HFCT-5942 HP [Agilent(Hewlett-Packard)], HFCT-5942 Datasheet - Page 7

• Manufacturer Part Number: HFCT-5942
• Description: Single Mode Laser Small Form Factor Transceivers for ATM, SONET OC-48/SDH STM-16 Part of the Agilent METRAK family
• Manufacturer: HP [Agilent(Hewlett-Packard)]

T
B
P
P
B
V
Note:
Note A: CIRCUIT ASSUMES OPEN EMITTER OUTPUT.
Note B: CIRCUIT ASSUMES HIGH IMPENDANCE INTERNAL BIAS @ V
Note C: THE BIAS RESISTOR FOR VpdR SHOULD NOT EXCEED 2 kW.
Application Information
The Applications Engineering
Group at Agilent is available
to assist you with technical
understanding and design
trade-offs associated with
these transceivers. You can
contact them through your
Agilent sales representative.
The following information is
provided to answer some of
the most common questions
about the use of the parts.
Optical Power Budget and
Link Penalties
The worst-case Optical Power
Budget (OPB) in dB for a
fiber-optic link is determined
by the difference between the
minimum transmitter output
Figure 6. Recommended Interface Circuit
7
DIS
MON
MON
MON
CC
MON
T
R
X
X
RX (+3.3 V)
(LVTTL)
+
-
+
-
NOTE C
C1 = C2 = C3 = 10 nF or 100 nF
TD+, TD- INPUTS ARE INTERNALLY TERMINATED AND AC COUPLED.
RD+, RD- OUTPUTS ARE INTERNALLY BIASED AND AC COUPLED.
2 kW
20 19 18 17 16 15 14 13 12 11
1
3 k
2
3
10 nF
4
5
6
7
8
optical power (dBm avg) and
the lowest receiver sensitivity
(dBm avg). This OPB provides
the necessary optical signal
range to establish a working
fiber-optic link. The OPB is
allocated for the fiber-optic
cable length and the
corresponding link penalties.
For proper link performance,
all penalties that affect the
link performance must be
accounted for within the link
optical power budget.
Electrical and Mechanical Interface
Recommended Circuit
Figure 6 shows the
recommended interface for
deploying the Agilent
transceivers in a +3.3 V
system.
9 10
CC
- 1.3 V.
C2
C1
10 µF
10 µF
1 µH
1 µH
Z = 50 W
Z = 50 W
Z = 50 W
Z = 50 W
V
CC
(+3.3 V)
C3
Data Line Interconnections
Agilent’s HFCT-5942xxx fiber-
optic transceivers are designed
to couple to +3.3 V PECL
signals. The transmitter driver
circuit regulates the output
optical power. The regulated
light output will maintain a
constant output optical power
provided the data pattern is
balanced in duty cycle. If the
data duty cycle has long,
continuous state times (low or
high data duty cycle), then the
output optical power will
gradually change its average
output optical power level to
its preset value.
130 W
100 W
130 W
TD-
TD+
RD+
RD-
SD
LVTTL
V
CC
V
(+3.3 V)
CC
(+3.3 V)
NOTE A
NOTE B