Stratix® II GX devices support a variety of single-ended I/O standards, including LVTTL, LVCMOS, SSTL, HSTL, PCI, and PCI-X standards, which allows Stratix II GX devices to easily interface with backplanes, host processors, buses, memory devices, and other board devices.
Single-ended systems provide more current drive capacity than differential I/O standards, and they are critical when working with advanced memory devices such as double data rate (DDR) SDRAM, DDR2 SDRAM, RLDRAM II, and quad data rate II (QDRII) SRAM devices.
Table 1 lists the single-ended I/O standards supported in Stratix II GX devices.
| Table 1. Stratix II GX Device Single-Ended I/O Standard Support | ||
| I/O Standard | Performance Target | Typical Application |
|---|---|---|
| 3.3-V/2.5-V LVTTL 1.8-V LVTTL |
300 MHz 250 MHz |
General Purpose SDR SDRAM |
| 3.3-V/2.5-V LVCMOS 1.8-V LVCMOS 1.5-V LVCMOS |
300 MHz 250 MHz 200 MHz |
General Purpose |
| SSTL-2 Class I & II | 200 MHz | DDR SDRAM, RLDRAM II |
| SSTL-18 Class I & II | 267 MHz | DDR2 SDRAM |
| 1.8-V HSTL Class I & II | 300 MHz | QDRII SRAM, RLDRAM II |
| 1.5-V HSTL Class I & II | 250 MHz | Memory & Switch Fabric |
| 3.3-V PCI | 66 MHz | PC & Embedded |
| 3.3-V PCI-X | 133 MHz | PC & Embedded |
| Differential SSTL-2 Class I & II | 200 MHz | Memory & Switch Fabric |
| Differential SSTL-18 Class I & II | 267 MHz | DDR2 SDRAM |
| Differential 1.8-V HSTL Class I & II | 300 MHz | QDRII SRAM, RLDRAM II |
| Differential 1.5-V HSTL Class I & II | 250 MHz | Memory & Switch Fabric |
