EP4CE55F23C8 Altera, EP4CE55F23C8 Datasheet - Page 130

• Manufacturer Part Number: EP4CE55F23C8
• Description: IC CYCLONE IV FPGA 55K 484FBGA
• Manufacturer: Altera
• Series: CYCLONE® IV Er

Specifications of EP4CE55F23C8

• Number Of Logic Elements/cells: 55856
• Number Of Labs/clbs: 3491
• Total Ram Bits: 2340000
• Number Of I /o: 324
• Voltage - Supply: 1.15 V ~ 1.25 V
• Mounting Type: Surface Mount
• Operating Temperature: 0°C ~ 85°C
• Package / Case: 484-FBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Gates: -

6–22
High-Speed Differential Interfaces
External Memory Interfacing
Pad Placement and DC Guidelines
Pad Placement
Cyclone IV Device Handbook, Volume 1
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Cyclone IV devices can send and receive data through LVDS signals. For the LVDS
transmitter and receiver, the input and output pins of Cyclone IV devices support
serialization and deserialization through internal logic.
The BLVDS extends the benefits of LVDS to multipoint applications such as
bidirectional backplanes. The loading effect and the need to terminate the bus at both
ends for multipoint applications require BLVDS to drive out a higher current than
LVDS to produce a comparable voltage swing. All the I/O banks of Cyclone IV
devices support BLVDS for user I/O pins.
The RSDS and mini-LVDS standards are derivatives of the LVDS standard. The RSDS
and mini-LVDS I/O standards are similar in electrical characteristics to LVDS, but
have a smaller voltage swing and therefore provide increased power benefits and
reduced electromagnetic interference (EMI).
The PPDS standard is the next generation of the RSDS standard introduced by
National Semiconductor Corporation. Cyclone IV devices meet the National
Semiconductor Corporation PPDS Interface Specification and support the PPDS
standard for outputs only. All the I/O banks of Cyclone IV devices support the PPDS
standard for output pins only.
The LVDS standard does not require an input reference voltage, but it does require a
100- termination resistor between the two signals at the input buffer. An external
resistor network is required on the transmitter side for the top and bottom I/O banks.
Cyclone IV devices support I/O standards required to interface with a broad range of
external memory interfaces, such as DDR SDRAM, DDR2 SDRAM, and QDR II
SRAM.
For more information about Cyclone IV devices external memory interface support,
refer to the
You can use the Quartus II software to validate your pad and pin 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 depend on device
density, package, I/O assignments, voltage assignments and other factors that are not
fully described in this chapter.
For more information about how the Quartus II software checks I/O restrictions, refer
to the
I/O Management
External Memory Interfaces in Cyclone IV Devices
chapter in volume 2 of the Quartus II Handbook.
Chapter 6: I/O Features in Cyclone IV Devices
© December 2010 Altera Corporation
chapter.
Pad Placement and DC Guidelines