4-Pin ATX
Peripheral Power
Connector
J1-J4, J7-J8
U2
5V to 1V
adj. DC/DC
converter
on/off#
U3
5V to 1V
adj. DC/DC
converter
on/off#
U4
5V to
3.3VCC
DC/DC
converter
On board
3.3V Circuits
Dipswitch SW15 is
used to select on
board power source or
external power inputs
to the Sirius chips
BJ4
BJ3
BJ5
BJ6
BJ8
1.0VCC
2.5VCC
GND
GND
24-Pin ATX Main
Power Connector
J9
15 PCI Express Connectors
BJ10
BJ9
1.0VCC_A
SLOT 1
5V
2.5V_A
PEX 8619
12V
12V_A
5V_A
12V_A3
3.3VCC1
U5
5V to 2.5V
adj. DC/DC
converter
R
on/off#
0
5V_A
3.
3VCC
3.3VCC
GND
GND
GND
12V_A1
0
GND
8-Pin ATX +12V
Power Connector
J10
12V_A2
0
SLOT 2
SLOT 3
SLOT 4
SLOT 9
SLOT 10
SLOT 11
SLOT 12
SLOT 5
SLOT 6
SLOT 7
SLOT 8
SLOT 13
SLOT 14
SLOT 15
MOSFET
MOSFET
Serial HP Controller
U117
Dual output
step down
regulator
1.2V
2.5V
Figure 12. RDK Power Distribution Circuits
Refer to
, 15 PCI Express slots including the Serial Hot-Plug controlled SLOT 8
get 3.3 volt and 12 volt
power from 24-pin ATX Main Power Connector, 4-pin ATX Peripheral Power Connectors and the +12V Power
Connector. The RDK on board circuits and the PEX 8619 get their power from the +5V input from the ATX power
supply. DC/DC converter U4 uses 5V input generates 3.3VCC1 to the on board circuit. The 3.3VCC1 further steps
down by voltage regulator U117 to generate 2.5V and 1.2V for Xilinx FPGA (U115).
Three dc/dc converters U2,
U3 and U5 use 5V input to generate 1.0VCC, 1.0VCC_A and 2.5VCC for PEX 8619. Dip switch SW15 can be set
to turn off these dc/dc converters for external power margin tests for PLX use only.
3.9
FPGA Interface
The RDK contains a Xilinx Spartan-3 FPGA which is used to perform 6 major functions (see Figure 13 for details):
•
Connects to GPIOs, lane and chip status and spare pins of PEX 8619 ( for PLX use only)
•
Controls the 7-segment displays for port numbers and link width for PCI Express Cable Connectors J5
and J6 and PCI Express connectors SLOT 1 to SLOT15
•
Decodes lane status and converts them to link speed and status LED display
•
Communicates with the thermal sensor and displays the junction temperature of PEX 8619 in 4 digits
•
Connects to users defined Dipswitches
•
Fans out reset signals to PEX 8619 and PCI Express slots
PEX 8619BA Base Board RDK Hardware Reference Manual – Version 1.0
Copyright © 2008 by PLX Technology, Inc. All rights reserved
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