HC4GX15 Datasheet, PDF (180/668 Pages) Altera Corporation – HardCopy IV Device Handbook

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Chapter 1: HardCopy IV Design Flow Using the Quartus II Software
Quartus II Settings for HardCopy IV Devices
The I/O pins of a Stratix IV device and a HardCopy IV device are arranged in groups
called modular I/O banks. When mapping between a Stratix IV device and a
HardCopy IV device, the I/O pin location must be assigned to the available common
I/O banks for both devices. Because HardCopy IV devices have fewer I/O banks than
Stratix IV devices, the Quartus II software limits the I/O banks to only those available
in HardCopy IV devices.
f For more information about I/O banks and pins in HardCopy IV devices, refer to the
HardCopy IV Device I/O Features chapter.
HardCopy IV I/O buffers support 3.3-V I/O standards. You can use them as
transmitters or receivers in your system. The 3.3-V I/O standard can be supported by
using the bank supply voltage (V_CCIO) at 3.0 V. In this method, the clamp diode
(on-chip or off-chip), when enabled, can sufficiently clamp overshoot voltage to
within the DC and AC input voltage specification. The clamped voltage can be
expressed as the sum of the supply voltage (V_CCIO) and the diode forward voltage.
f For more information about HardCopy IV I/O buffers and the standards they
support, refer to the DC and Switching Characteristics chapter.
f For more information about mapping Stratix IV to HardCopy IV I/Os, refer to the
Mapping Stratix IV Device Resources to HardCopy IV Devices chapter.
It is essential to constrain the I/O standards for the design. If you leave the I/O with
an unassigned I/O assignment, the Quartus II software assigns the I/O standard to
2.5 V by default. This standard may not be compatible with your intended I/O
standard. To check the supported I/O standards and identify incompatible I/O
settings on the assigned I/Os, run the Quartus II I/O Assignment Analysis to verify
the I/O settings and assignments. To run I/O Assignment Analysis, on the Processing
menu, point to Start, then click Start I/O Assignment Analysis.
Figure 1–5 shows the I/O assignment analysis in the Quartus II software.
HardCopy IV Device Handbook, Volume 2
© January 2010 Altera Corporation