GAOTek SFP CWDM Transceiver SFPCW-106, 4.25Mb/s and 40km

This 4.25 Gbps SFP CWDM transceiver is used with Single-mode fiber to span up to 24.8 Miles (40Km) transmission distance


Key Features

  • Up to 24.8 Miles(40km) on 9/125µm SMF
  • Up to 4.25Gb/s data links
  • Compliant with SFF-8472
  • DFB laser transmitter and PIN photo-detector
  • Hot-pluggable SFP footprint
  • Duplex LC/UPC type pluggable optical interface
  • Low power dissipation
  • Metal enclosure, for lower EMI
  • RoHS compliant and lead-free
  • Support Digital Diagnostic Monitoring interface
  • Case operating temperature range from 32°F to 158°F (0°C to +70°C)
  • Single +3.3V power supply



Technical Specifications

Protocol 2-wire serial communication protocol
Standard SFF-8472
Working Range Up to 24.8 Miles(40 Km)
Data rate 4.25 Gb/s
Wavelength CWDM
Transmitter Extinction Ratio 6 dB
Transmitter Off Output Power -45dBm
Transmitter Differential Line Input Impedance 90-110 Ω
Receiver Sensitivity -20dBm
Receiver Input Optical Wavelength 1270-1610nm
Receiver Input Saturation Power(Overload) 0 dBm
Supply Voltage -0.5 to 4V
Dimensions 2.29in*0.54in*0.33 in                                    (L  58.4mm*W 13.9mm*H 8.5mm)
Relative Humidity 5% to 95%
Storage Temperature -40°F to 185°F (-40°C to 85°C)
Case Operating Temperature 32°F to +158°F (0°C to 70°C)




Product Selection

Wavelength Clasp Color code
1270 nm Gray
1290 nm Gray
1310 nm Gray
1330 nm Purple
1350 nm Blue
1370 nm Green
1390 nm Yellow
1410 nm Orange
1430 nm Red
1450 nm Brown
1470 nm Gray
1490 nm Purple
1510 nm Blue
1530 nm Green
1550 nm Yellow
1570 nm Orange
1590 nm Red
1610 nm Brown

PIN Descriptions:


  1. Circuit ground is internally isolated from chassis ground.
  2. Laser output disabled on TDIS >2.0V or open, enabled on TDIS <0.8V
  3. Should be pulled up with 4.7k – 10kohms on host board to a voltage between 2.0V and 3.6V.MOD_DEF (0) pulls line low to indicate 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. LOS is open collector output should be pulled up with 4.7k – 10kohms on host board to a voltage between 2.0V and 3.6V. Logic 0 indicates normal operation; logic 1 indicates loss of signal.

Electrical Interface Characteristics:

Note (1): A (TX) + B (RX) = 300mA (Not include termination circuit)

Digital Diagnostic Functions

GAOTek GAO-SFPCW-106 transceivers support the 2-wire serial communication protocol as defined in the SFP MSA. It is very closely related to the E2PROM defined in the GBIC standard, with the same electrical specifications. The standard SFP serial ID provides access to identification information that describes the transceiver’s capabilities, standard interfaces, manufacturer, and other information.

Additionally, GAOTek SFP transceivers provide a unique enhanced digital diagnostic monitoring interface, which allows real-time access to device operating parameters such as transceiver temperature, laser bias current, transmitted optical power, received optical power and transceiver supply voltage .It also defines a sophisticated system of alarm and warning flags, which alerts end-users when particular operating parameters are outside of a factory set normal range.

The SFP MSA defines a 256-byte memory map in E2PROM that is accessible over a 2-wire serial interface at the 8 bit address 1010000X (A0h). The digital diagnostic monitoring interface makes use of the 8 bit address 1010001X (A2h), so the originally defined serial ID memory map remains unchanged. 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. When the serial protocol is activated, the serial clock signal (SCL, Mod Def 1) is generated by the host. The positive edge clocks data into the SFP transceiver into those segments of the E2PROM that are not write-protected. The negative edge clocks data from the SFP transceiver. The serial data signal (SDA, Mod Def 2) is bi-directional for serial data transfer. The host uses SDA in conjunction with SCL to mark the start and end of serial protocol activation. The memories are organized as a series of 8-bit data words that can be addressed individually or sequentially.

Digital diagnostics for the GAO-SFPCW-106 are internally calibrated by default.

Recommended Circuit Schematic

Regulatory Compliance

Mechanical Specifications


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


Content missing