Voltage Regulators; Ml555 Dc Power System - Xilinx Virtex-5 FPGA ML555 User Manual

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Voltage Regulators

The ML555 board is powered from either the PCI slot that it is plugged into, utilizing the
+5V and the +3.3V power rails (see
edge connector pinout), or the PCI Express slot that it is plugged into utilizing the +3.3V
and +12V power rails.

ML555 DC Power System

The ML555 board plugs into either a parallel PCI bus slot or a serial PCI Express slot in a
system unit. PCI and PCI Express designs use different connector systems for add-in cards.
System units provide unique DC voltages to the add-in cards through the connectors. PCI
system units provide 3.3V and 5V, while PCI Express system units provide 3.3V and 12V to
add-in cards. For PCI Express applications, the ML555 board converts the 12V supply to
5V before powering the onboard voltage regulators. For PCI applications, most of the
onboard regulators are powered by 5V provided by the system units.
The GTP transceiver analog supplies and the FPGA V
either 3.3V from the PCI Express connector or a 5V to 3.0V DC converter on the ML555
board. Two configuration headers are provided on the ML555 board to select between the
5V and 3.3V power sources as indicated in
diagram of the ML555 voltage regulator topology.
Virtex-5 FPGA ML555 Development Kit
UG201 (v1.4) March 10, 2008
Table 3-4 for the specific power pins within the PCI
Table 3-30
www.xilinx.com
Voltage Regulators
voltage are sourced from
CCINT
and Table 3-31. Figure 3-14 is a block
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