Altera Cyclone II EP2C35 PCI Development Board - Manual (Page 18)

2–8 Core Version 4.0.0 Altera Corporation
Cyclone II EP2C35 PCI Development Board Reference Manual May 2005
Component Operation
External Power Jack
Board header J2 is a power receptacle from a standard laptop power
supply.
Table 2–8 shows that the external power switch (SW1) enables the
external power supply.
1
If both the external power and the PCI power are supplied at the
same time, the board draws power from the external power
supply for all power rails except the 5.0-V power rail. Therefore,
when the PCI 3.3-V circuit transistors detect external power
supply voltage, they disable the power from the PCI connector.
The external power switch does not control the power from the
PCI connector.
Test Points
Table 2–9 shows the board’s power supply test points.
Table 2–8. External Power Supply Enable
External Power Switch (SW1)
Position (PWR SWITCH)
Description
Off Disable external power supply
On Enable external power supply
Table 2–9. Board’s Power Supply Test Points
Signal
Name
Reference
Designator
Description
VREF TP4 0.9-V VREF for DDR2 SDRAM
Ground TP5 Ground test point near oscillator socket.
TP1 Ground test point near power connector.
TP2 Ground test point near PWR SWITCH.
TP3 Ground test point near MICTOR.
TP6 Ground test point near DDR2 SDRAM.