Datasheet
High-Speed Inter-Chip (HSIC) USB 2.0 Hub and Flash Media Controller
Datasheet
Revision 1.3 (03-13-13) 10 SMSC USB4640/USB4640i
DATASHEET
Chapter 2 Block Diagram
Figure 2.1 USB4640/USB4640i Block Diagram
1.2 V
HSIC
HSIC 
Data & Strobe
Repeater
Controller
Serial 
Interface 
Engine
Serial 
Interface
Routing & Port Re-Ordering Logic
Port Controller
PHY
Port #3
OC 
Sense
Switch 
Driver
Transaction
Translator
PHY
Port #2
OC 
Sense
Switch 
Driver
USB Data
Downstream
OC Sense/
Pwr Switch
8051
PROCESSOR
SFR 
RAM
XDATA BRIDGE
+ BUS ARBITER
ROM 
64 K
RAM
6 K
ADDR
MAP
GPIOs
Program Memory I/O Bus
PWR_FET0
8 pins
GPIO10 (CRD_PWR)
GPIO
3 K
total
RAM
EP2 TX
EP2 RX
BUS 
INTFC
EP2 RX
EP0 TX
EP0 RX
SIE
CTL
BRIDGE
BUS 
INTFC
FMDU
CTL
AUTO_CBW 
PROC
FMI
BUS 
INTFC
USB Data
Downstream
Flash Media Cards 
(require Combo socket)
MS
xD*
SD/
MMC/
SDIO
OC Sense/
Pwr Switch
SPI
SPI (4 pins) 
3.3 V
1.8 V
PLL
24 MHz 
Crystal
1.8 V Reg
*For xD-Picture Card
TM 
support, please obtain a user 
license from the xD-Picture Card License office.
3.3 V
1.8 V Reg
VDDCR
HSIC 
Impedance










