
IDT82V3355
SYNCHRONOUS ETHERNET WAN PLL
Electrical Specifications
118
May 19, 2009
8.3.2.3
Single-Ended Input for Differential Input
This is a recommended and tested interface circuit to drive differen-
tial input with a single-ended signal.
Figure 22. Example of Single-Ended Signal to Drive Differential Input
Vth = VCC*[R2/(R1+R2)]
For the example in
Figure 22, R1 = R2, so Vth = VCC/2 =1.65 V
The suggested single-ended signal input:
VIHmax = VCC
VILmin = 0 V
Vswing = 0.6 V ~ VCC
DC offset (Swing Center) = Vth/2 +/- Vswing*10%
VCC = 3.3 V
+
-
Receiver
R2
1K
R1
1K
C1
0.1 uF
R5
100 (Option)
Zo = 50
R4
100 (Option)
Vth
Driver_LVCMOS
Ro ~ 7
VCC = 3.3 V
Rs
43
Ro + Rs = Zo