IDT EB8T5A Eval Board, Руководство пользователя

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IDT Installation of the EB8T5A Eval Board
EB8T5A Eval Board Manual 2 - 3 July 23, 2009
Notes
Figure 2.1 Clock Distribution Block Diagram
Power Sources
Power for the EB8T5A is generated from the 12.0V PCI Express upstream slot power or optionally from
3.3Vaux. A 12.0V to 3.3V DC-DC converter will be used to provide power to four DC-DC converters to
generate VDDcore, VDDpe, VDDpea, and VTT voltages. The 3.3V from the 12.0V converter is used to
power VDDio. When in power down mode the DC-DC converters is powered directly from 3.3Vaux through
a MOSFET switch.
If add-in cards require more power than the upstream slot can support, an external source is required to
supply this extra power via an auxiliary 4-pin power connector on the board. Header W1, W5, and W11 (see
Table 2.15) are used to select the proper power source for the switch and all downstream ports.
External Power Source
If necessary, external power is supplied to the EB8T5A board through a 4-pin auxiliary power connector
attached to J4. The external power supply pr12V to the EB8T5A as described in Table 2.5. The
+5V is unused.
Pin Signal
1 +12V
2 GND
3 GND
4 +5V
Table 2.5 External Power Connector - J4
PEREFCLK0
Port2
Port3
Port4
Port5
Upstream PEREFCLK
25MHz
ICS557-06
ICS9DB803D
SMA - J18,J19
ISC9FG104