GAOTek SFP Transceiver with 4.25Gb/s (5km)

This 4.25Gb/s 1310nm SFP (Small form-factor pluggable) Transceiver is used with Single-mode optical fiber to reach up to 3.11 miles (5km) transmission distance.




This 4.25Gb/s 1310nm SFP (Small form-factor pluggable) Transceiver is used with Single-mode optical fiber to reach up to 3.11 miles (5km) transmission distance. It also has a DFB (Distributed Feedback) type transmitter, PIN type receiver, an LD (Laser Driver), a limiting amplifier and digital diagnostic monitor. It is compatible with 1x, 2x, 4x Fiber Channel with data rates 1.06Gb/s, 2.125Gb/s and 4.25Gb/s. The SFP Transceiver is a Class 1 laser safety product which complies with US FDA regulations, SFF-8472 and RoHS standards.

Key Features:

  • Up to 3.11 miles (5km) transmission distance.
  • Up to 4.25Gb/s data links.
  • 1310nm DFB transmitter and PIN Photo-detector.
  • Unique enhanced digital diagnostic monitoring interface.
  • Duplex LC/UPC type pluggable optical interface.
  • Low power dissipation.
  • Metal enclosure, for lower EMI.
  • Single +3.3V power supply
  • RoHS compliant and lead-free.
  • Compliant with SFF-8472
  • Commercial case operating temperature range: 32°F to 158°F (0°C to +70°C)
  • Extended case operating temperature range: 14°F to 176°F (-10°C to +80°C)
  • Industrial case operating temperature range: -40°F to 185°F (-40°C to +85°C)

Technical Specifications:

Protocol2-Wire Serial communication Protocol
Working RangeUp to 3.11 miles (5km)
Memory256-byte memory map in EEPROM
StandardsSFF-8472, SFF-8431 and SFP MSA.

1x,2x,4x FC

Class 1 laser safety

RoHS compliant.

Data rate4.25Gb/s
Fiber Optic Cable9/125µm Single-mode
Digital Diagnostics MonitoringEnabled
Transmitter output optical Power-6 dBm to -1 dBm
Receiver SensitivityData rate at 1.06Gb/s-22 dBm
Data rate at 2.125Gb/s-21 dBm
Data rate at 4.25Gb/s-18 dBm
Receiver Input Saturation Power0.5 dBm
Supply Voltage3.3V
Transmitter Differential Line Input Impedance100Ω
Dimensions2.3in x 0.54in x 0.33in (L 58.4mm x W13.7mm x   H 8.5mm)
Relative Humidity5% to 95% Non-condensing

5% to 70% (Recommended)

Storage Temperature-40 °F to 185 °F (-40°C to 85°C)

Case Operating Temperature

Commercial32°F to 158°F (0°C to +70°C)
Extended14°F to 176°F (-10°C to +80°C)
Industrial-40°F to 185°F (-40°C to +85°C)

Additional Information:


Ideal to be used on applications such as

  • 4xFC at 4.25Gbps
  • 2xFC at 2.125 Gbps
  • 1xFC at 1.0625Gbps
  • 1000 Base-LX Ethernet

Ordering Information:

Product IDData rate(Gb/s)MediaWavelengthTransmission DistanceTemperature RangeSupply Current


4.25Single -mode fiber1310nm3.11 miles (5km)Commercial

32°F to 158°F

(0°C to +70°C)

330 mA


4.25Single -mode fiber1310nm3.11 miles (5km)Extended

14°F to 176°F

(-10°C to +80°C)


330 mA


4.25Single -mode fiber1310nm3.11 miles (5km)Industrial

-40°F to 185°F

(-40°C to +85°C)


330 mA

Digital Diagnostics Functions:

  • GAOTek GAO-SFP-117 series transceivers support the 2-wire serial communication protocol as defined in the SFP MSA1. It is very closely related to the E2PROM defined in the GBIC standard, with the same electrical specifications.
  • Additionally, GAOTek SFP Transceivers provide a unique enhanced digital diagnostic monitoring interface which allows real-time access to device operating parameters such as transmitter optical power, receiver optical power, transceiver temperature, transceiver supply voltage and laser bias current. It defines an alarm system and warning flags, which alerts the end users when particular operating parameters are outside of a factory set normal range.
  • Standard SFP Serial id provides access to identification information that describes the transceiver’s capabilities, standard interfaces, manufacturer and other information.
  • SFP MSA defines a 256-byte memory map in EEPROM that is accessible over a 2 wire serial interface at the 8 bit address 1010000X (A0h). The interface is identical to, and is thus fully backward compatible with both the GBIC Specification and the SFP Multi Source Agreement.
  • The operating and diagnostics information is monitored and reported by a Digital Diagnostics Transceiver Controller (DDTC) inside the transceiver, which is accessed through a 2-wire serial interface. The memories are organized as a series of 8-bit data words that can be addressed individually or sequentially.
  • Digital diagnostics for the GAO-SFP-117 are internally calibrated by default.

Electrical interface characteristics:

Total Supply CurrentICCAmA1
Transmitter Disable Input-HighVDISH2Vcc+0.3V
Transmitter Disable Input-LowVDISL00.8V
Transmitter Fault Input-HighVTxFH2Vcc+0.3V
Transmitter Fault Input-LowVTxFL00.8V
Total Supply CurrentICCBmA1
LOSS Output Voltage-HighVLOSH2Vcc+0.3VLVTTL
LOSS Output Voltage-LowVLOSL00.8V


  1. A (TX)+ B (RX) = 330mA (Not include termination circuit)

Optical Characteristics:

Specification of Transmitter:

Average Output Optical  PowerPOUT-6-1dBm1
Center Wavelengthλc127013101360nmDFB laser
Optical Extinction RatioER6dB
Side Mode Suppression RatioSMSR30dB
Spectrum Bandwidth(-20dB)σ1nm
Transmitter OFF Output PowerPOff-45
Differential Line Input ImpedanceRIN90100110
Output Eye MaskFC-PI-4 requirements


  1. Measure at 2^23-1 NRZ PRBS pattern.

Specification of Receiver:

Receiver Sensitivity @ 1.06Gb/sRSENS1– 22.0dBm1
Receiver Sensitivity @ 2.125Gb/sRSENS2– 21.0dBm1
Receiver Sensitivity @ 4.25Gb/sRSENS3– 18.0dBm1
Wavelength RangeλC12701610nmPIN-TIA
Input Saturation Power (Overload)Psat0.5dBm
LOS AssertLOSA-35dBm
LOS De -AssertLOSD-19dBm
LOS Hysteresis0.526dB2


  1. With worst-case extinction ratio. Measured with a PRBS 27-1 test pattern, BER<10-12
  2. When LOS de-asserted, the RX data+/- output is High-level (fixed)

Pin out of Connector Block on Host Board:

PIN Descriptions:

PinSymbol Name/DescriptionNote
1VEETTransmitter Ground (Common with Receiver Ground)1
2TFaultTransmitter Fault
3TDisTransmitter Disable.2
4MOD_DEF(2)Module Definition 2. Data line for Serial ID.3
5MOD_DEF(1)Module Definition 1. Clock line for Serial ID.3
6MOD_DEF(0)Module Definition 0. Grounded within the module.3
7Rate SelectNo connection required4
8LOSLoss of Signal indication. Logic 0 indicates normal operation5
9VEERReceiver Ground (Common with Transmitter Ground)1
10VEERReceiver Ground (Common with Transmitter Ground)1
11VEERReceiver Ground (Common with Transmitter Ground)1
12RD-Receiver Inverted DATA out. AC coupled
13RD+Receiver Non-inverted DATA out. AC coupled
14VEERReceiver Ground (Common with transmitter Ground)1
15VCCRReceiver power Supply
16VCCTTransmitter Power supply
17VEETTransmitter Ground (Common with receiver Ground)1
18TD+Transmitter Non-Inverted DATA in. AC Coupled.
19TD-Transmitter Inverted DATA in.AC Coupled.
20VEETTransmitter Ground (Common with Receiver Ground)1


  1. Circuit ground is internally isolated from ground.
  2. Laser output disabled when it is open or TDis > 2.0V, enabled on TDis < 0.8V.
  3. Should be pulled up with 4.7kΩ to 10kΩ on host board to a voltage between 2.0V and 3.6V.MOD_DEF (0) pulls the line low to indicate the module is plugged in.
  4. This is an optional input used to control the receiver bandwidth for compatibility with multiple data rates (most likely Fiber Channel 1x and 2x Rates).If implemented, the input will be internally pulled down with > 30kΩ resistor. The input states are:
  • Low (0 – 0.8V) : Reduced Bandwidth
  • (>0.8, < 2.0V) : Undefined
  • High (2.0 – 3.465V) : Full Bandwidth
  • Open : Reduced Bandwidth
  1. Loss of signal is open collector output.
  • It should be pulled up with 4.7 kΩ to 10 kΩ on host board to a voltage between 2.0V and 3.6V.
  • Logic 0 indicates normal operation.
  • Logic 1 indicates loss of signal.

Mechanical Dimensions:

Recommend Circuit Schematic:

Regulatory Compliance:

Laser Eye SafetyFDA 21CFR 1040.10, 1040.11 IEC/EN 60825-1,2Class 1 laser product
Component RecognitionIEC/EN 60950, ULCompatible with standards
ROHS2002/95/ECCompatible with standards
Electrostatic discharge(ESD)IEC/EN 61000-4-2Compatible with standards
EMCEN61000-3Compatible with standards
Electromagnetic Interference(EMI)FCC Part 15 Class B EN 55022 Class B (CISPR 22A)Compatible with standards