VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7923
Input Termination Schemes
SONET/SDH 2.5Gb/s Laser Diode Driver
Figure 1: Input Structure
OV (GND)
1400
DIN
X
VREF
X
4300
1400
+
-
4300
• Nominal VREF = -1.3V
• 1400, 4300 Ohm Resistor
on die, nominal values
-5.2V (VSS)
Figure 2: Single Ended AC Coupled
GND
0.1µF
SOURCE
GND
DIN
50 Ohms
GND
X
50Ω
VREF
+
X
0.1µF
GND
VSS
-
-2V
Figure 3: Differential AC Coupled
GND
0.1µF
SOURCE
0.1µF
DIN
X
GND
GND
+
50Ω
-2V
X
GND
GND
-
VSS
50Ω
-2V
VREF
G52203-0, Rev 3.0
05/11/01
©
VITESSE
SEMICONDUCTOR CORPORATION
• 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
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