VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
VSC7927
Table 1: Signal Pin Reference
Signal
DIN, NDIN
Type
Level
# Pins
Description
In
Out
Out
Out
Pwr
Pwr
In
ECL
ECL
—
2
2
1
1
2
5
1
1
1
1
1
2
1
1
1
1
24
Data Input and Data Reference, On-chip 50Ω Termination
Data Density Differential Outputs
Laser Modulation Current Output (Complementary)
Laser Modulation Current Output (to Laser Cathode)
Negative Voltage Rail
MK, NMK
NIOUT
IOUT
—
VSS
Pwr
Pwr
DC
DC
DC
DC
DC
ECL
DC
DC
DC
DC
—
GND
Positive Voltage Rail
VIP
Modulation Gate Node
MIP
In
Modulation Source Node
VIB
In
Bias Gate Node
MIB
In
Bias Source Node
IBIAS
CLK, NCLK
DINTERM
CLKTERM
DCC
Out
In
Laser Bias Output (To Laser Cathode)
Clock Input and Clock Reference, On-chip 50Ω Termination
Data Reference
In
In
Clock Reference
In
Duty Cycle Control, Leave Floating
Clk/Non-clk Data Select
SEL
In
Total Pins
—
Table 2: Mux Select Logic Table
SEL
Mode Select
Clocked Data In
VSS
GND
N/C
Non-clocked Data In
Non-clocked Data In
Table 3: Absolute Maximum Ratings
Symbol
Rating
Limit
VSS
TJ
Negative Power Supply Voltage
Maximum Junction Temperature
Storage Temperature
VCC to -6.0V
-55°C to + 125°C
-65°C to +150°C
TSTG
Table 4: Recommended Operating Conditions
Symbol
Parameter
Positive Voltage Rail
Min
Typ
Max
Units
Conditions
GND
VSS
TCl
—
-5.5
-40
—
0
—
-4.9
85(2)
125
V
V
Negative Voltage Rail
Operational Temperature(1)
Junction Temperature
-5.2
—
—
°C
°C
Power dissipation = 1.3W
TJ
NOTES: (1) Lower limit of specification is ambient temperature and upper limit is case temperature. (2) See section “Calculation of the
Maximum Case Temperature” for detailed maximum temperature calculations.
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
Page 2
G52201-0, Rev 3.0
04/05/01/01
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
