Altera Cyclone III FPGA, Reference Manual

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2–22 Reference Manual Altera Corporation
Cyclone III FPGA Starter Board October 2007
Power Supply
Power Supply
The power supply block distributes clean power from the 12 V input
supply to the Cyclone III device through on-board regulators.
To provide various voltage options, the board uses several Linear
Technologies’ regulators. Switching regulators are used for digital circuits
and linear regulators are used for analog circuits. Board regulators are
used to generate the voltages listed in
Table 2–18 .
f
You can measure the core and I/O voltage with a current meter while the
Cyclone III device is in standby mode. For more information on this
circuit, refer to the
Cyclone III FPGA Starter Kit Getting Started User Guide .
Table 2–18. Board Regulators
Output
Voltage
(V)
Variance
(+/- mV)
MAX
Current
(A)
Board
Access
Point
Regulator
Board
Reference
Linear
Technologies
Part #
Where Used
1.20 50 3.0 JP6 (1) REG4 LT1959CS8 Cyclone III Core voltage
1.25 50 1.0 JP4 REG2 LTC3413 DDR termination voltage
2.50 50 6.0 JP3 (1) REG1 LTM4603EV DDR, SRAM, Flash, PLLs, other
bias voltages
1.80 80 1.5 JP7 REG5 LT1959CS8 Parallel flash interface, USB buffers
and other I/O
3.30 100 2.0 JP5 REG3 LT1959CS8 I/O voltage and power for most
components including HSMC
12.00 200 1.0 SW1 N/A N/A Input supply voltage. All other
voltages (including HSMC voltage)
are derive from this regulator.
Note to Table 2–18 :
(1) A 0.01 current sense resistor has been added to select jumper points for FPGA core power and I/O power
measurement.