Product Features:
l Supports 25.78Gb/s aggregate bit rate;
l 1310nm EML Laser transmitter and APD/TIA receiver;
l Maximum link length of 40km on;
Single Mode Fiber (SMF);
l Hot-pluggable SFP28 footprint;
l Duplex LC receptacles;
l Single 3.3V power supply;
l Maximum power dissipation < 1.8W;
l RoHS-6 compliant and lead-free;
l I2C management interface;
l Case operating temperature;
Commercial: 0°C to +70°C
Industrial: -40°C to +85°C
I. Pin Diagram

Pinout of Connector Block on Host Board
II.Pin Descriptions
Pin | Symbol | Name/Description | Ref. |
1 | V EET | Transmitter Ground (Common with Receiver Ground) | 1 |
2 | T FAULT | Transmitter Fault. | 2 |
3 | T DIS | Transmitter Disable. Laser output disabled on high or open. | 3 |
4 | SDA | 2-wire Serial Interface Data Line | 4 |
5 | SCL | 2-wire Serial Interface Clock Line | 4 |
6 | MOD_ABS | Module Absent. Grounded within the module | 4 |
7 | RS0 | No connection required | |
8 | LOS | Loss of Signal indication. Logic “0” indicates normal operation. | 5 |
9 | RS1 | No connection required | |
10 | V EER | Receiver Ground (Common with Transmitter Ground) | 1 |
11 | V EER | Receiver Ground (Common with Transmitter Ground) | 1 |
12 | RD- | Receiver Inverted DATA out. AC Coupled | |
13 | RD+ | Receiver Non-inverted DATA out. AC Coupled | |
14 | V EER | Receiver Ground (Common with Transmitter Ground) | 1 |
15 | V CCR | Receiver Power Supply | |
16 | V CCT | Transmitter Power Supply | |
17 | V EET | Transmitter Ground (Common with Receiver Ground) | 1 |
18 | TD+ | Transmitter Non-Inverted DATA in. AC Coupled. | |
19 | TD- | Transmitter Inverted DATA in. AC Coupled. | |
20 | V EET | Transmitter Ground (Common with Receiver Ground) | 1 |
Notes:
1. Circuit ground is internally isolated from chassis ground.
2. TFAULT is an open collector/drain output, which is pulled up with a 4.7kΩ – 10kΩ resistor on the
host board, but is grounded inside the SFP+ cable plug.
3. Laser output disabled on TDIS >2.0V or open, enabled on TDIS <0.8V.
4. Should be pulled up with 4.7kΩ – 10kΩ on host board to a voltage between 2.0V and 3.6V.
MOD_ABS pulls line low to indicate module is plugged in.
5. LOS is open collector output. Should be pulled up with 4.7kΩ – 10kΩ on host board to a voltage
between 2.0V and 3.6V. Logic 0 indicates normal operation; logic 1 indicates loss of signal.
III. Absolute Maximum Ratings
Parameter | Symbol | Min | Type | Max | Unit | Ref. |
Maximum Supply Voltage | Vcc | -0.5 | 3.6 | V | ||
Storage Temperature | TS | -40 | 85 | ℃ | ||
Relative Humidity | RH | 0 | 85 | % |
Notes:
1.Limited by the fiber cable jacket, not the activeends.
2.Non-condensing
IV. Optical Characteristics
Parameter | Symbol | Min. | Typ. | Max. | Unit | Remark |
Transmitter | ||||||
Signaling rate(range) | Sr | 25.7825±100ppm | GBd | |||
Center Wavelength | λc | 1295 | 1310 | nm | ||
Spectral Width(-20dB) | Pm | 1 | nm | |||
Average Output Power | Pavg | -3 | 6 | dBm | ||
Extinction Ratio | ER | 4 | dB | |||
Side Mode Suppression Ratio | SMSR | 30 | dB | |||
Transmitter OFF Output Power | POff | -30 | dBm | |||
Transmitter eye mask definition {X1, X2, X3, Y1, Y2, Y3} Hit ratio 5×10-5 hits per sample. | {0.31, 0.4, 0.45, 0.34, 0.38, 0.4} | |||||
Receiver | ||||||
Signaling rate(range) | Sr | 25.7825±100ppm | GBd | |||
Center Wavelength | λc | 1295 | 1325 | nm | ||
Receiver Sensitivity(OMA) | -19 | dBm | 1 | |||
Receiver Reflectance | Rfl | -26 | dBm | |||
Loss of Signal Assert | PA | -35 | dBm | |||
Loss of Signal De-assert | PD | -19 | dBm | |||
LOS Hysteresis | PD- PA | 0.5 | dB | |||
Note:
1. Hit ratio 5x10-5.
V. Digital Diagnostic Memory Map
VI. Digital Diagnostic Monitoring Information
Parameter | Unit | Accuracy |
Case Temperature | ℃ | ±3 |
Supply Voltage | V | ±3% |
Tx Bias Current | mA | ±10% |
Tx Optical Power | dB | ±3 |
Rx Optical Power | dB | ±3 |
VII. Electrical Interface Characteristics
Parameter | Symbol | Min | Type | Max | Unit | Ref. |
Supply Voltage | Vcc | 3.135 | 3.3 | 3.465 | V | |
Supply Current | Icc | 500 | mA | Commercial | ||
550 | mA | Industrial | ||||
Transmitter | ||||||
Input differential impedance | Rin | 100 | 1 | |||
Differential data input swing | Vin, pp | 100 | 800 | mV | ||
Transmit Disable Voltage | VD | 2 | VCC | V | ||
Transmit Enable Voltage | VEN | Vee | Vee+0.8 | V | ||
Receiver | ||||||
Differential data output swing | Vout, pp | 100 | 800 | mV | 2 | |
LOS Fault | VLOS_fault | 2 | VccHOST | V | 3 | |
LOS Normal | VLOS_norm | Vee | Vee+0.8 | V | 3 | |
Notes:
1. Connected directly to TX data input pins.AC coupling from pins into laser driver IC.
2. Into 100Ω differential termination.
3. LOS is an open collector output. Should be pulled up with 4.7kΩ – 10kΩ on the host board. Normal operation is logic 0; loss of signal is logic 1. Maximum pull-up voltage is 5.5V.
VIII. Mechanical Dimensions (mm)

SFP wire mechanical drawing (Unit: mm)
Product Features
l Supports 25.78Gb/s aggregate bit rate
l 1310nm EML Laser transmitter and APD/TIA receiver
l Maximum link length of 40km on
Single Mode Fiber (SMF)
l Hot-pluggable SFP28 footprint
l Duplex LC receptacles
l Single 3.3V power supply
l Maximum power dissipation < 1.8W
l RoHS-6 compliant and lead-free
l I2C management interface
l Case operating temperature
Commercial: 0°C to +70°C
Industrial: -40°C to +85°C
Applications | Compliance |
25GBASE-LR 25G Ethernet | SFP MSA. |
CPRI 10 | IEEE802.3cc |
SFF-8472 | |
RoHS |
Ordering Information
Package | Product part NO. | Distance | Temperature Range |
FSJMLE31-K40C | 25.78125 | 1310 | 40km |
FSJMLE31-K40I | 25.78125 | 1310 | 40km |
*For availability of additional cable lengths, please contact Fibridge. | |||