Other Members of Agilent SC Duplex
155 Mb/s Product Family
ELECTRICAL SUBASSEMBLY
PIN PHOTODIODE
DATA
DATA
PRE-
AMPLIFIER
IC
• HFCT-5801, 1300 nm single
mode transceiver for links up
to 15 km. The part is based on
the 2 x 9 industry standard
package and has laser bias,
optical power monitor and
transmitter disable functions.
POST
AMPLIFIER IC
OPTICAL
SUB-
DUPLEX SC
RECEPTACLE
SIGNAL DETECT
ASSEMBLIES
DATA
DATA
LASER
DRIVER
IC
LASER
Applications Information
Typical BER Performance of Receiver
versus Input Optical Power Level
The HFCT-5805 transceiver can
be operated at Bit-Error-Rate
conditions other than the
TOP VIEW
Figure 1. Block Diagram
-10
required BER = 1 x 10 of the
Transmitter Section
The transmitter section of the
Receiver Signal Detect
Signal Detect is a basic fiber
HFCT-5805 consists of a 1300 nm failure indicator. This is a
InGaAsP laser in an eyesafe single-ended LVPECL output. As
optical subassembly (OSA) which the input optical power is
mates to the fiber cable. The laser decreased, Signal Detect will
ATM Forum 155.52 Mb/s Physical
Layer Standard. The typical
trade-off of BER versus Relative
Input Optical Power is shown in
Figure 2. The Relative Input
Optical Power in dB is
OSA is driven by a custom IC
switch from high to low (deassert
which converts differential input point) somewhere between
referenced to the actual
sensitivity of the device. For BER
LVPECL logic signals into an
analog laser drive current.
sensitivity and the no light input
level. As the input optical power
is increased from very low levels,
Signal Detect will switch back
from low to high (assert point).
The assert level will be at least
0.5 dB higher than the deassert
level.
-10
conditions better than 1 x 10
,
more input signal is needed (+dB).
Receiver Section
The receiver utilizes an InGaAs
PIN photodiode mounted
together with a transimpedance
preamplifier IC in an OSA. This
OSA is connected to a circuit
providing post- amplification
quantization, and optical signal
detection.
Transceiver Specified for Wide
Temperature Range Operation
The HFCT-5805 is specified for
operation over normal commercial
temperature range of 0° to +70°C
(HFCT-5805B/D) or the extended
temperature range of -40° to
+85°C (HFCT-5805A/C).
Characterization of the parts has
been performed over the ambient
operating temperature range in
an airflow of 2 m/s.
2