30 Altera Corporation
AN 117: Us ing Sel ectab l e I/O Standards In A PEX 20KE, APEX 20K C & MA X 7000B Devic es
Conclusion The a dv anced pr og r am mab l e I /O fe atures and standa r ds sim plify b oar d
design by minimizing the number of devices used to interface with
memory, microprocessors, and backplanes. The APEX 20KE devices,
which are 64-bit, 66-MHz PCI compliant, support 16 programmable I/O
standards, allowing customization for a wide variety of applications.
Input, output, and bidirectional pins of different I/O standards can be
intermix ed with I/O banks by followi ng the guidelin es in this document.
APEX 20KE devices also offer increased I/O performance with new
standards and features like LVDS (840 Mbps data transfer).
References ■Interface Standard for Nominal 3 V/3.3 V Supply Digital Integrated
Circuits, JESD8-A, Electronic Industries Association, June 1994.
■Stub-Series Terminated Logic for 3.3 Volts (SSTL-3), EIA/JESD8-8,
Electr onic Ind ustrie s Ass o cia tion , August 199 6.
■Stub-Series Terminated Logic for 2.5 Volts (SSTL-2), EIA/JESD8-9,
Electr onic Ind ustrie s Ass o cia tion , Septem ber 1998.
■Electrical Characteristics of Low Voltage Differential Signaling (LVDS)
Interface Circuits, ANS I/TIA/ EIA- 644, Ameri can N atio nal Sta ndar ds
Institute/Telecommunication Industry Association/Electronic
Industries Association.
■2.5 V ±0.2 V (Normal Range) and 1.7 V to 2.7 V (Wide Range) Power
Supply Voltage and Interface Standard for Nonterminated Digital
Integrated Circuit, EIA/JESD8-5, Electronic Industries Associ at i on,
Octob e r 19 95.
■1.8 V ±0.15 V (Normal Range) and 1.2 V to 1.95 V (Wide Range) Power
Supply Voltage and Interface Standard for Nonterminated Digital
Integrated Circuit, EIA/JESD8-7, Electronic Industries Associ at i on,
Februa r y 19 97.
■PCI Local Bus Specification, Revision 2.2, PCI Special Interest
Grou p, De cemb e r 19 98.
Revision
History
The information contained in Application Note 117 (Using Selectable
I/OSta ndards in APEX 20KE, APEX 20KC & MAX 7000B Devices) version
2.1 supersedes information published in previous versions. Application
Note 117 (Using Selectable I/OStan dards in APEX 20KE, APEX 20KC &
MAX 7000B Devices) version 2.1 contains the folllowing change: The title
has been changed throughout the document.