Datasheet
Highly Integrated Full Featured Hi-Speed USB 2.0 ULPI Transceiver
Datasheet
Revision 1.0 (07-14-09) 42 SMSC USB3320
DATASHEET
Chapter 6 ULPI Operation
6.1 Overview
The USB3320 uses the industry standard ULPI digital interface to facilitate communication between
the USB Transceiver (PHY) and Link (device controller). The ULPI interface is designed to reduce the
number of pins required to connect a discrete USB Transceiver to an ASIC or digital controller. For
example, a full UTMI+ Level 3 OTG interface requires 54 signals while a ULPI interface requires only
12 signals.
The ULPI interface is documented completely in the “UTMI+ Low Pin Interface (ULPI) Specification
Revision 1.1”. The following sections describe the operating modes of the USB3320 digital interface.
Figure 6.1 illustrates the block diagram of the ULPI digital functions. It should be noted that this
USB3320 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 USB3320 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
Figure 6.1 ULPI Digital Block Diagram
NOTE:
The ULPI interface
is a wrapperless
design.
POR
ULPI Register Array
Interrupt Control
6pinSerial Mode
XcvrSelect[1:0]
TermSelect
OpMode[1:0]
Reset
SuspendM
3pinSerial Mode
ClockSuspendM
AutoResume
DischrgVbus
ChrgVbus
IdGndDrv
SpkLeftEn
SpkRightEn/MicEn
DpPulldown
DmPulldown
SwapDP/DM
CarkitMode
RegOutput[1:0]
ChargerPullupEnDP
ChargerPullupEnDM
TxdEn
RxdEn
Indicator Complement
Indicator Pass Thru
UseExternal Vbus Indicator
IdPullUp
Linestates[1:0]
HostDisconnect
Interface Protect Disable
VbusValid
SessionValid
SessionEnd
IdGnd
IdFloat
RidCon...Start
RidValue[2:0]
RidCon...Done
Data[7:0]
High Speed TX
Full Speed TX
Low Speed TX
High Speed Data
Recovery
Full / Low Speed
Data Recovery
ULPI Protocol
Block
HS Tx Data
FS/LS Tx Data
HS RX Data
FS/LS Data
DIR
NXT
STP
Tx Data
Rx Data
USB Transmit and Receive Logic
ULPI Register Access
RESETB
ULPI Interupt
Rid State
Machi ne
To RX
Analog
To TX
Analog
Transceiver Control
To
OTG
Analog
To USB
Audio
Analog