I/O standards Definition
Standards that uniquely define the input and output (VCCIO) voltage, reference VREF voltage (if applicable), and the types of input and output buffers used for I/O pins.
The following table lists I/O standards and the corresponding Quartus® Prime Settings File (.qsf) settings keyword.
To see the standards that a device family supports, refer to the device datasheet.
| I/O Standard | QSF Keyword |
|---|---|
| 1.2-V | "1.2 V", "1.2V", "1.2-V" |
| 1.2-V HSTL Class I and II | "1.2- V HSTL", "1.2- V HSTL Class I", "1.2- V HSTL Class II" |
| 1.2-V HSUL | "1.2-V HSUL" |
| 1.2-VPCML | "1.2- V PCML" |
| 1.4-V PCML | "1.4-V PCML" |
| 1.5-V | "1.5 V", "1.5V", "1.5- V" |
| 1.5-VHSTL Class I | "1.5- V HSTL Class I", "HSTL Class I" |
| 1.5-VHSTL Class II | "1.5- V HSTL Class II", "HSTL Class II" |
| 1.5-VPCML | "1.5- V PCML" |
| 1.8V | "1.8 V", "1.8V", "1.8- V" |
| 1.8-V HSTL Class I and II | "1.8- V HSTL Class I", "1.8- V HSTL Class II" |
| 2.5-V | "2.5 V", "2.5V", "2.5- V" |
| 2.5 V LVDS | LVDS |
| 2.5-V PCML | "2.5-V PCML" |
| 2.5-V Schmitt Trigger Input | "2.5V Schmitt Trigger Input" |
| 3.0-V LVCMOS | "3.0-V LVCMOS", "3.0V LVCMOS" |
| 3.0-V LVTTL | "3.0-V LVTTL", "3.0V LVTTL" |
| 3.0-VPCI | "3.0- V PCI" |
| 3.0-VPCI-X | "3.0- V PCI- X", "3.0- V PCI X" |
| 3.3-V LVCMOS | "3.3-V LVCMOS", "3.3V LVCMOS", "LVCMOS" |
| 3.3-V LVTTL | "LVTTL" |
| 3.3-VPCI | "3.3- V PCI" |
| 3.3-VPCI-X | "3.3-V PCI-X", "3.3- V PCI X" |
| 3.3-VPCML | "3.3- V PCML", "PCML", "CML" |
| 3.3-V Schmitt Trigger Input | "3.3V Schmitt Trigger Input" |
| Bus LVDS | "Bus LVDS" |
| Differential I/O standards | |
| 2.5 V LVDS | LVDS |
| Differential 1.2-V HSTL Class I and II | "Differential 1.2- V HSTL", "Differential 1.2- V HSTL Class I", "Differential 1.2- V HSTL Class II" |
| Differential 1.2-V HSUL | "Differential 1.2-V HSUL" |
| Differential 1.2-V SSTL | "Differential 1.2-V SSTL" |
| Differential 1.25-V SSTL | "Differential 1.25-V SSTL" |
| Differential 1.35-V SSTL | "Differential 1.35-V SSTL" |
| Differential 1.5-V HSTL Class I | "Differential HSTL", "Differential 1.5- V HSTL", "Differential 1.5- V HSTL Class I" |
| Differential 1.5-V HSTL Class II | "Differential HSTL Class II", "Differential 1.5- V HSTL Class II" |
| Differential 1.5-V SSTL | "Differential 1.5-V SSTL" |
| Differential 1.5-V SSTL ClassIand II | "Differential 1.5-V SSTL Class I", "Differential 1.5-V SSTL Class II" |
| Differential 1.8-V HSTL ClassIand II | "Differential 1.8- V HSTL Class I", "Differential 1.8- V HSTL Class II" |
| Differential 1.8-V SSTL ClassIand II | "Differential 1.8- V SSTL Class I", "Differential 1.8- V SSTL Class II" |
| Differential 2.5-V SSTL ClassIand II | "Differential 2.5- V SSTL Class I" "Differential 2.5- V SSTL Class II" |
| Differential LVPECL | "Differential LVPECL" |
| Differential SSTL-2 ClassI | "Differential SSTL- 2" |
| Differential SSTL-2 ClassII | "Differential SSTL- 2 Class II" |
| HCSL | "HCSL" |
| LVDS | "LVDS" |
| LVDS_E_1R | "LVDS_E_1R" |
| LVDS_E_3R | "LVDS_E_3R" |
| LVPECL | LVEPCL |
| mini-LVDS | "mini-LVDS" |
| mini-LVDS _E_R | "mini-LVDS", |
| mini-LVDS _E_3R | "mini-LVDS", |
| RSDS | "RSDS" |
| RSDS_E_1R | "RSDS_E_1R" |
| RSDS_E_3R | "RSDS_E_3R" |
| Schmitt Trigger Input | "2.5V Schmitt Trigger Input", "3.3V Schmitt Trigger Input" |
| SSTL-12 | "SSTL-12" |
| SSTL-125 Class I | "SSTL-125" |
| SSTL-135 Class I | "SSTL-135" |
| SSTL-15 | "SSTL-15" |
| SSTL-15 Class I | "SSTL- 15 Class I" |
| SSTL-15 Class II | "SSTL- 15 Class II" |
| SSTL-18 Class I and II | "SSTL- 18 Class I", "SSTL- 18 Class II" |
| SSTL-2 Class I and II | "SSTL- 2 Class I", "SSTL- 2 Class II" |
| POD12 | "1.2-V POD |
| Differential POD12 | "Differential 1.2-V POD |
| High Speed Differential | "High Speed Differential I/O" |
| PPDS | "PPDS" |
| PPDS_E_3R | "PPDS_E_3R" |
| SLVS | "SLVS" |
| mini-LVDS_E_1R | "mini-LVDS_E_1R" |
| mini-LVDS_E_3R | "mini-LVDS_E_3R |
| CML | "CURRENT MODE LOGIC (CML)" |
| 1.5-V Schmitt Trigger Input | "1.5V Schmitt Trigger Input" |
| 1.8-V Schmitt Trigger Input | "1.8V Schmitt Trigger Input" |
| HiSpi | "HISPI" |
| Sub-LVDS | "SUB-LVDS" |
| TMDS | TMDS |