUS) of all associated circuitry on the board. This value also includes
the power consumption of a permanently attached peripheral if the hub is
configured as a compound device, and the embedded peripheral reports
0mA in its descriptors.

4.2.1.15 Register 0Eh: Hub Controller Max Current For Self Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

7:0 HC_MAX_C_SP Hub Controller Max Current Self-Powered: Value in 2mA increments that the

Hub consumes from an upstream port (VBUS) when operating as a self­powered hub. This value includes the hub silicon along with the combined
power consumption (from VBUS) of all associated circuitry on the board.
This value does NOT include the power consumption of a permanently
attached peripheral if the hub is configured as a compound device.

Note: The USB 2.0 Specification does not permit this value to exceed

100mA

A value of 50 (decimal) indicates 100mA, which is the default value.

4.2.1.16 Register 0Fh: Hub Controller Max Current For Bus Powered Operation

BIT

NUMBER BIT NAME DESCRIPTION

7:0 HC_MAX_C_BP Hub Controller Max Current Bus-Powered: Value in 2mA increments that the

Hub consumes from an upstream port (VBUS) when operating as a bus­powered hub. This value will include the hub silicon along with the combined
power consumption (from VBUS) of all associated circuitry on the board.
This value will NOT include the power consumption of a permanently
attached peripheral if the hub is configured as a compound device.

A value of 50 (decimal) would indicate 100mA, which is the default value.

Revision 1.92 (11-28-07) 20 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

4.2.1.17 Register 10h: Power-On Time

BIT

NUMBER BIT NAME DESCRIPTION

7:0 POWER_ON_TIME Power On Time: The length of time that it takes (in 2 ms intervals) from the

time the host initiated power-on sequence begins on a port until power is
good on that port.

4.2.1.18 Register F6h: Boost_Up

BIT

NUMBER BIT NAME DESCRIPTION

7:2 Reserved Reserved

1:0 BOOST_IOUT USB electrical signaling drive strength Boost Bit for the Upstream Port.

‘00’ = Normal electrical drive strength = No boost
‘01’ = Elevated electrical drive strength = Low (approximately 4% boost)
‘10’ = Elevated electrical drive strength = Medium (approximately 8% boost)
‘11’ = Elevated electrical drive strength = High (approximately 12% boost)

Note: “Boost” could result in non-USB Compliant parameters (one

example would be Test J/K levels), the OEM should use a 00 value
unless specific implementation issues require additional signal
boosting to correct for degraded USB signalling levels.

4.2.1.19 Register F8h: Boost_2:0

BIT

NUMBER BIT NAME DESCRIPTION

7:4 Reserved Reserved

3:2 BOOST_IOUT_2 USB electrical signaling drive strength Boost Bit for Downstream Port ‘2’.

‘00’ = Normal electrical drive strength = No boost
‘01’ = Elevated electrical drive strength = Low (approximately 4% boost)
‘10’ = Elevated electrical drive strength = Medium (approximately 8% boost)
‘11’ = Elevated electrical drive strength = High (approximately 12% boost)

Note: “Boost” could result in non-USB Compliant parameters (one

example would be Test J/K levels), the OEM should use a 00 value
unless specific implementation issues require additional signal
boosting to correct for degraded USB signalling levels.

1:0 BOOST_IOUT_1 USB electrical signaling drive strength Boost Bit for Downstream Port ‘1’.

‘00’ = Normal electrical drive strength = No boost
‘01’ = Elevated electrical drive strength = Low (approximately 4% boost)
‘10’ = Elevated electrical drive strength = Medium (approximately 8% boost)
‘11’ = Elevated electrical drive strength = High (approximately 12% boost)

Note: “Boost” could result in non-USB Compliant parameters (one

example would be Test J/K levels), the OEM should use a 00 value
unless specific implementation issues require additional signal
boosting to correct for degraded USB signalling levels.

SMSC USB2512 21 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

4.2.1.20 Register FAh: Port Swap

BIT

NUMBER BIT NAME DESCRIPTION

Datasheet

7:0 PRTSP Port Swap: Swaps the Upstream and Downstream USB DP and DM Pins for

ease of board routing to devices and connectors.

‘0’ = USB D+ functionality is associated with the DP pin and D- functionality
is associated with the DM pin.

‘1’ = USB D+ functionality is associated with the DM pin and D- functionality
is associated with the DP pin.

Bit 7= Reserved
Bit 6= Reserved
Bit 5= Reserved
Bit 4= Reserved
Bit 3= Reserved
Bit 2= ‘1’; Port 2 DP/DM is Swapped.
Bit 1= ‘1’: Port 1 DP/DM is Swapped.
Bit 0= ‘1’:Upstream Port DP/DM is Swapped

Revision 1.92 (11-28-07) 22 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

4.2.1.21 Register FBh: Port Remap 12

BIT

NUMBER BIT NAME DESCRIPTION

7:0 PRTR12 Port remap register for ports 1 & 2.

When a hub is enumerated by a USB Host Controller, the hub is only
permitted to report how many ports it has; the hub is not permitted to select
a numerical range or assignment. The Host Controller will number the
downstream ports of the hub starting with the number '1', up to the number
of ports that the hub reported having.

The host's port number is referred to as "Logical Port Number" and the
physical port on the hub is the “Physical Port Number". When remapping
mode is enabled (see PRTMAP_EN in Register 08h: Configuration Data
Byte 3) the hub's downstream port numbers can be remapped to different
logical port numbers (assigned by the host).

Note: The OEM must ensure that Contiguous Logical Port Numbers are

used, starting from #1 up to the maximum number of enabled ports;
this ensures that the hub's ports are numbered in accordance with
the way a Host will communicate with the ports.

Table 4.2 Port Remap Register for Ports 1 & 2

Bit [7:4] ‘0000’ Physical Port 2 is Disabled

‘0001’ Physical Port 2 is mapped to Logical Port 1

‘0010’ Physical Port 2 is mapped to Logical Port 2

‘0011’

to

‘1111’

Bit [3:0] ‘0000’ Physical Port 1 is Disabled

‘0001’ Physical Port 1 is mapped to Logical Port 1

‘0010’ Physical Port 1 is mapped to Logical Port 2

‘0011’

to

‘1111’

Illegal; Do Not Use

Illegal; Do Not Use

SMSC USB2512 23 Revision 1.92 (11-28-07)

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

4.2.1.22 Register FFh: Status/Command

BIT

NUMBER BIT NAME DESCRIPTION

7:3 Reserved Reserved

2 INTF_PW_DN SMBus Interface Power Down

‘0’ = Interface is active
‘1’ = Interface power down after ACk has completed

Datasheet

1 RESET Reset the SMBus Interface and internal memory back to RESET_N

0 USB_ATTACH USB Attach (and write protect)

assertion default settings.

‘0’ = Normal Run/Idle State
‘1’ = Force a reset of registers to their default state

‘0’ = SMBus slave interface is active
‘1’ = Hub will signal a USB attach event to an upstream device, and the
internal memory (address range 00h-FEh) is “write-protected” to prevent
unintentional data corruption.

4.2.2 I2C EEPROM

The I2C EEPROM interface implements a subset of the I2C Master Specification (Please refer to the
Philips Semiconductor Standard I2C-Bus Specification for details on I2C bus protocols). The Hub’s I2C
EEPROM interface is designed to attach to a single “dedicated” I2C EEPROM, and it conforms to the
Standard-mode I2C Specification (100kbit/s transfer rate and 7-bit addressing) for protocol and
electrical compatibility.

Note: Extensions to the I2C Specification are not supported.

The Hub acts as the master and generates the serial clock SCL, controls the bus access (determines
which device acts as the transmitter and which device acts as the receiver), and generates the START
and STOP conditions.

4.2.2.1 Implementation Characteristics

The Hub will only access an EEPROM using the Sequential Read Protocol.

4.2.2.2 Pull-Up Resistor

The Circuit board designer is required to place external pull-up resistors (10KΩ recommended) on the
SDA/SMBDATA & SCL/SMBCLK/CFG_SELO lines (per SMBus 1.0 Specification, and EEPROM
manufacturer guidelines) to Vcc in order to assure proper operation.

4.2.2.3 I2C EEPROM Slave Address

Slave address is 1010000.

Note: 10-bit addressing is NOT supported.

Revision 1.92 (11-28-07) 24 SMSC USB2512

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

4.2.3 In-Circuit EEPROM Programming

The EEPROM can be programmed via ATE by pulling RESET_N low (which tri-states the Hub’s
EEPROM interface and allows an external source to program the EEPROM).

4.3 SMBus Slave Interface

Instead of loading User-Defined Descriptor data from an external EEPROM, the SMSC Hub can be
configured to receive a code load from an external processor via an SMBus interface. The SMBus
interface shares the same pins as the EEPROM interface; if CFG_SEL1 & CFG_SEL0 activates the
SMBus interface, external EEPROM support is no longer available (and the user-defined descriptor
data must be downloaded via the SMBus). Due to system issues, the SMSC Hub waits indefinitely for
the SMBus code load to complete and only “appears” as a newly connected device on USB after the
code load is complete.

The Hub’s SMBus implementation is a subset of the SMBus interface to the host. The device is a
slave-only SMBus device. The implementation in the device is a subset of SMBus since it only supports
two protocols.

The Write Block and Read Block protocols are the only valid SMBus protocols for the Hub. The Hub
responds to other protocols as described in Section 4.3.2, "Invalid Protocol Response Behavior," on

page 26. Reference the System Management Bus Specification, Rev 1.0.

The SMBus interface is used to read and write the registers in the device. The register set is shown
in Section 4.2.1, "Internal Register Set (Common to EEPROM and SMBus)," on page 13.

4.3.1 Bus Protocols

Typical Write Block and Read Block protocols are shown below. Register accesses are performed
using 7-bit slave addressing, an 8-bit register address field, and an 8-bit data field. The shading
indicates the Hub driving data on the SMBDATA line; otherwise, host data is on the SDA/SMBDATA
line.

The slave address is the unique SMBus Interface Address for the Hub that identifies it on SMBus. The
register address field is the internal address of the register to be accessed. The register data field is
the data that the host is attempting to write to the register or the contents of the register that the host
is attempting to read.

Note: Data bytes are transferred MSB first (msb first).

4.3.1.1 Block Read/Write

The Block Write begins with a slave address and a write condition. After the command code, the host
issues a byte count which describes how many more bytes will follow in the message. If a slave had
20 bytes to send, the first byte would be the number 20 (14h), followed by the 20 bytes of data. The
byte count may not be 0. A Block Read or Write is allowed to transfer a maximum of 32 data bytes.

Note: For the following SMBus tables:

Denotes Master-to-Slave Denotes Slave-to-Master

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17118A1

S Slave Address Register AddressWr A

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

...

81 1 188

Byte Count = N

A Data byte 1 A Data byte 2

Block Write

Figure 4.1 Block Write

Block Read

A Block Read differs from a block write in that the repeated start condition exists to satisfy the I2C
specification’s requirement for a change in the transfer direction.

17118

81 1 188

Byte Count = N

Data byte 1 Data byte 2 Data byte N

Block Read

Figure 4.2 Block Read

181

A

1

1

SS Slave Address Register AddressWr A

A

A AAA

Data byte N A P

711

Slave Address Rd A

181

...

P

4.3.2 Invalid Protocol Response Behavior

Registers that are accessed with an invalid protocol are not updated. A register is only updated
following a valid protocol. The only valid protocols are Write Block and Read Block, which are
described above.

The Hub only responds to the hardware selected Slave Address.

Attempting to communicate with the Hub over SMBus with an invalid slave address or invalid protocol
results in no response, and the SMBus Slave Interface returns to the idle state.

The only valid registers that are accessible by the SMBus slave address are the registers defined in
the Registers Section. See Section 4.3.3 for the response to undefined registers.

4.3.3 General Call Address Response

The Hub does not respond to a general call address of 0000_000b.

4.3.4 Slave Device Time-Out

According to the SMBus Specification, V1.0 devices in a transfer can abort the transfer in progress
and release the bus when any single clock low interval exceeds 25ms (T
have detected this condition must reset their communication and be able to receive a new START
condition no later than 35ms (T

Note: Some simple devices do not contain a clock low drive circuit; this simple kind of device typically

resets its communications port after a start or stop condition. The Slave Device Time-Out must
be implemented.

TIMEOUT, MAX

).

TIMEOUT, MIN

). Devices that

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4.3.5 Stretching the SCLK Signal

The Hub supports stretching of the SCLK by other devices on the SMBus. The Hub does not stretch
the SCLK.

4.3.6 SMBus Timing

The SMBus Slave Interface complies with the SMBus AC Timing Specification. See the SMBus timing
in the “Timing Diagram” section.

4.3.7 Bus Reset Sequence

The SMBus Slave Interface resets and returns to the idle state upon a START field followed
immediately by a STOP field.

4.3.8 SMBus Alert Response Address

The SMBALERT# signal is not supported by the Hub.

4.3.8.1 Undefined Registers

The registers shown in Ta bl e 4 . 1 are the defined registers in the Hub. Reads to undefined registers
return 00h. Writes to undefined registers have no effect and do not return an error.

4.3.8.2 Reserved Registers

Unless otherwise instructed, only a ‘0’ may be written to all reserved registers or bits.

4.4 Default Configuration Option:

The SMSC Hub can be configured via its internal default configuration. (please see Section 4.2.1,

"Internal Register Set (Common to EEPROM and SMBus)" for specific details on how to enable default

configuration.)

Please refer to Ta bl e 4 .1 for the internal default values that are loaded when this option is selected.

4.5 Default Strapping Options:

The USB2512 can be configured via a combination of internal default values and pin strap options.
Please see Tab le 3 .1 and Tab le 3. 2 for specific details on how to enable the default/pin-strap
configuration option.

The strapping option pins only cover a limited sub-set of the configuration options. The internal default
values will be used for the bits & registers that are not controlled by a strapping option pin. Please
refer to Table 4.1 for the internal default values that are loaded when this option is selected.

4.6 Reset

There are two different resets that the Hub experiences. One is a hardware reset (either from the
internal POR reset circuit or via the RESET_N pin) and the second is a USB Bus Reset.

4.6.1 Internal POR Hardware Reset

All reset timing parameters are guaranteed by design.

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4.6.2 External Hardware RESET_N

A valid hardware reset is defined as assertion of RESET_N for a minimum of 1us after all power
supplies are within operating range. While reset is asserted, the Hub (and its associated external
circuitry) consumes less than 500μA of current from the upstream USB power source.

Assertion of RESET_N (external pin) causes the following:

1. All downstream ports are disabled, and PRTPWR power to downstream devices is removed.

2. The PHYs are disabled, and the differential pairs will be in a high-impedance state.

3. All transactions immediately terminate; no states are saved.

4. All internal registers return to the default state (in most cases, 00(h)).

5. The external crystal oscillator is halted.

6. The PLL is halted.

The Hub is “operational” 500μs after RESET_N is negated.

Once operational, the Hub immediately reads OEM-specific data from the external EEPROM (if the
SMBus option is not disabled).

4.6.2.1 RESET_N for Strapping Option Configuration

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Hardware

reset

asserted

Read Strap

Options

t1

Drive Strap

Outputs to

inactive

levels

Attach

USB

Upstream

t5 t6

USB Reset

recovery

Idle

t7 t8

Start

completion

request

response

t2

Valid

t3

t4

Don’t Care

Driven by Hub if strap is an output.

RESET_N

VSS

Strap Pins

Don’t Care

VSS

Figure 4.3 Reset_N Timing for Default/Strap Option Mode

Table 4.3 Reset_N Timing for Default/Strap Option Mode

NAME DESCRIPTION MIN TYP MAX UNITS

t1 RESET_N Asserted. 1 μsec

t2 Strap Setup Time 16.7 nsec

t3 Strap Hold Time. 16.7 1400 nsec

t4 hub outputs driven to inactive logic states 1.5 2 μsec

t5 USB Attach (See Note). 100 msec

t6 Host acknowledges attach and signals USB

100 msec

Reset.

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Table 4.3 Reset_N Timing for Default/Strap Option Mode (continued)

NAME DESCRIPTION MIN TYP MAX UNITS

t7 USB Idle. undefined msec

t8 Completion time for requests (with or without data

stage).

Notes:

 When in Bus-Powered mode, the Hub and its associated circuitry must not consume more than

100mA from the upstream USB power source during t1+t5.

 All Power Supplies must have reached the operating levels mandated in Chapter 5, DC

Parameters, prior to (or coincident with) the assertion of RESET_N.

4.6.2.2 RESET_N for EEPROM Configuration

Hardware

reset

asserted

Read Strap

Options

Read EEPROM

+

Set Options

t4

RESET_N

VSS

t1

t2

t3

Attach

USB

Upstream

USB Reset

recovery

Idle

t5 t6 t7

5 msec

Start

completion

request

response

Figure 4.4 Reset_N Timing for EEPROM Mode

Table 4.4 Reset_N Timing for EEPROM Mode

NAME DESCRIPTION MIN TYP MAX UNITS

t1 RESET_N Asserted. 1 μsec

t2 Hub Recovery/Stabilization. 500 μsec

t3 EEPROM Read / Hub Config. 2.0 99.5 msec

t4 USB Attach (See Note). 100 msec

t5 Host acknowledges attach and signals USB

100 msec

Reset.

t6 USB Idle. undefined msec

t7 Completion time for requests (with or without data

5 msec

stage).

Notes:

 When in Bus-Powered mode, the Hub and its associated circuitry must not consume more than

100mA from the upstream USB power source during t4+t5+t6+t7.

 All Power Supplies must have reached the operating levels mandated in Chapter 5, DC

Parameters, prior to (or coincident with) the assertion of RESET_N.

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4.6.2.3 RESET_N for SMBus Slave Configuration

USB 2.0 High-Speed 2-Port Hub Controller

Datasheet

Hardware

RESET_N

VSS

reset

asserted

Reset

Negation

t1

SMBus Code

Load

t2 t4

Hub PHY

Stabilization

t3

Attach

USB

Upstream

USB Reset

recovery

t5

Idle

t6 t7

Start

completion

request

response

Figure 4.5 Reset_N Timing for SMBus Mode

Table 4.5 Reset_N Timing for SMBus Mode

NAME DESCRIPTION MIN TYP MAX UNITS

t1 RESET_N Asserted. 1 μsec

t2 Hub Recovery/Stabilization. 500 μsec

t3 SMBus Code Load (See Note). 250 300 msec

t4 Hub Configuration and USB Attach. 100 msec

t5 Host acknowledges attach and signals USB

100 msec

Reset.

t6 USB Idle. Undefined msec

t7 Completion time for requests (with or without data

5 msec

stage).

Notes:

 For Bus-Powered configurations, the 99.5ms (MAX) is required, and the Hub and its associated

circuitry must not consume more than 100mA from the upstream USB power source during
t2+t3+t4+t5+t6+t7. For Self-Powered configurations, t3 MAX is not applicable and the time to load
the configuration is determined by the external SMBus host.

 All Power Supplies must have reached the operating levels mandated in Chapter 5, DC

Parameters, prior to (or coincident with) the assertion of RESET_N.

4.6.3 USB Bus Reset

In response to the upstream port signaling a reset to the Hub, the Hub does the following:

Note: The Hub does not propagate the upstream USB reset to downstream devices.

1. Sets default address to 0.

2. Sets configuration to: Unconfigured.

3. Negates PRTPWR[2:1] to all downstream ports.

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4. Clears all TT buffers.

5. Moves device from suspended to active (if suspended).

6. Complies with Section 11.10 of the USB 2.0 Specification for behavior after completion of the reset
sequence.

The Host then configures the Hub and the Hub’s downstream port devices in accordance with the USB
Specification.

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Chapter 5 DC Parameters

5.1 Maximum Guaranteed Ratings

PARAMETER SYMBOL MIN MAX UNITS COMMENTS

Storage

Temperature

Lead

Temperature

1.8V supply
voltage

3.3V supply
voltage

Voltage on any

I/O pin

Voltage on

XTAL1

Voltage on

XTAL2

T

A

-55 150 °C

325 °C Soldering < 10 seconds

V

DDA18PLL,

V

DD18

V

DDA33,

V

DD33PLL,

V

DD33,

V

DD33CR

2.5 V

4.6 V

-0.5 5.5 V

-0.5 4.0 V

-0.5 3.6 V

Note: Stresses above the specified parameters could cause permanent damage to the device. This

is a stress rating only and functional operation of the device at any condition above those
indicated in the operation sections of this specification is not implied. When powering this
device from laboratory or system power supplies, it is important that the Absolute Maximum
Ratings not be exceeded or device failure can result. Some power supplies exhibit voltage
spikes on their outputs when the AC power is switched on or off. In addition, voltage transients
on the AC power line may appear on the DC output. When this possibility exists, it is suggested
that a clamp circuit be used.

5.2 Recommended Operating Conditions

PARAMETER SYMBOL MIN MAX UNITS COMMENTS

Operating

Temperature

1.8V supply voltage V

3.3V supply voltage V

Voltage on any I/O pin -0.3 5.5 V If any 3.3V supply voltage drops

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T

A

DDA18PLL

V

DD18

DDA33

V

DDA33PLL

V

DD33

V

DD33CR

070°C

1.62 1.98 V

3.0 3.6 V

below 3.0V, then the MAX
becomes:

(3.3V supply voltage) + 0.5

DATASHEET

USB 2.0 High-Speed 2-Port Hub Controller

PARAMETER SYMBOL MIN MAX UNITS COMMENTS

Datasheet

Voltage on XTAL1 -0.3 V

Voltage on XTAL2 -0.3 V

DDA33

DD18

V

V

Table 5.1 DC Electrical Characteristics

PARAMETER SYMBOL MIN TYP MAX UNITS COMMENTS

I, IS Type Input Buffer

Low Input Level

High Input Level

Input Leakage

Hysteresis (‘IS’ Only)

V

V

ILI

V

IHI

I

IL

HYSI

2.0

-10

250

0.8

+10

350

V

V

uA

mV

TTL Levels

VIN = 0 to V

Input Buffer with Pull-Up
(IPU)

Low Input Level

High Input Level

Low Input Leakage

High Input Leakage

V

V

I

I

IHI

ILL

IHL

ILI

0.8

2.0

+35

-10

+90

+10

V

V

uA

uA

TTL Levels

VIN = 0

VIN = V

Input Buffer with Pull­Down (IPD)

DD33

DD33

Low Input Level

High Input Level

Low Input Leakage

High Input Leakage

ICLK Input Buffer

Low Input Level

High Input Level

Input Leakage

O12, I/O12 &I/OSD12
Type Buffer

Low Output Level

High Output Level

Output Leakage

Hysteresis (‘SD’ pad only)

IO-U

(Note 2)

V

V

V

V

V

V

ILI

V

IHI

I

ILL

I

IHL

ILCK

IHCK

I

IL

OL

OH

I

OL

HYSC

2.0

+10

-35

1.4

-10

2.4

-10

250

0.8

-10

-90

0.5

+10

0.4

+10

350

V

V

uA

uA

V

V

uA

V

V

uA

mV

TTL Levels

VIN = 0

VIN = V

V

= 0 to V

IN

DD33

DD33

IOL = 12mA @ V

IOH = -12mA @ V

V

= 0 to V

IN

(Note 1)

DD33

DD33

DD33

= 3.3V

= 3.3V

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Table 5.1 DC Electrical Characteristics (continued)

PARAMETER SYMBOL MIN TYP MAX UNITS COMMENTS

Supply Current
Unconfigured

High-Speed Host
Full-Speed Host

Supply Current
Configured
(High-Speed Host)

1 Port HS, 1 Port LS/FS
2 Ports @ LS/FS
2 Ports @ HS

Supply Current
Configured
(Full-Speed Host)

1 Port
2 Ports

Supply Current
Suspend

Supply Current
Reset

Notes:

1. Output leakage is measured with the current pins in high impedance.

2. See USB 2.0 Specification for USB DC electrical characteristics.

I

CCINTHS

I

CCINITFS

I

HCH1C1

I

HCC2

I

HCH2

I

FCC1

I

FCC2

I

CSBY

I

CRST

90
80

95
85

mA
mA

All supplies combined

130
120
135

145
140
200

mA
mA
mA

All supplies combined

105
105

125
125

mA
mA

310 420 μA All supplies combined

105 250 μA All supplies combined

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CAPACITANCE TA = 25°C; fc = 1MHz; V

DD18

, V

DDPLL

= 1.8V

Table 5.2 Pin Capacitance

LIMITS

PARAMETER SYMBOL MIN TYP MAX UNIT TEST CONDITION

Clock Input
Capacitance

Input Capacitance C

Output Capacitance C

C

XTAL

IN

OUT

2 pF All pins except USB pins (and pins under

test tied to AC ground)

10 pF

20 pF

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Chapter 6 AC Specifications

6.1 Oscillator/Clock

Crystal: Parallel Resonant, Fundamental Mode, 24 MHz ±350ppm.

External Clock: 50% Duty cycle ± 10%, 24 MHz ± 350ppm, Jitter < 100ps rms.

C

1

XTAL1

(C

CB + C

S1 =

XTAL

)

C

2

Note: C

equals total board/trace capacitance.

B

(C1 + CS1) x (C2 + CS2)

(C

Figure 6.2 Formula to find value of C

6.1.1 SMBus Interface:

The SMSC Hub conforms to all voltage, power, and timing characteristics and specifications as set
forth in the SMBus 1.0 Specification for Slave-Only devices (except as noted in Section 4.3).

Crystal

Figure 6.1 Typical Crystal Circuit

+ CS1 + C2 + CS2)

1

C

L

1Meg

C

=

and C

1

XTAL2

(C

S2 =

CB + C

L

2

XTAL

)

6.1.2 I2C EEPROM:

Frequency is fixed at 58.6KHz ± 20%.

6.1.3 USB 2.0

The SMSC Hub conforms to all voltage, power, and timing characteristics and specifications as set
forth in the USB 2.0 Specification. Please refer to the USB 2.0 Specification for more information.

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DATASHEET

Chapter 7 Package Outline

DATASHEET

Figure 7.1 36-Pin QFN, 6x6mm Body, 0.5mm Pitch

SMSC USB2512 37 Revision 1.92 (11-28-07)