Pcb Design Requirements; Power Conditioning; Voltage Regulation; Table 4-11: Transceiver Power Supplies - Xilinx RocketIO X User Manual

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PCB Design Requirements

To ensure reliable operation of theRocketIO X transceivers, certain requirements must be
met by the designer. This section outlines these requirements governing power filtering
networks, high-speed differential signal traces, and reference clocks. Any designs that do
not adhere to these requirements are not supported by Xilinx, Inc.

Power Conditioning

Each RocketIO X transceiver has five power supply pins, all of which are sensitive to noise.
Table
estimated power requirements.
To operate properly, RocketIO X transceivers require a certain level of noise isolation from
surrounding noise sources. For this reason, it is required that both dedicated voltage
regulators and passive high-frequency filtering be used to power RocketIO X circuitry.

Table 4-11: Transceiver Power Supplies

Supply Voltage
AVCCAUXTX 2.5V
AVCCAUXRX 1.5V
VTTX 1.5V
VTRX 0.25–2.5V
GNDA 0.0V
Notes:
1. Power listed is the estimated power per MGT for the individual supply over all MGT operating modes. The total power per MGT is
mode specific and less than the sum total of these values.
2. Power figures shown do not include power requirements of V
respectively.
3. Dependent on mode, voltage level, swing, and emphasis settings.
4. Dependent on termination style, voltage level, and swing. For 100Ω differential termination, VTRX is unconnected (0 mW). Refer to
Figure 4-28.

Voltage Regulation

The transceiver voltage regulator circuits must not be shared with any other supplies
(including FPGA supplies V
shared among transceiver power supplies of the same voltage; however, each supply pin
must still have its own separate passive filtering network.
One of the following devices are required as voltage regulators:
•
•
•
114
4-11, summarizes the power supply pins, their names, associated voltages, and
(1)
Power
2.5 Gb/s (mW) 5 Gb/s (mW)
TBD
TBD
TBD
TBD
TBD
CC
CCINT
Linear Technology LT1963 (LT1963A) 1.5A low-dropout (LDO) (For more information
about this device, visit http://www.linear-
tech.com/prod/datasheet.html?datasheet=886.)
Texas Instruments TPS795xx 500mA RF LDO (For more information about this device, visit
http://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=TPS79518.)
Texas Instruments TPS796xx 1A RF LDO (For more information about this device, visit
http://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=TPS79618.)
www.xilinx.com
1-800-255-7778
Chapter 4: Analog Design Considerations
(2)
Power Power
10 Gb/s (mW)
TBD 125
TBD 141
(3)
TBD 108
(4)
TBD 12
TBD N/A
(82 mW) and V (140 mW), which power the PCS and PMA,
CCAUX
, V , V , and V
CCO CCAUX
Description
Analog 2.5V supply
Analog 1.5V supply
TX termination supply
RX termination supply
Analog ground for transmit
and receive analog supplies
). Voltage regulators can be
REF
RocketIO™ X Transceiver User Guide
UG035 (v1.5) November 22, 2004