1.25G SFP Transceiver
MXP-243S
Applications:
1.25Gb/s 1000Base-LX Ethernet
1.0625Gb/s Fiber Channel
Features:
Operating bit rate
1.25Gb/s
Operating at
1280-1330nm wavelength
Single +3.3V power
supply
Differential LVPECL
inputs and outputs
TTL signal detect
indicator
Industry standard
small form pluggable
(SFP) package
Hot-pluggable
capability
Duplex LC connector
Metal enclosure, for
lower EMI
Very low jitter
Low power
dissipation
Link length up to
20km in 9/125 SMF
Description
MXP-243S SFP transceiver is an excellent product , which is a series of
high performance optical modules suitable for the Fiber optic communication
and Ethernet accessing for signal that rates up to 1.25Gb/s.
The transmitter section of MXP-243S SFP incorporates 1310nm FP laser as
the optical source. And the receiver section consists of a PIN photodiode mounted
together with a trans-impedance preamplifier (TIA).
Because of its hot-pluggable capability , MXP-243S SFP transceiver can
be installed in or removed from any MSA compliant pluggable small form
factor port
regardless of whether the host equipment is operating or not.
Furthermore , MXP-243S SFP transceiver features an E/EPROM that
contains the detailed product’s information stored for retrieval by host
equipment. For further information, please refer to SFP Multi-Source
Agreement (MSA).
The transceiver operates at up to1.25G data-rate from a single +3.3 V
power supply only. And it uses TTL signal as detect indicator.
Specification:
Operating Information
Part Number
MXP-243S
Input/Output
AC/AC
Signal Detect
TTL
Voltage
+3.3V
Temperature
0℃ to70℃
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Transmitter Optical, Electrical Characteristics
Parameter
Input differential impedance
Differential data input swing
Transmit Disable Input High Voltage
Transmit Disable Input Low Voltage
Transmit Fault OutputHighVoltage
Transmit Fault Output LowVoltage
Transmit Disable Assert Time
Optical Transmit Power
Extinction Ratio
Output Spectrum Width(RMS)
P
O
ER
∆λ
-9.5
9
4
0.14
2.0
0.8
5
-3
Symbol
R
in
V
in
PP
100
2.0
0.8
Min
Typ
100
1200
Max
Unit
Ω
mV
V
V
V
V
µs
dBm
dB
nm
Average Power
Note
Receiver Optical, Electrical Characteristics
Parameter
Single ended data output swing
Receiver Loss of Signal Output
Voltage -high
Receiver Loss of Signal Output
Voltage -low
Sensitivity
Maximum Input Power
Signal detect Range
Signal detect-Hysteresis
Sen
P
inMAX
-3
-30
0.5
-21
Symbol
V
out
PP
Min
200
2
0.8
-20
Typ
Max
800
Unit
mV
V
V
dBm
dBm
dBm
dB
BER<1E-10
Note
Absolute Maximum Ratings
Parameter
Storage Temperature
Operating Temperature
Power Supply Voltage
Symbol
T
S
T
O
V
CC
Min
-40
0
-0.5
Max
+85
+70
6.0
Unit
℃
℃
V
Note
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Pin View：
20
19
18
17
16
15
14
13
12
11
VEET
TD-
TD+
VEET
VCCT
VCCR
VEER
RD+
RD-
VEER
1
2
3
4
5
6
7
8
9
10
VEET
TX Fault
TX Disable
MOD_DEF(2)
MOD_DEF(1)
MOD_DEF(0)
Rate Select
LOS
VEER
VEER
Top of board
Bottom of board
Pin
Assignment:
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Name
VEET
TXFAULT
TXDIS
MOD_DEF(2)
MOD_DEF(1)
MOD_DEF(0)
Rate Select
LOS
VEER
VEER
VEER
RD-
RD+
VEER
VCCR
VCCT
VEET
TD+
TD-
VEET
Transmitter Ground
Transmitter Fault.
Transmitter Disable.
SDA Serial Data Signal
SCL Serial Clock Signal
Grounded within the module.
No connection required
Description
Loss of Signal indication. Logic 0 indicates normal operation.
Receiver Ground
Receiver Ground
Receiver Ground
Receiver Inverted DATA out.
Receiver Non-inverted DATA out.
Receiver Ground
Receiver Power Supply
Transmitter Power Supply
Transmitter Ground
Transmitter Non-Inverted DATA in.
Transmitter Inverted DATA in.
Transmitter Ground
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Block Diagram Of Transceiver
Transmitter Section
The
transmitter
section
RXLOS
RXd-
RXd+
RECEIVER
LIMITING AMP
DATA+
DATA-
VCC
consists of 1310nm FP
laser in an eye safe optical
subassembly (OSA) which
mates to the fiber cable.
The laser OSA is driven by
a LD driver IC which
converts differential input
LVPECL logic signals into
an analog laser driving
current.
CONNECTOR
MOD_DEF(2)
MOD_DEF(1)
MOD_DEF(0)
TRANSMITTER
BIAS
TXd+
TXd-
TX-DIS
TX-FAULT
DRIVER
DATA+
PM
TX-FAULT
TX Fault is an open collector/drain output, which should be pulled up with a 4.7K –
10KΩ resistor on the host board. Pull up voltage between 2.0V and VccT, R+0.3V. When
high, output indicates a laser fault of some kind. Low indicates normal operation. In the
low state, the output will be pulled to < 0.8V.
When sensing an improper power level in the laser driver, the SFP sets this signal
high and turns off the laser. TX-FAULT can be reset with the TX-DISABLE line. The
signal is in TTL level.
TX-DISABLE
TX disable is an input that is used to shut down the transmitter optical output. It is
pulled up within the module with a 4.7 – 10 KΩ resistor. Its states are: Low (0 – 0.8V):
Transmitter on; (>0.8, < 2.0V): Undefined; High (2.0 – 3.465V): Transmitter Disabled;
Open: Transmitter Disabled. The TX-DISABLE signal is high (TTL logic “1”) to turn off
the laser output. The laser will turn on when TX-DISABLE is low (TTL logic “0”).
TD-/+
These are the differential transmitter inputs. They are AC-coupled, differential lines
with 100Ω differential termination inside the module. The AC coupling is done inside the
module and is thus not required on the host board. The inputs will accept differential
swings of 500 – 2400 mV (250 – 1200 mV single-ended), though it is recommended that
values between 500 and 1200 mV differential (250 – 600 mV single-ended) be used for
best EMI performance.
LD
LD
DATA-
VCC
PT
ID E PROM
2
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Receiver Section
The receiver utilizes an InGaAs PIN photodiode mounted together with a
trans-impedance preamplifier IC in an OSA. This OSA is connected to a circuit providing
post-amplification quantization, and optical signal detection.
RX-LOS
LOS (Loss of Signal) is an open collector/drain output, which should be pulled up
with a 4.7K – 10KΩresistor. Pull up voltage between 2.0V and VccT, R+0.3V. When high,
this output indicates the received optical power is below the worst-case receiver sensitivity
(as defined by the standard in use). Low indicates normal operation. In the low state, the
output will be pulled to < 0.8V.
The RX-LOS is high (TTL logic “1”) when there is no incoming light from the
companion transceiver. This signal is normally used by the system for the diagnostic
purpose. The signal is operated in TTL level.
RD-/+
These are the differential receiver outputs. They are AC coupled 100Ω differential
lines which should be terminated with 100
Ω(differential)
at the user SERDES. The AC
coupling is done inside the module and is thus not required on the host board. The voltage
swing on these lines will be between 370 and 2000 mV differential (185 – 1000 mV single
ended) when properly terminated.
Recommended Interface Circuit
Host Board
DC+3.3V
4.7K to 10KΩ
TX-DISABLE
SFP Module
DC+3.3V
4.7K to 10KΩ
TX-FAULT
SerDat OUT+
TX-DAT
TX-DATQ
DC+3.3V
Z0=50Ω
Z0=50Ω
PECL
2X150Ω
SerDat OUT-
Laser
driver
DC+3.3V
SerDat IN-
Z0=50Ω
Z0=50Ω
RX-DATQ
RX-DAT
PECL
DC+3.3V
4.7K to 10KΩ
SerDat IN+
Amplifier
RX-LOS
DC +3.3V
3X4.7K to 10KΩ
MOD-DEF(2)
MOD-DEF(1)
MOD-DEF(0)
EEPROM
RGND
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