mounted passive circuit elements
are attached.
The package includes internal
shields for the electrical and
optical subassemblies to ensure
low EMI emissions and high
immunity to external EMI fields.
The outer housing including the
duplex SC connector receptacle
or the duplex ST ports is molded
of filled non-conductive plastic to
provide mechanical strength and
electrical isolation. The solder
posts of the Hewlett-Packard
design are isolated from the
circuit design of the transceiver
and do not require connection to
a ground plane on the circuit
board.
The transceiver is attached to a
printed circuit board with the
nine signal pins and the two
solder posts which exit the
bottom of the housing. The two
solder posts provide the primary
mechanical strength to withstand
the loads imposed on the trans-
ceiver by mating with duplex or
simplex SC or ST connectored
fiber cables.
Transceiver Optical Power
Budget versus Link Length
Optical Power Budget (OPB) is
the available optical power for a
fiber optic link to accommodate
fiber cable losses plus losses due
to in-line connectors, splices,
optical switches, and to provide
margin for link aging and
unplanned losses due to cable
plant reconfiguration or repair.
Figure 4 illustrates the predicted
OPB associated with the three
transceiver series specified in this
data sheet at the Beginning of
Life (BOL). These curves
represent the attenuation and
chromatic plus modal dispersion
losses associated with the 62.5/
125
µm
and 50/125
µm
fiber
cables only. The area under the
curves represents the remaining
OPB at any link length, which is
available for overcoming non-
fiber cable related losses.
Hewlett-Packard LED technology
has produced 800 nm LED and
1300 nm LED devices with lower
aging characteristics than
normally associated with these
technologies in the industry. The
industry convention is 3 dB aging
for 800 nm and 1.5 dB aging for
1300 nm LEDs. The HP 1300 nm
LEDs will experience less than
1 dB of aging over normal com-
mercial equipment mission life
periods. Contact your Hewlett-
Packard sales representative for
additional details.
Figure 4 was generated with a
Hewlett-Packard fiber optic link
model containing the current
industry conventions for fiber
cable specifications and the FDDI
PMD and LCF-PMD optical
parameters. These parameters
are reflected in the guaranteed
performance of the transceiver
specifications in this data sheet.
This same model has been used
extensively in the ANSI and IEEE
committees, including the ANSI
X3T9.5 committee, to establish
the optical performance require-
ments for various fiber optic
interface standards. The cable
parameters used come from the
ISO/IEC JTC1/SC 25/WG3
Generic Cabling for Customer
Premises per DIS 11801 docu-
Application Information
OPTICAL POWER BUDGET (dB)
14
12
10
8
6
HFBR-5104,
50/125 µm
The Applications Engineering
group in the Hewlett-Packard
Optical Communication Division
is available to assist you with the
technical understanding and
design trade-offs associated with
these transceivers. You can
contact them through your
Hewlett-Packard sales
representative.
The following information is
provided to answer some of the
most common questions about
the use of these parts.
HFBR-5103, 62.5/125 µm
HFBR-5104,
62.5/125 µm
HFBR-5103,
50/125 µm
4
2
0
HFBR-5105,
50/125 µm
HFBR-5105,
62.5/125 µm
0.15 0.5 1.0
1.5
2.0
2.5
3.0
3.5 4.0
FIBER OPTIC CABLE LENGTH (km)
Figure 4. Optical Power Budget at BOL versus
Fiber Optic Cable Length.
130
AGILENT [ AGILENT TECHNOLOGIES, LTD. ]
