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Spartan-3A DSP FPGA Family: DC and Switching Characteristics
DS610 (v3.0) October 4, 2010
www.xilinx.com
Product Specification
16
Differential I/O Standards
Differential Input Pairs
X-Ref Target - Figure 3
Figure 3:
Differential Input Voltages
Table 12:
Recommended Operating Conditions for User I/Os Using Differential Signal Standards
IOSTANDARD Attribute
V
CCO
for Drivers
(1)
V
ID
V
ICM
(2)
Min (V)
Nom (V)
Max (V)
Min (mV) Nom (mV) Max (mV)
Min (V)
Nom (V)
Max (V)
LVDS_25
(3)
2.25
2.5
2.75
100
350
600
0.3
1.25
2.35
LVDS_33
(3)
3.0
3.3
3.6
100
350
600
0.3
1.25
2.35
BLVDS_25
(4)
2.25
2.5
2.75
100
300
–
0.3
1.3
2.35
MINI_LVDS_25
(3)
2.25
2.5
2.75
200
–
600
0.3
1.2
1.95
MINI_LVDS_33
(3)
3.0
3.3
3.6
200
–
600
0.3
1.2
1.95
LVPECL_25
(5)
Inputs Only
100
800
1000
0.3
1.2
1.95
LVPECL_33
(5)
Inputs Only
100
800
1000
0.3
1.2
2.8
(6)
RSDS_25
(3)
2.25
2.5
2.75
100
200
–
0.3
1.2
1.5
RSDS_33
(3)
3.0
3.3
3.6
100
200
–
0.3
1.2
1.5
TMDS_33
(3,4,7)
3.14
3.3
3.47
150
–
1200
2.7
–
3.23
PPDS_25
(3)
2.25
2.5
2.75
100
–
400
0.2
–
2.3
PPDS_33
(3)
3.0
3.3
3.6
100
–
400
0.2
–
2.3
DIFF_HSTL_I_18
1.7
1.8
1.9
100
–
–
0.8
–
1.1
DIFF_HSTL_II_18
(8)
1.7
1.8
1.9
100
–
–
0.8
–
1.1
DIFF_HSTL_III_18
1.7
1.8
1.9
100
–
–
0.8
–
1.1
DIFF_HSTL_I
1.4
1.5
1.6
100
–
–
0.68
–
0.9
DIFF_HSTL_III
1.4
1.5
1.6
100
–
–
–
0.9
–
DIFF_SSTL18_I
1.7
1.8
1.9
100
–
–
0.7
–
1.1
DIFF_SSTL18_II
(8)
1.7
1.8
1.9
100
–
–
0.7
–
1.1
DIFF_SSTL2_I
2.3
2.5
2.7
100
–
–
1.0
–
1.5
DIFF_SSTL2_II
(8)
2.3
2.5
2.7
100
–
–
1.0
–
1.5
DIFF_SSTL3_I
3.0
3.3
3.6
100
–
–
1.1
–
1.9
DIFF_SSTL3_II
3.0
3.3
3.6
100
–
–
1.1
–
1.9
Notes:
1.
The V
CCO
rails supply only differential output drivers, not input circuits.
2.
V
ICM
must be less than V
CCAUX
.
3.
These true differential output standards are supported only on FPGA banks 0 and 2. Inputs are unrestricted. See the chapter "Using I/O Resources" in
UG331
.
4.
See
"External Termination Requirements for Differential I/O."
5.
LVPECL is supported on inputs only, not outputs. LVPECL_33 requires V
CCAUX
= 3.3V ± 10%.
6.
LVPECL_33 maximum V
ICM
= the lower of 2.8V or V
CCAUX
– (V
ID
/2).
7.
Requires V
CCAUX
= 3.3V ±10%. (V
CCAUX
- 300 mV)
≤
V
ICM
≤
(V
CCAUX
- 37 mV).
8.
These higher-drive output standards are supported only on FPGA banks 1 and 3. Inputs are unrestricted. See the chapter "Using I/O Resources" in
UG331
.
9.
All standards except for LVPECL and TMDS can have VCCAUX at either 2.5V or 3.3V. Define your VCCAUX level using the CONFIG VCCAUX constraint.
DS610-3_03_061507
V
INN
V
INN
V
INP
V
INP
GND level
50%
V
ICM
V
ICM
= Input common mode voltage =
V
ID
Internal
Logic
Differential
I/O Pair Pins
N
P
2
V
INP
+ V
INN
V
ID
= Differential input voltage = V
INP
- V
INN