VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 3.2Gb/s Laser Diode Driver
VSC7928
Table 1: Signal Pin Reference
Signal
DIN, NDIN
Type
Level
# Pins
Description
In
Out
Out
Out
Pwr
Pwr
In
ECL
ECL
—
2
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
2
1
—
1
VSS
Pwr
Pwr
DC
DC
DC
DC
DC
ECL
DC
DC
DC
DC
DC
—
2
GND
5/6(1)
Positive Voltage Rail
VIP
1
Modulation Gate Node
MIP
In
1
Modulation Source Node
VIB
In
1
Bias Gate Node
MIB
In
1
Bias Source Node
IBIAS
Out
In
1
Laser Bias Output (To Laser Cathode)
Clock Input and Clock Reference, On-chip 50Ω Termination
Data Reference
CLK, NCLK
DINTERM
CLKTERM
DCC
2
In
1
In
1
1
Clock Reference
In
Duty Cycle Control, Leave Floating
Clk/Non-clk Data Select
SEL
In
1
GND/NC
Total Pins
Pwr
—
7(1)
24/32*
No connection (leave floating or connect to GND)
NOTE: (1) Applicable to 32-pin TQFP package only.
Table 2: Mux Select Logic Table
SEL
Mode Select
VSS
GND
N/C
Clocked Data In
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
G52246-0, Rev 3.0
04/05/01
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
