SMSC USB4640i User Manual

SMSC USB4640/USB4640i

Revision 1.0 (06-01-09) 

The SMSC USB4640/USB4640i is a Hi-Speed HSIC USB hub

and card reader combo solution with an upstream port

compliant to HSIC 1.0, a supplement to the USB 2.0

specification. The two downstream ports are compliant with the

USB 2.0 specification.

High Speed Inter-Chip (HSIC) is a digital interconnect bus that

enables the use of USB technology as a low-power chip-to-chip

interconnect at speeds up to 480 Mb/s. The HSIC interface is

an industry standard 2-pin digital interface which uses standard

USB software. The SMSC USB4640/USB4640i provides an

ultra fast interface between an HSIC enabled host and today’s

popular flash media formats. The controller allows read/write

capability to flash media from the following families:

– Secure Digital

TM

 (SD)

– MultiMediaCard

TM

 (MMC)

– Memory Stick

® 

(MS)

– xD Picture Card

TM

 (xD)

1

The USB4640/USB4640i offers a versatile, cost-effective, and

energy-efficient hub controller with 2 downstream USB 2.0

ports. This combo solution leverages SMSC’s innovative

technology that delivers industry-leading data throughput in

mixed-speed USB environments. Average sustained transfer

rates exceeding 35 MB/s are possible

2

.

„

Upstream HSIC port and 2 exposed Hi-Speed USB 2.0 

downstream ports for external peripheral expansion

„

The dedicated flash media reader is internally attached to a 

3rd downstream port of the hub as a USB Compound 
Device 

— a single or multiplexed flash media reader interface

„

— Flexible port mapping and port disable sequencing supports 

multiple platform designs

„

— Programmable USB differential-pair pin locations eases PCB 

design by aligning USB signal traces directly to connectors

„

— Programmable USB transceiver drive strength recovers signal 

integrity 

1.For xD-Picture Card

TM

 support, please obtain a user license

from the xD-Picture Card License Office.
2.Host and media dependent.

„

Compliance with the following flash media card 

specifications SD 2.0 / MMC 4.2 / MS 1.43 / MS-Pro 1.02 / 
MS-Pro-HG 1.01 / MS-Duo 1.10 / xD 1.2

„

Low-power digital HSIC interface offers a replacement for 

onboard host and device connection for analog USB bus 
cable

„

HSIC interface enables printers, mobile PCs, ultra-mobile 

PCs, and cell phone products to reduce the total power 
budget while taking full advantage of USB connectivity and 
compatibility with existing USB drivers and software

„

External 1.2 V reference allows upstream and downstream 

HSIC links to use the same voltage reference

„

Supports a single external 3.3 V supply source; internal 

regulators provide 1.8 V internal core voltage for additional 
bill of materials and power savings

„

The transaction translator (TT) in the hub supports operation 

of Full-Speed and Low-Speed peripherals

„

9 K RAM | 64 K on-chip ROM

„

Enhanced EMI rejection and ESD protection performance

„

Hub and flash media reader/writer configuration from a 

single source: External I

2

C

®

 ROM or external SPI ROM

— Configures internal code using an external I

2

C EEPROM

— Supports external code using an SPI Flash EEPROM
— Customizable vendor ID, product ID, and language ID if using 

an external EEPROM

„

Up to 9 configurable GPIOs for special functions

„

The USB4640 supports the commercial temperature range 

of 0°C to +70°C

„

The USB4640i supports the industrial temperature range of 

-40°C to +85°C 

„

48-pin QFN lead-free, RoHS compliant package (7x7 mm)

„

3G/4G handsets, smartphones, cell phones, and other 

mobile devices

„

Desktop and mobile PCs

„

Printers

„

GPS navigation systems

„

Media players/viewers

„

Consumer A/V

„

Set-top boxes

Industrial products