VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7923
SONET/SDH 2.5Gb/s Laser Diode Driver
Input Termination Schemes
Figure 1: Input Structure
OV (GND)
DIN X
VREF X
1400
4300
1400
+
-
4300
• Nominal VREF = -1.3V
• 1400, 4300 Ohm Resistor
on die, nominal values
SOURCE
SOURCE
-5.2V (VSS)
Figure 2: Single Ended AC Coupled
GND
50 Ohms
0.1µF
DIN
X
+
GND
GND 50Ω
VREF
X
-
-2V
0.1µF
GND
VSS
Figure 3: Differential AC Coupled
GND
0.1µF
DIN
X
+
GND
GND
50Ω 0.1µF
X
-
GND
GND -2V
50Ω
VREF
-2V
VSS
G52203-0, Rev 3.0
05/11/01
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Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
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