Stratix Architecture
Table 2–26. External RAM Support in EP1S60 & EP1S80 Devices
Maximum Clock Rate (MHz)
-5 Speed Grade -6 Speed Grade -7 Speed Grade
DDR Memory Type
I/O Standard
DDR SDRAM (1), (2)
SSTL-2
167
150
133
167
200
167
133
133
167
200
133
133
133
133
167
DDR SDRAM - side banks (2), (3) SSTL-2
QDR SRAM (4)
QDRII SRAM (4)
ZBT SRAM (5)
1.5-V HSTL
1.5-V HSTL
LVTTL
Notes to Table 2–26:
(1) These maximum clock rates apply if the Stratix device uses DQS phase-shift circuitry to interface with DDR
SDRAM. DQS phase-shift circuitry is only available in the top and bottom I/O banks (I/O banks 3, 4, 7, and 8).
(2) For more information on DDR SDRAM, see AN 342: Interfacing DDR SDRAM with Stratix & Stratix GX Devices.
(3) DDR SDRAM is supported on the Stratix device side I/O banks (I/O banks 1, 2, 5, and 6) without dedicated DQS
phase-shift circuitry. The read DQS signal is ignored in this mode. Numbers are preliminary.
(4) For more information on QDR or QDRII SRAM, see AN 349: QDR SRAM Controller Reference Design for Stratix &
Stratix GX Devices.
(5) For more information on ZBT SRAM, see AN 329: ZBT SRAM Controller Reference Design for Stratix & Stratix GX
Devices.
In addition to six I/O registers and one input latch in the IOE for
interfacing to these high-speed memory interfaces, Stratix devices also
have dedicated circuitry for interfacing with DDR SDRAM. In every
Stratix device, the I/O banks at the top (I/O banks 3 and 4) and bottom
(I/O banks 7 and 8) of the device support DDR SDRAM up to 200 MHz.
These pins support DQS signals with DQ bus modes of ×8, ×16, or ×32.
Table 2–27 shows the number of DQ and DQS buses that are supported
per device.
Table 2–27. DQS & DQ Bus Mode Support (Part 1 of 2) Note (1)
Number of ×8
Groups
Number of ×16
Groups
Number of ×32
Groups
Device
Package
EP1S10
672-pin BGA
12 (2)
0
0
672-pin FineLine BGA
484-pin FineLine BGA
780-pin FineLine BGA
16 (3)
0
4
EP1S20
484-pin FineLine BGA
18(4)
16(3)
7 (5)
7 (5)
4
4
672-pin BGA
672-pin FineLine BGA
780-pin FineLine BGA
20
7 (5)
4
Altera Corporation
July 2005
2–117
Stratix Device Handbook, Volume 1
ALTERA [ ALTERA CORPORATION ]
