GAOTek SFP Transceiver with 155Mb/s (≤2km)

This 155Mb/s 850nm SFP (Small form-factor pluggable) Transceiver is used with Multi-mode optical fiber to reach up to 1804.46ft. (550m) transmission distance.




This 155Mb/s 850nm SFP (Small form-factor pluggable) Transceiver is used with Multi-mode optical fiber to reach up to 1804.46ft. (550m) transmission distance. It has a VSCEL (vertical-cavity surface-emitting laser) type transmitter, PIN type receiver, an LD (Laser Driver), a limiting amplifier and digital diagnostic monitor. The SFP Transceiver is also a Class 1 laser safety product which complies with US FDA regulations, SFP MSA, SFF-8472 and RoHS standards.

Key Features:

  • Up to 1804.46ft. (550m) transmission distance.
  • Up to 155Mb/s data links
  • 850nm VSCEL transmitter and PIN Photo-detector.
  • Unique enhanced digital diagnostic monitoring interface.
  • Duplex LC/UPC type pluggable optical interface.
  • Hot-pluggable SFP footprint.
  • Metal enclosure, for lower EMI.
  • Single +3.3V power supply
  • Compliant with SFF-8472
  • Low power dissipation
  • 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:

Protocol 2-Wire Serial communication Protocol
Working Range Up to 1804.46ft. (550m)
Memory 256-byte memory map in EEPROM
Standards SFF-8472 and SFP MSA

Class 1 laser safety

RoHS compliant.

Data rate 155Mb/s
Wavelength 850nm
Fiber Optic Cable 50/125um multi-mode
Transmitter VSCEL
Receiver PIN
Connector LC
Digital Diagnostics Monitoring Enabled
Transmitter output optical Power -9 dBm to -3 dBm
Receiver Sensitivity -24 dBm
Receiver Input Saturation Power -6 dBm
Supply Voltage 3.3V
Transmitter Differential Line Input Impedance 100Ω
Dimensions 2.3in x 0.54in x 0.33in (L 58.4mm x W13.7mm x   H 8.5mm)
Relative Humidity 5% to 95% Non-condensing

5% to 70% (Recommended)

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

Case Operating Temperature

Commercial 32°F to 158°F (0°C to +70°C)
Extended 14°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

  • Router/Server Interface
  • Other Optical Links
  • Fast Ethernet
  • Switched Backplane Applications
  • Switch to Switch Interface

Ordering Information:

Product ID Data rate(Mb/s) Media Wavelength Transmission Distance Temperature Range Supply Current


155 multi-mode fiber 850nm 1804.46ft. (550m) Commercial

32°F to 158°F

(0°C to +70°C)

280 mA


155 multi-mode fiber 850nm 1804.46ft. (550m) Extended

14°F to 176°F

(-10°C to +80°C)


280 mA


155 multi-mode fiber 850nm 1804.46ft. (550m) Industrial

-40°F to 185°F

(-40°C to +85°C)


280 mA

Digital Diagnostics Functions:

  • GAOTek GAO-SFP-108 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-108 are internally calibrated by default.

Electrical Interface Characteristics:

Parameter Symbol Min Typ. Max Unit Note
Total Supply Current ICC A mA 1
Transmitter Disable Input-High VDISH 2 Vcc+0.3 V
Transmitter Disable Input-Low VDISL 0 0.8 V
Transmitter Fault Input-High VDISL 2 Vcc+0.3 V
Transmitter Fault Input-Low VTxFH 0 0.8 V  
Total Supply Current Icc B mA 1
LOSS Output Voltage-High VLOSH 2 Vcc+0.3 V  


LOSS Output Voltage-Low VLOSL 0 0.8 V


  1. A (TX) + B (RX) = 280mA (Not include termination circuit)

Optical Characteristics:

Specification of Transmitter:

Parameter Symbol Min Type Max Unit Note
Average Output Power POUT -9 -3 dBm
Center Wavelength λC 830 850 860 nm VSCEL Laser
Spectrum Bandwidth(RMS) σ 0.85 nm
Optical Extinction Ratio ER 8.2 dB
Transmitter OFF Output Power POff -45 dBm
Jitter P-P tJ 0.1 UI 1
Output Eye Mask Compliant with G.957(class 1 laser safety) 2
Differential Line Input Impedance RIN 90 100 110 Ohm


  1. Measure at 2^23-1 NRZ PRBS pattern
  2. Transmitter eye mask definition

Specification of Receiver:

Parameter Symbol Min Type Max Unit Note
Receiver Sensitivity PIN -24 dBm 1
Input Optical Wavelength λIN 770 850 860 nm PIN-TIA
Input Saturation Power (Overload) Psat -6 dBm
LOS Assert PA -40 dBm
LOS De -Assert PD -25 dBm 2
                      LOS Hysteresis PA – PD 0.5 2 6 dB


  1. Measured with Light source 850nm, ER=9dB; BER =10 -12 @PRBS=223-1
  2. When LOS de-asserted, the RX data+/- output is signal output.

Pin out of Connector Block on Host Board:

PIN Descriptions:

Pin Symbol Name/Description Note
1 VEET Transmitter Ground (Common with Receiver Ground) 1
2 TFault Transmitter Fault
3 TDis Transmitter Disable. 2
4 MOD_DEF(2) Module Definition 2. Data line for Serial ID. 3
5 MOD_DEF(1) Module Definition 1. Clock line for Serial ID. 3
6 MOD_DEF(0) Module Definition 0. Grounded within the module. 3
7 Rate Select No connection required 4
8 LOS Loss of Signal indication. Logic 0 indicates normal operation 5
9 VEER Receiver Ground (Common with Transmitter Ground) 1
10 VEER Receiver Ground (Common with Transmitter Ground) 1
11 VEER 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 VEER Receiver Ground (Common with transmitter Ground) 1
15 VCCR Receiver power Supply
16 VCCT Transmitter Power supply
17 VEET 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 VEET Transmitter 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 3.46V.
  • Logic 0 indicates normal operation.
  • Logic 1 indicates loss of signal.

Mechanical Dimensions:

Recommend Circuit Schematic:

Regulatory Compliance:

Feature Reference Performance
Laser Eye Safety FDA 21CFR 1040.10, 1040.11 IEC/EN 60825-1,2 Class 1 laser product
Component Recognition IEC/EN 60950, UL Compatible with standards
ROHS 2002/95/EC Compatible with standards
Electrostatic discharge(ESD) IEC/EN 61000-4-2 Compatible with standards
EMC EN61000-3 Compatible with standards
Electromagnetic Interference(EMI) FCC Part 15 Class B EN 55022 Class B (CISPR 22A) Compatible with standards