I/O Structure
Figure 2–18. MultiVolt Core Feature in MAX II Devices
Voltage
3.3-V or 2.5-V on
1.8-V Core
Voltage
1.8-V on
VCCINT Pins
Regulator
VCCINT Pins
1.8-V Core
Voltage
MAX II Device
MAX IIG or MAX IIZ Device
IOEs support many features, including:
I/O Structure
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LVTTL and LVCMOS I/O standards
3.3-V, 32-bit, 66-MHz PCI compliance
Joint Test Action Group (JTAG) boundary-scan test (BST) support
Programmable drive strength control
Weak pull-up resistors during power-up and in system
programming
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Slew-rate control
Tri-state buffers with individual output enable control
Bus-hold circuitry
Programmable pull-up resistors in user mode
Unique output enable per pin
Open-drain outputs
Schmitt trigger inputs
Fast I/O connection
Programmable input delay
MAX II device IOEs contain a bidirectional I/O buffer. Figure 2–19 shows
the MAX II IOE structure. Registers from adjacent LABs can drive to or be
driven from the IOE’s bidirectional I/O buffers. The Quartus II software
automatically attempts to place registers in the adjacent LAB with fast
I/O connection to achieve the fastest possible clock-to-output and
registered output enable timing. For input registers, the Quartus II
software automatically routes the register to guarantee zero hold time.
You can set timing assignments in the Quartus II software to achieve
desired I/O timing.
2–28Core Version a.b.c variable
MAX II Device Handbook, Volume 1
Altera Corporation
March 2008