IDT 89EBPES24T3G2, Manual

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IDT Installation of the EB24T3G2 Eval Board
EB24T3G2 Eval Board Manual 2 - 2 January 21, 2008
Notes The output of the onboard clock generator is accessible through two SMA connectors located on the
Evaluation Board. See Table 2.2. This can be used to connect a scope for probing or capturing purposes
and cannot be used to drive the clock from an external source.
Power Sources
The EB24T3G2 and both downstream ports are powered from the upstream port slot power. 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, W2, and W3 (see Table 2.1
1
)
are used to select proper power source for the switch and all downstream ports.
External Power Source
If necessary, external power is supplied to the EB24T3G2 board through a 4-pin auxiliary power
connector attached to J4. The external power supply pr12V to the EB24T3G2 as described in Table
2.3. The +5V is unused.
PCI Express Analog High Power Voltage Converter
A DC-DC converter (U18) provides a 2.5V PCI Express analog high power voltage (shown as VDDHA)
to the PES24T3G2.
PCI Express Analog Power Voltage Converter
A separate DC-DC converter (U16) provides a 1.0V PCI Express analog power voltage (VDDA) to the
PES24T3G2.
PCI Express Transmitter Analog Power Voltage Converter
A separate DC-DC converter (U17) provides a 1.0V PCI Express transmitter analog power voltage
(shown as VDDPETA) to the PES24T3G2.
Core Logic Voltage Converter
A separate DC-DC converter (U15) provides the 1.0V core voltage (VDDCORE) to the PES24T3G2.
3.3V I/O Voltage Regulator
A 12V to 3.3V voltage regulator (VR1) provides the 3.3V I/O voltage (VDDIO) to the PES24T3G2.
Onboard Reference Clock Output (Differential) – J7, J6
J9 Positive Reference Clock
J10 Negative Reference Clock
Table 2.2 SMA Connectors - Onboard Reference Clock
Pin Signal
1 +12V
2 GND
3 GND
4 +5V
Table 2.3 External Power Connector - J1