Transmitter Sections
The transmitter section of the
AFBR-5803Z and AFBR-5805Z
series utilize 1300 nm Surface
Emitting InGaAsP LEDs. These
LEDs are packaged in the
optical subassembly portion of
the transmitter section. They
are driven by a custom silicon
IC which converts differential
PECL logic signals, ECL
referenced (shifted) to a +3.3 V
or +5 V supply, into an analog
LED drive current.
Receiver Sections
The receiver sections of the
AFBR-5803Z and AFBR-5805Z
series utilize InGaAs PIN
photodiodes coupled to a
custom silicon transimpedance
preamplifier IC. These are
packaged in the optical sub-
assembly portion of the
receiver.
These PIN/preamplifier combi-
nations are coupled to a
custom quantizer IC which
provides the final pulse
shaping for the logic output
and the Signal Detect function.
The data output is differential.
The signal detect output is
single-ended. Both data and
signal detect outputs are PECL
compatible, ECL referenced
(shifted) to a +3.3 V or +5 V
power supply.
Package
The overall package concept
for the Agilent transceivers
consists of the following basic
elements; two optical
subassemblies, an electrical
subassembly and the housing
as illustrated in Figure 1 and
Figure 1a.
The package outline drawings
and pin out are shown in
Figures 2, 2a and 3. The
details of this package outline
and pin out are compliant
with the multisource definition
of the 1 x 9 SIP. The low
profile of the Agilent
transceiver design complies
with the maximum height
allowed for the duplex SC
connector over the entire
length of the package.
The optical subassemblies
utilize a high volume assembly
process together with low cost
lens elements which result in a
cost effective building block.
The electrical subassembly
consists of a high volume
multilayer printed circuit
board on which the IC chips
and various surface-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
nonconductive plastic to
provide mechanical strength
and electrical isolation. The
solder posts of the Agilent
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 transceiver by mating
with duplex or simplex SC or
ST connectored fiber cables.
ELECTRICAL SUBASSEMBLY
DIFFERENTIAL
DATA OUT
SINGLE-ENDED
SIGNAL
DETECT OUT
QUANTIZER IC
PREAMP IC
DUPLEX SC
RECEPTACLE
PIN PHOTODIODE
OPTICAL
SUBASSEMBLIES
DIFFERENTIAL
DATA IN
DRIVER IC
LED
TOP VIEW
Figure 1. SC Connector Block Diagram.
2
AGILENT [ AGILENT TECHNOLOGIES, LTD. ]
