HFCT-5942 HP [Agilent(Hewlett-Packard)], HFCT-5942 Datasheet - Page 9

• 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)]

Power Supply Filtering and Ground
Planes
It is important to exercise care
in circuit board layout to
achieve optimum performance
from these transceivers. Figure
6 shows the power supply
circuit which complies with the
small form factor multisource
agreement. It is further
recommended that a
continuous ground plane be
provided in the circuit board
directly under the transceiver
to provide a low inductance
ground for signal return
current. This recommendation
is in keeping with good high
frequency board layout
practices.
Package footprint and front panel
considerations
The Agilent transceivers
comply with the circuit board
“Common Transceiver
Footprint” hole pattern defined
in the current multisource
agreement which defined the 2
x 10 package style. This
drawing is reproduced in
Figure 7 with the addition of
ANSI Y14.5M compliant
dimensioning to be used as a
guide in the mechanical layout
of your circuit board. Figure 8
shows the front panel
dimensions associated with
such a layout.
Eye Safety Circuit
For an optical transmitter
device to be eye-safe in the
event of a single fault failure,
the transmit-ter must either
maintain eye-safe operation or
be disabled.
The HFCT-5942xxx is
intrinsically eye safe and does
not require shut down
circuitry.
9
(0.4 ± 0.004)
Signal Detect
The Signal Detect circuit
provides a deasserted output
signal when the optical link is
broken (or when the remote
transmitter is OFF). The Signal
Detect threshold is set to
transition from a high to low
state between the minimum
receiver input optical power
and
-35 dBm avg. input optical
power indicating a definite
optical fault (e.g. unplugged
connector for the receiver or
transmitter, broken fiber, or
failed far-end transmitter or
data source). The Signal Detect
does not detect receiver data
error or error-rate. Data errors
can be determined by signal
processing offered by upstream
PHY ICs.
Figure 8. Recommended Panel Mounting
10.16 ± 0.1
DIMENSIONS IN MILLIMETERS (INCHES)
1.
2.
FIGURE DESCRIBES THE RECOMMENDED FRONT PANEL OPENING FOR A LC OR SG SFF TRANSCEIVER.
SFF TRANSCEIVER PLACED AT 15.24 mm (0.6) MIN. SPACING.
(0.56 ±0.004)
14.22 ±0.1
15.24
DETAIL A
(0.6)
TOP OF PCB
15.24
(0.6)
B
(0.039)
(0.62 MAX. 0.59 MIN.)
15.75 MAX. 15.0 MIN.
1
Electromagnetic Interference (EMI)
One of a circuit board
designer’s foremost concerns is
the control of electromagnetic
emissions from electronic
equipment. Success in
controlling generated
Electromagnetic Interference
(EMI) enables the designer to
pass a governmental agency’s
EMI regulatory standard and
more importantly, it reduces
the possibility of interference
to neighboring equipment.
Agilent has designed the
HFCT-5942xxx to provide good
EMI performance. The EMI
performance of a chassis is
dependent on physical design
and features which help
improve EMI suppression.
Agilent encourages using
standard RF suppression
practices and avoiding poorly
EMI-sealed enclosures.
A
SECTION B - B
SOLDER POSTS
B