XP2 Datasheet, PDF (57/92 Pages) Lattice Semiconductor – LatticeXP2 Family Data Sheet

Lattice Semiconductor
DC and Switching Characteristics
LatticeXP2 Family Data Sheet
MLVDS
The LatticeXP2 devices support the differential MLVDS standard. This standard is emulated using complementary
LVCMOS outputs in conjunction with a parallel resistor across the driver outputs. The MLVDS input standard is sup-
ported by the LVDS differential input buffer. The scheme shown in Figure 3-5 is one possible solution for MLVDS
standard implementation. Resistor values in Figure 3-5 are industry standard values for 1% resistors.
Figure 3-5. MLVDS (Reduced Swing Differential Standard)
2.5V
16mA
RS =
35ohms
Heavily loaded backplace, effective Zo~50 to 70 ohms differential
RS =
35ohms
2.5V
16mA
2.5V
16mA
+
-
RTL 50 to 70 ohms +/-1%
RS =
35ohms
RS =
35ohms
RS =
35ohms
...
50 to 70 ohms +/-1% R_TR
RS =
35ohms
RS =
35ohms
RS =
35ohms
2.5V
16mA
2.5V
2.5V
16mA
16mA
2.5V
2.5V
16mA
16mA
Table 3-5. MLVDS DC Conditions¹
Parameter
Description
V_CCIO
Output Driver Supply (+/-5%)
Z_OUT
Driver Impedance
R_S
Driver Series Resistor (+/-1%)
R_TLEFT
Driver Parallel Resistor (+/-1%)
R_TRIGHT
Receiver Termination (+/-1%)
V_OH
Output High Voltage (After R₁)
V_OL
Output Low Voltage (After R₁)
V_OD
Output Differential Voltage (After R₁)
V_CM
Output Common Mode Voltage
I_DC
DC Output Current
1. For input buffer, see LVDS table.
Typical
Zo=50Ω Zo=70Ω
2.50
2.50
10.00
10.00
35.00
35.00
50.00
70.00
50.00
70.00
1.52
1.60
0.98
0.90
0.54
0.70
1.25
1.25
21.74
20.00
Units
V
Ω
Ω
Ω
Ω
V
V
V
V
mA
For further information on LVPECL, RSDS, MLVDS, BLVDS and other differential interfaces please see details of
additional technical information at the end of this data sheet.
3-13