Chapter 1: Cyclone IV FPGA Device Family Overview 1–9
Cyclone IV Device Family Architecture
March 2016 Altera Corporation Cyclone IV Device Handbook,
Cyclone IV device I/O supports programmable bus hold, programmable pull-up
resistors, programmable delay, programmable drive strength, programmable
slew-rate control to optimize signal integrity, and hot socketing. Cyclone IV devices
support calibrated on-chip series termination (Rs OCT) or driver impedance matching
(Rs) for single-ended I/O standards. In Cyclone IV GX devices, the high-speed
transceiver I/Os are located on the left side of the device. The top, bottom, and right
sides can implement general-purpose user I/Os.
Table 1–8 lists the I/O standards that Cyclone IV devices support.
The LVDS SERDES is implemented in the core of the device using logic elements.
fFor more information, refer to the I/O Features in Cyclone IV Devices chapter.
Cyclone IV devices include up to 30 global clock (GCLK) networks and up to eight
PLLs with five outputs per PLL to provide robust clock management and synthesis.
You can dynamically reconfigure Cyclone IV device PLLs in user mode to change the
clock frequency or phase.
Cyclone IV GX devices support two types of PLLs: multipurpose PLLs and general-
■Use multipurpose PLLs for clocking the transceiver blocks. You can also use them
for general-purpose clocking when they are not used for transceiver clocking.
■Use general purpose PLLs for general-purpose applications in the fabric and
periphery, such as external memory interfaces. Some of the general purpose PLLs
can support transceiver clocking.
fFor more information, refer to the Clock Networks and PLLs in Cyclone IV Devices
External Memory Interfaces
Cyclone IV devices support SDR, DDR, DDR2 SDRAM, and QDRII SRAM interfaces
on the top, bottom, and right sides of the device. Cyclone IV E devices also support
these interfaces on the left side of the device. Interfaces may span two or more sides of
the device to allow more flexible board design. The Altera® DDR SDRAM memory
interface solution consists of a PHY interface and a memory controller. Altera supplies
the PHY IP and you can use it in conjunction with your own custom memory
controller or an Altera-provided memory controller. Cyclone IV devices support the
use of error correction coding (ECC) bits on DDR and DDR2 SDRAM interfaces.
Table 1–8. I/O Standards Support for the Cyclone IV Device Family
Type I/O Standard
Single-Ended I/O LVTTL, LVCMOS, SSTL, HSTL, PCI, and PCI-X
Differential I/O SSTL, HSTL, LVPECL, BLVDS, LVDS, mini-LVDS, RSDS, and PPDS