AFCT-5971LZ Avago Technologies US Inc., AFCT-5971LZ Datasheet - Page 7

• Manufacturer Part Number: AFCT-5971LZ
• Description: TXRX FE SM LASER 125MBS 2X5
• Manufacturer: Avago Technologies US Inc.

Specifications of AFCT-5971LZ

• Applications: Ethernet
• Data Rate: 125MBd
• Wavelength: 1300nm
• Voltage - Supply: 3.1 V ~ 3.5 V
• Connector Type: LC Duplex
• Mounting Type: Through Hole
• Data Rate Max: 0.125Gbps
• Supply Voltage: 3.3V
• Wavelength Typ: 1300nm
• Leaded Process Compatible: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Application Information
The Applications Engineering Group at Avago Tech-
nologies is available to assist you with technical under-
standing and design trade-offs associated with these
transceivers. You can contact them through your Avago
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 optical power (dBm
avg) and the lowest receiver sensitivity (dBm avg). This
OPB provides the necessary optical signal range to es-
tablish 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.
Figure 6a. Recommended dc Coupled Interface Circuit
T
7
Note:
* C4 AND C5 ARE OPTIONAL BYPASS CAPACITORS FOR ADDITIONAL
LOW FREQUENCY NOISE FILTERING.
DIS
T
R
X
X
(LVTTL)
C1 = C2 = C3 = 10 nF or 100 nF
10
1
9
2
8
3
TRANSCEIVER INPUTS
7
TERMINATE AT
4
130 Ω
6
5
100 Ω
130 Ω
C1
C2
1 µH
1 µH
C5 *
10 µF
C4 *
10 µF
Electrical and Mechanical Interface
Recommended Circuit
Figures a and b show recommended dc and ac
coupled circuits for deploying the Avago Technologies
transceivers in +3.3 V systems.
Data Line Interconnections
Avago Technologies’ AFCT-5971LZ/ALZ fiber-optic
transceivers are designed to couple to +3.3 V PECL sig-
nals. The transmitter driver circuit regulates the output
optical power. The regulated light output will maintain
a constant output optical power provided the data pat-
tern is reasonably 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.
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
V
CC
C3
(+3.3 V)
10 µF
130 Ω
100 Ω
DEVICE INPUTS
TERMINATE AT
130 Ω
82 Ω
V
CC
130 Ω
(+3.3 V)
TD-
TD+
RD+
RD-
SD
PHY DEVICE
V
CC
V
LVPECL
LVPECL
CC
(+3.3 V)
(+3.3 V)