EP3C120F484C7 Datasheet, PDF (119/274 Pages) Altera Corporation – Cyclone III Device Handbook

Chapter 6: I/O Features in the Cyclone III Device Family
Pad Placement and DC Guidelines
6–21
Pad Placement and DC Guidelines
Pad Placement
Altera recommends that you create a Quartus II design, enter your device I/O
assignments, and compile your design to validate your pin placement. The Quartus II
software checks your pin connections with respect to the I/O assignment and
placement rules to ensure proper device operation. These rules are dependent on
device density, package, I/O assignments, voltage assignments, and other factors that
are not fully described in this chapter.
f For more information about how the Quartus II software checks I/O restrictions, refer
to the I/O Management chapter in volume 2 of the Quartus II Handbook.
DC Guidelines
For the Quartus II software to automatically check for illegally placed pads according
to the DC guidelines, set the DC current sink or source value to Electromigration
Current assignment on each of the output pins that are connected to the external
resistive load.
The programmable current strength setting has an impact on the amount of DC
current that an output pin can source or sink. Determine if the current strength setting
is sufficient for the external resistive load condition on the output pin.
Document Revision History
Table 6–7 lists the revision history for this document.
Table 6–7. Document Revision History (Part 1 of 3)
Date
July 2012
December 2011
December 2009
July 2009
June 2009
Version
Changes
3.4 Updated OCT with or without calibration note in “Slew Rate Control” section,
■ Updated Table 6–1 and Table 6–4.
■ Updated “Programmable Pull-Up Resistor” on page 6–5, “OCT Support” on page 6–7,
3.3
and “I/O Standards” on page 6–11.
■ Updated hyperlinks.
■ Minor text edits.
3.2 Minor changes to the text.
3.1 Made minor correction to the part number.
Updated to include Cyclone III LS information
■ Updated chapter part number.
■ Updated “Introduction” on page 6–1, “PCI-Clamp Diode” on page 6–6, “On-Chip Series
3.0
Termination Without Calibration” on page 6–10, “I/O Standards” on page 6–11, “I/O
Banks” on page 6–16, “High-Speed Differential Interfaces” on page 6–20, and “External
Memory Interfacing” on page 6–20.
■ Updated Table 6–6 on page 6–18.
July 2012 Altera Corporation
Cyclone III Device Handbook
Volume 1