SMSC USB2524 Manual De Usuario

SMSC USB2524

Revision 1.91 (08-22-07) 

 

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USB 2.0 Compatible 4-Port Hub with two upstream 

host port connections

—

Provides electronic reconfiguration and re-assignment 
of any of its 4 downstream ports to either of two 
upstream host ports (“on-the-fly”).

—

Allows multiple USB hosts to share peripherals and 
enables a user to dynamically assign host ownership.

– Embedded Mode - 8 (predefined, OEM 

programmable) configurations for port 
assignment are selectable via three external 
control signals. 

– Peripheral Mode - Dedicated select pin for 

every downstream port (total of 4), selectable 
edge or level triggered in order to support a 
wide range of possible switch configurations 
and styles.

—

Each host has a dedicated Single Transaction 
Translator (Single-TT) for supporting FS/LS devices, or 
can also operate in Multi-TT mode where each 
downstream port has a dedicated Transaction 
Translator.

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Downstream ports can be disabled or defined as non-

removable

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Switching hub can be configured as compound 

device for support of ‘embedded’ USB peripherals

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Multiple LED modes for maximum implementation 

flexibility

—

USB Mode - 2 Single-color LEDs for each downstream 
port (total of 8 LEDs).

—

Host Ownership Mode - 8 Single-Color LEDs indicate 
which upstream host each of the downstream ports are 
assigned to.

—

Host Ownership & Port Speed Mode - 8 Dual-Color 
LEDs are used to indicate which upstream host each of 
the downstream ports are assigned to, while 
simultaneously indicating downstream port connection 
speed.

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Enhanced configuration options available through 

either a Single Serial I

2

C EEPROM, or SMBus Slave 

Port
— VID/PID/DID 
— Port Configuration

—

String Descriptors (each can support a maximum length 
of 31 characters)

– Custom Manufacturer String
– Custom Product String
– Custom Serial String

—

Assignment of downstream ports to upstream hosts

—

Switching mechanism selection

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Hardware Strapping options allow for configuration 

without an external EEPROM or SMBus Host

—

Default VID/PID/DID, allows functionality when 
configuration EEPROM is absent

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Complete USB Specification 2.0 Compatibility

—

Includes USB 2.0 Hi-Speed Transceivers

—

High-Speed (480Mbits/s), Full-Speed (12Mbits/s) and 
Low-Speed (1.5Mbits/s) compatible

—

Full power management with choice of Individual or 
Ganged power control

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On-Board 24MHz Crystal Driver Circuit or 24 MHz 

external clock driver

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Internal PLL for 480MHz USB 2.0 Sampling 

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Internal 1.8V Linear Voltage Regulator

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Integrated USB termination and Pull-up/Pull-down 

resistors

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Internal Short Circuit protection of USB differential 

signal pins

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1.8 Volt Low Power Core Operation

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3.3 Volt I/O with 5V Input Tolerance

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56-Pin QFN Lead-free RoHS Compliant Package