MAX3890ECB-D Maxim Integrated, MAX3890ECB-D Datasheet - Page 8

• Manufacturer Part Number: MAX3890ECB-D
• Description: Serializers & Deserializers - Serdes 3.3V 2.5Gbps SDH/ SONET 16
• Manufacturer: Maxim Integrated

Figure 4 shows alternative PECL-output termination
methods. Use Thevenin-equivalent termination when a
(V
coupling is necessary, be sure that the coupling capac-
itor is placed following the 50Ω or Thevenin-equivalent
DC termination.
For best performance, use good high-frequency layout
techniques. Filter voltage supplies and keep ground
connections short. Use multiple vias where possible.
Also, use controlled-impedance transmission lines to
interface with the MAX3890 clock and data inputs and
outputs.
The EP 64-pin TQFP incorporates features that provide
a very low thermal resistance path for heat removal
from the IC to a PC board. The MAX3890’s exposed
pad must be soldered directly to a ground plane with
good thermal conductance.
+3.3V, 2.5Gbps, SDH/SONET 16:1 Serializer
with Clock Synthesis and LVDS Inputs
Figure 3. Current-Mode Logic
8
CC
_______________________________________________________________________________________
- 2V) termination voltage is not available. If AC-
Alternative PECL-Output Termination
Applications Information
Exposed Pad (EP) Package
50Ω
V
GND
CC
Layout Techniques
OUTPUT CIRCUIT
50Ω
STRUCTURE
ESD
SLBO+
SLBO-
Figure 4. Alternative PECL-Output Termination
MAX3890
MAX3890
OR SDO+
OR SDO+
OR SDO-
OR SDO-
SCLKO+
SCLKO+
SCLKO-
SCLKO-
V
SLBI+
SLBI-
CC
50Ω
V
CC
Z
Z
Z
Z
+3.3V
0
0
0
0
INPUT CIRCUIT
- 2V
= 50Ω
= 50Ω
= 50Ω
= 50Ω
130Ω
50Ω
50Ω
82Ω
130Ω
50Ω
82Ω
HIGH-
IMPEDANCE
INPUTS
PECL
INPUTS