
Spartan-3E FPGA Family: DC and Switching Characteristics
DS312 (v4.1) July 19, 2013
Product Specification
120
Single-Ended I/O Standards
Table 80: Recommended Operating Conditions for User I/Os Using Single-Ended Standards
IOSTANDARD
Attribute
VREF
VIL
Min (V)
Nom (V)
Max (V)
Min (V)
Nom (V)
Max (V)
Min (V)
LVTTL
3.0
3.3
3.465
VREF is not used for
these I/O standards
0.8
2.0
3.0
3.3
3.465
0.8
2.0
2.3
2.5
2.7
0.7
1.7
LVCMOS18
1.65
1.8
1.95
0.4
0.8
LVCMOS15
1.4
1.5
1.6
0.4
0.8
LVCMOS12
1.1
1.2
1.3
0.4
0.7
3.0
3.3
3.465
0.3
VCCO
0.5
VCCO
3.0
3.3
3.465
0.3
VCCO
0.5
VCCO
HSTL_I_18
1.7
1.8
1.9
0.8
0.9
1.1
VREF - 0.1
VREF + 0.1
HSTL_III_18
1.7
1.8
1.9
-
1.1
-
VREF - 0.1
VREF + 0.1
SSTL18_I
1.7
1.8
1.9
0.833
0.900
0.969
VREF - 0.125
VREF + 0.125
SSTL2_I
2.3
2.5
2.7
1.15
1.25
1.35
VREF - 0.125
VREF + 0.125
Notes:
1.
Descriptions of the symbols used in this table are as follows:
VCCO – the supply voltage for output drivers
VREF – the reference voltage for setting the input switching threshold
VIL – the input voltage that indicates a Low logic level
VIH – the input voltage that indicates a High logic level
2.
The VCCO rails supply only output drivers, not input circuits.
3.
For device operation, the maximum signal voltage (VIH max) may be as high as VIN max. See Table 73. 4.
There is approximately 100 mV of hysteresis on inputs using LVCMOS33 and LVCMOS25 I/O standards.
5.
All Dedicated pins (PROG_B, DONE, TCK, TDI, TDO, and TMS) use the LVCMOS25 standard and draw power from the VCCAUX rail (2.5V).
The Dual-Purpose configuration pins use the LVCMOS standard before the User mode. When using these pins as part of a standard 2.5V
configuration interface, apply 2.5V to the VCCO lines of Banks 0, 1, and 2 at power-on as well as throughout configuration.
6.
For information on PCI IP solutions, see
www.xilinx.com/pci. The PCIX IOSTANDARD is available and has equivalent characteristics but no
PCI-X IP is supported.