Datasheet
Hi-Speed USB Host, Device or OTG PHY with ULPI Low Pin Interface
Datasheet
Revision 1.1 (01-24-13) 22 SMSC USB3300
DATASHEET
6.1.1 Overview
Figure 6.2 illustrates the block diagram of the ULPI digital functions. It should be noted that this PHY
does not use a “ULPI wrapper” around a UTMI+ PHY core as the ULPI specification implies.
The advantage of a “wrapper less” architecture is that the PHY has a lower USB latency than a design
which must first register signals into the PHY’s wrapper before the transfer to the PHY core. A low
latency PHY allows a Link to use a wrapper around a UTMI Link and still make the required USB turn-
around timing given in the USB 2.0 specification.
RxEndDelay maximum allowed by the UTMI+/ULPI for 8-bit data is 63 high speed clocks. USB3300
uses a low latency high speed receiver path to lower the RxEndDelay to 43 high speed clocks. This
low latency design gives the Link more cycles to make decisions and reduces the Link complexity. This
is the result of the “wrapper less” architecture of the USB3300. This low RxEndDelay should allow
legacy UTMI Links to use a “wrapper” to convert the UTMI+ interface to a ULPI interface.
Figure 6.2 ULPI Digital Block Diagram
Data[7:0]
Interrupt
Control
High Speed TX
Full Speed TX
Low Speed TX
High Speed Data
Recovery
Full / Low Speed
Data Recovery
ULPI Protocol
Block
6pinSerial Mode
XcvrSelect[1:0]
TermSelect
OpMode[1:0]
Reset
SuspendM
3pinSerial Mode
ClockSuspendM
AutoResume
Indicator Complement
Indicator Pass Thru
Interface Protect Disable
IdPullUp
DpPulldown
DmPulldown
DischrgVbus
ChrgVbus
DrvVbus
DrvVbusExternal
UseExternal Vbus Indicator
InterruptEnable Rise[4:0]
InterruptEnableFall[4:0]
InterruptStatus[4:0]
InterruptLatch[4:0]
Linestates[1:0]
VbusValid
SessionValid
SessionEnd
HS Tx Data
FS/LS Tx Data
HS RX Data
FS/LS Data
NOTE:
The USB3300 uses
a wrapperless ULPI
interface.
DIR
NXT
STP
Tx Data
Rx Data
POR
ULPI Register
Array
HostDisconnect
IdGnd
To OTG
Module
Transceiver
Control
Module
To USB
Transceiver
From OTG
Module
To USB
Transceiver
RXD CMD
From USB
Transceiver