VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
SDH/SONET 2.5 Gb/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
Data Input and Data Reference, On-chip 50¾ 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
5/6*
GND
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 50¾ Termination
Data Reference
CLK, NCLK
DINTERM
CLKTERM
DCC
2
In
1
In
1
Clock Reference
In
1
Duty Cycle Control, Leave Floating
Clk/Non-clk Data Select
SEL
In
1
7*
24/32*
GND/NC
Pwr
No connection (leave floating or connect to GND)
Total Pins
—
* 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
-55C to + 125C
-65C to +150C
Tstg
Page 2
VITESSE SEMICONDUCTOR CORPORATION
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896
G52201-0, Rev 2.2
10/13/99
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
