VSC7989
Data Sheet
S
PECIFICATIONS
Over recommended operating conditions unless otherwised noted. Tested at V
SS
= -5.2V.
AC Characteristics
Table 1. High-Speed Inputs/Outputs
Symbol
IRL
ORL
Parameter
Input Return Loss
,
50
Ω
System
Output Return Loss, 50
Ω
System
Min
Typ
Max
Unit
dB
dB
Condition
50MHz to 10GHz
50MHz to 10GHz
−
12
−
8
Table 2. Laser Driver
Symbol
t
R
, t
F
Jitter
Parameter
Output Rise and Fall Times
Output Jitter
Overshoot/Undershoot
DCC
Duty Cycle
Min
Typ
28
13
Max
35
15
+10
+20
Unit
ps
ps/p-p
%
%
DCC in the range of V
SS
−
0.5V
to V
SS
+2V.
Condition
50
Ω
load, 20% to 80%,
V
MOD
= 2.5V
50
Ω
Load. V
MOD
= 2.5V
−
10
−
10
DC Characteristics
Table 3. Laser Driver
Symbol
V
BIAS
V
MOD
Parameter
Programmable Output Offset Voltage
Modulation Voltage Amplitude
VSC7989CD
VSC7989CD-01
V
OCM
IB, IBN
VIP
V
IH
V
IL
V
SW
Output Voltage Compliance
Output Offset Control Voltage
Laser Modulation Control Voltage
Input HIGH Voltage
Input LOW Voltage
Input Voltage Swing
(1,2)
VSC7989CD
VSC7989CD-01
V
DCC
Duty-Cycle Control Voltage
900
800
V
SS
2000
2000
V
SS
+2.0
mVp-p
mVp-p
V
Differential
Differential
-10
V
SS
-150
-1.00
1.8
1.8
3.0
0
V
SS
+0.7
0
-0.60
2.5
2.6
V
V
V
V
V
mV
V
At V
BIAS
= 0V
At V
BIAS
= 0V
Min
-0.7
Typ
Max
0
Unit
V
Condition
At IB = IBN = -10V
1.
For single-ended AC-coupled inputs, a DC bias must be applied. Please contact your local Vitesse sales representative for informa-
tion.
2.
Refer to VSC7989 Evaluation Manual for proper circuit to stabilize modulation voltage.
Table 4. Power Dissipation
Symbol
I
VSS
P
D
Parameter
Power Supply Current (V
SS
)
Total Power Dissipation
Min
Typ
300
1560
Max
310
1705
Unit
mA
mW
Condition
V
SS
= -5.2V, R
L
= 50
Ω
to GND
V
BIAS
= 0V, I
MOD
= 120mA
V
SS
= -5.2V, R
L
= 50
Ω
to GND
V
BIAS
= 0V, I
MOD
= 120mA
2 of 10
G52356, Rev 4.1
6/28/02
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
