– Compatible with Hot-Plug I/O expanders used on PC and
server motherboards
Power Management
– Utilizes advanced low-power design techniques to achieve low
typical power consumption
– Supports PCI Power Management Interface specification (PCI-
PM 1.1)
• Supports device power management states: D0, D3
hot
and
D3
cold
– Unused SerDes are disabled
Block Diagram
7-Port Switch Core / 16 PCI Express Lanes
Frame Buffer
Route Table
Port
Arbitration
Scheduler
Transaction Layer
Data Link Layer
Transaction Layer
Data Link Layer
Transaction Layer
Data Link Layer
TL
DLL
Mux/Demux
Phy
Logical
Layer
TL
DLL
Mux/Demux
Phy
Logical
Layer
Multiplexer / Demultiplexer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
Multiplexer / Demultiplexer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
Multiplexer / Demultiplexer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
Phy
Logical
Layer
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
SerDes
(Port 0)
(Port 1)
(Port 6)
Figure 1 Internal Block Diagram
(Port 2)
(Port 5)
IDT and the IDT logo are registered trademarks of Integrated Device Technology, Inc.
1 of 33
March 25, 2008
IDT 89HPES16T7 Data Sheet
Testability and Debug Features
– Ability to read and write any internal register via the SMBus
Twelve General Purpose Input/Output pins
– Each pin may be individually configured as an input or output
– Each pin may be individually configured as an interrupt input
– Some pins have selectable alternate functions
Packaged in a 25mm x 25mm 320-ball BGA with 1 mm ball spacing
Product Description
Utilizing standard PCI Express interconnect, the PES16T7 provides the most efficient I/O connectivity solution for applications requiring high
throughput, low latency, and simple board layout with a minimum number of board layers. It provides connectivity for up to 7 ports across 16 integrated
serial lanes. Each lane provides 2.5 Gbps of bandwidth in both directions and is fully compliant with PCI Express Base specification revision 1.1.
The PES16T7 is based on a flexible and efficient layered architecture. The PCI Express layer consists of SerDes, Physical, Data Link and Trans-
action layers. The PES16T7 can operate either as a store and forward switch or a cut-through switch and is designed to switch memory and I/O trans-
actions. It supports eight Traffic Classes (TCs) and one Virtual Channel (VC) with sophisticated resource management to allow efficient switching for
applications requiring additional narrow port connectivity and also some high-end connectivity.
Processor
Processor
North
Bridge
Memory
Memory
Memory
Memory
South
Bridge
x4
PES16T7
x4
x4
x1
I/O
x1
I/O
x1
I/O
SATA
x1
I/O
SATA
PCI Express
Slots
Figure 2 I/O Expansion Application
x8 Upstream
x8
x4 Upstream
x4
PES16T7
PES16T7
x4
x1
x1
x1
x1
x4
x4
x1
x1
x1
x1
Figure 3 Configuration Options
2 of 33
March 25, 2008
IDT 89HPES16T7 Data Sheet
SMBus Interface
The PES16T7 contains two SMBus interfaces. The slave interface provides full access to the configuration registers in the PES16T7, allowing
every configuration register in the device to be read or written by an external agent. The master interface allows the default configuration register
values of the PES16T7 to be overridden following a reset with values programmed in an external serial EEPROM. The master interface is also used
by an external Hot-Plug I/O expander.
Six pins make up each of the two SMBus interfaces. These pins consist of an SMBus clock pin, an SMBus data pin, and 4 SMBus address pins. In
the slave interface, these address pins allow the SMBus address to which the device responds to be configured. In the master interface, these
address pins allow the SMBus address of the serial configuration EEPROM from which data is loaded to be configured. The SMBus address is set up
on negation of PERSTN by sampling the corresponding address pins. When the pins are sampled, the resulting address is assigned as shown in
Table 1.
Bit
1
2
3
4
5
6
7
Slave
SMBus
Address
SSMBADDR[1]
SSMBADDR[2]
SSMBADDR[3]
0
SSMBADDR[5]
1
1
Master
SMBus
Address
MSMBADDR[1]
MSMBADDR[2]
MSMBADDR[3]
MSMBADDR[4]
1
0
1
Table 1 Master and Slave SMBus Address Assignment
As shown in Figure 4, the master and slave SMBuses may be used in a unified or split configuration. In the unified configuration, shown in Figure
4(a), the master and slave SMBuses are tied together and the PES16T7 acts both as a SMBus master as well as a SMBus slave on this bus. This
requires that the SMBus master or processor that has access to PES16T7 registers supports SMBus arbitration. In some systems, this SMBus master
interface may be implemented using general purpose I/O pins on a processor or micro controller, and may not support SMBus arbitration. To support
these systems, the PES16T7 may be configured to operate in a split configuration as shown in Figure 4(b).
In the split configuration, the master and slave SMBuses operate as two independent buses and thus multi-master arbitration is never required.
The PES16T7 supports reading and writing of the serial EEPROM on the master SMBus via the slave SMBus, allowing in system programming of the
serial EEPROM.
PES16T7
Processor
SMBus
Master
Serial
EEPROM
...
Other
SMBus
Devices
PES16T7
Processor
SMBus
Master
...
Other
SMBus
Devices
SSMBCLK
SSMBDAT
MSMBCLK
MSMBDAT
SSMBCLK
SSMBDAT
MSMBCLK
MSMBDAT
Serial
EEPROM
(a) Unified Configuration and Management Bus
(b) Split Configuration and Management Buses
Figure 4 SMBus Interface Configuration Examples
3 of 33
March 25, 2008
IDT 89HPES16T7 Data Sheet
Hot-Plug Interface
The PES16T7 supports PCI Express Hot-Plug on each downstream port. To reduce the number of pins required on the device, the PES16T7
utilizes an external I/O expander, such as that used on PC motherboards, connected to the SMBus master interface. Following reset and configura-
tion, whenever the state of a Hot-Plug output needs to be modified, the PES16T7 generates an SMBus transaction to the I/O expander with the new
value of all of the outputs. Whenever a Hot-Plug input changes, the I/O expander generates an interrupt which is received on the IOEXPINTN input pin
(alternate function of GPIO) of the PES16T7. In response to an I/O expander interrupt, the PES16T7 generates an SMBus transaction to read the
state of all of the Hot-Plug inputs from the I/O expander.
General Purpose Input/Output
The PES16T7 provides 12 General Purpose Input/Output (GPIO) pins that may be used by the system designer as bit I/O ports. Each GPIO pin
may be configured independently as an input or output through software control. Some GPIO pins are shared with other on-chip functions. These
alternate functions may be enabled via software, SMBus slave interface, or serial configuration EEPROM.
Pin Description
The following tables lists the functions of the pins provided on the PES16T7. Some of the functions listed may be multiplexed onto the same pin.
The active polarity of a signal is defined using a suffix. Signals ending with an “N” are defined as being active, or asserted, when at a logic zero (low)
level. All other signals (including clocks, buses, and select lines) will be interpreted as being active, or asserted, when at a logic one (high) level.
Signal
PE0RP[3:0]
PE0RN[3:0]
PE0TP[3:0]
PE0TN[3:0]
PE1RP[3:0]
PE1RN[3:0]
PE1TP[3:0]
PE1TN[3:0]
PE2RP[0]
PE2RN[0]
PE2TP[0]
PE2TN[0]
PE3RP[0]
PE3RN[0]
PE3TP[0]
PE3TN[0]
PE4RP[0]
PE4RN[0]
PE4TP[0]
PE4TN[0]
PE5RP[0]
PE5RN[0]
PE5TP[0]
PE5TN[0]
PE6RP[3:0]
PE6RN[3:0]
Type
I
O
I
O
I
O
I
O
I
O
I
O
I
Name/Description
PCI Express Port 0 Serial Data Receive.
Differential PCI Express receive
pairs for port 0.
PCI Express Port 0 Serial Data Transmit.
Differential PCI Express trans-
mit pairs for port 0.
PCI Express Port 1 Serial Data Receive.
Differential PCI Express receive
pairs for port 1.
PCI Express Port 1 Serial Data Transmit.
Differential PCI Express trans-
mit pairs for port 1.
PCI Express Port 2 Serial Data Receive.
Differential PCI Express receive
pairs for port 2.
PCI Express Port 2 Serial Data Transmit.
Differential PCI Express trans-
mit pairs for port 2.
PCI Express Port 3 Serial Data Receive.
Differential PCI Express receive
pair for port 3.
PCI Express Port 3 Serial Data Transmit.
Differential PCI Express trans-
mit pair for port 3.
PCI Express Port 4 Serial Data Receive.
Differential PCI Express receive
pair for port 4.
PCI Express Port 4 Serial Data Transmit.
Differential PCI Express trans-
mit pair for port 4.
PCI Express Port 5 Serial Data Receive.
Differential PCI Express receive
pair for port 5.
PCI Express Port 5 Serial Data Transmit.
Differential PCI Express trans-
mit pair for port 5.
PCI Express Port 6 Serial Data Receive.
Differential PCI Express receive
pair for port 6.
Table 2 PCI Express Interface Pins (Part 1 of 2)
4 of 33
March 25, 2008
IDT 89HPES16T7 Data Sheet
Signal
PE6TP[3:0]
PE6TN[3:0]
PEREFCLKP[2:1]
PEREFCLKN[2:1]
Type
O
I
Name/Description
PCI Express Port 6 Serial Data Transmit.
Differential PCI Express trans-
mit pair for port 6.
PCI Express Reference Clock.
Differential reference clock pair input. This
clock is used as the reference clock by on-chip PLLs to generate the clocks
required for the system logic and on-chip SerDes. The frequency of the dif-
ferential reference clock is determined by the REFCLKM signal.
PCI Express Reference Clock Mode Select.
This signal selects the fre-
quency of the reference clock input.
0x0 - 100 MHz
0x1 - 125 MHz
Table 2 PCI Express Interface Pins (Part 2 of 2)
REFCLKM
I
Signal
MSMBADDR[4:1]
MSMBCLK
Type
I
I/O
Name/Description
Master SMBus Address.
These pins determine the SMBus address of the
serial EEPROM from which configuration information is loaded.
Master SMBus Clock.
This bidirectional signal is used to synchronize
transfers on the master SMBus. It is active and generating the clock only
when the EEPROM or I/O Expanders are being accessed.
Master SMBus Data.
This bidirectional signal is used for data on the mas-
ter SMBus.
Slave SMBus Address.
These pins determine the SMBus address to
which the slave SMBus interface responds.
Slave SMBus Clock.
This bidirectional signal is used to synchronize trans-
fers on the slave SMBus.
Slave SMBus Data.
This bidirectional signal is used for data on the slave
SMBus.
Table 3 SMBus Interface Pins
MSMBDAT
SSMBADDR[5,3:1]
SSMBCLK
SSMBDAT
I/O
I
I/O
I/O
Signal
GPIO[0]
Type
I/O
Name/Description
General Purpose I/O.
This pin can be configured as a general purpose I/O pin.
Alternate function pin name: P2RSTN
Alternate function pin type: Output
Alternate function: Reset output for downstream port 2
General Purpose I/O.
This pin can be configured as a general purpose I/O pin.
Alternate function pin name: P4RSTN
Alternate function pin type: Output
Alternate function: Reset output for downstream port 4
General Purpose I/O.
This pin can be configured as a general purpose I/O pin.