8. Using MAX II Devices in Multi-Voltage
Systems
MII51009-1.7
Introduction
Technological advancements in deep submicron processes have lowered the supply
voltage levels of semiconductor devices, creating a design environment where devices
on a system board may potentially use many different supply voltages such as 5.0, 3.3,
2.5, 1.8, and 1.5 V, which can ultimately lead to voltage conflicts.
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To accommodate interfacing with a variety of devices on system boards, MAX II
devices have MultiVolt I/O interfaces that allow devices in a mixed-voltage design
environment to communicate directly with MAX II devices. The MultiVolt interface
separates the power supply voltage (VCCINT) from the output voltage (VCCIO), enabling
MAX II devices to interface with other devices using a different voltage level on the
same printed circuit board (PCB).
Additionally, the MAX II device family supports the MultiVolt core feature. For 1.8-V
operation, use the MAX IIG or MAX IIZ devices. The 1.8-V input directly powers the
core of the devices. For 2.5-V or 3.3-V operation, use the MAX II devices. MAX II
devices that support 2.5-V and 3.3-V operation have an internal voltage regulator that
regulates at 1.8 V.
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This chapter discusses several features that allow you to implement Altera devices in
multiple-voltage systems without damaging the device or the system, including:
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Hot Socketing—Insert or remove MAX II devices to and from a powered-up
system without affecting the device or system operation
Power-Up Sequence Flexibility—MAX II devices can accommodate any possible
power-up sequence
Power-On Reset—MAX II devices maintain a reset state until voltage is within
operating range
This chapter contains the following sections:
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“I/O Standards” on page 8–2
“MultiVolt Core and I/O Operation” on page 8–3
“5.0-V Device Compatibility” on page 8–3
“Recommended Operating Condition for 5.0-V Compatibility” on page 8–7
“Hot Socketing” on page 8–8
“Power-Up Sequencing” on page 8–8
“Power-On Reset” on page 8–8
© October 2008 Altera Corporation
MAX II Device Handbook
ALTERA [ ALTERA CORPORATION ]
