GAOTek XFP DWDM Transceiver with 8.5Gb/s

This 8.5 Gigabit XFP DWDM Transceiver is used with single mode optical fiber to reach up to 24.85 miles (40km) transmission distance.



This 8.5 Gigabit XFP DWDM Transceiver is used with single mode optical fiber to reach up to 24.85 miles (40km) transmission distance. It is designed for serial optical data communications such as 8G Fiber Channel. This transceiver supports the C-band wavelength .It has a Cooled DWDM EML type transceiver and PIN type receiver integrated with a trans-impedance preamplifier (TIA) and signal conditioner. This Dense Wavelength Division Multiplexing small form-factor pluggable (XFP DWDM) transceiver provides built-in Digital Diagnostics Functions. It complies with 8G Fiber channel and RoHS lead free standards.


Key Features:

  • Up to 24.85 miles (40km) transmission distance.
  • Cooled DWDM EML and PIN Receiver
  • Supports 8.5Gb/s Data link.
  • Supports the C-band wavelength range between 1528.77nm to 1567.13nm
  • Hot-pluggable XFP footprint
  • Supports Line-side and XFI loopback
  • RoHS-6 Compliant (lead-free)
  • Power dissipation <3.5W
  • Single 3.3 V power supply.
  • Compliance with Fiber Channel FC-PI-4 800-SM-LL-L
  • Full Duplex LC connector
  • No Reference Clock required
  • Built-in digital diagnostic functions
  • AC/AC Coupling according to MSA
  • Case operating temperature range from 23 °F to 158 °F (-5°C to 70°C)

Technical Specifications:

Working Range Up to 24.85 miles (40km)
Standards 8G Fiber Channel


RoHS-6 compliant.

Memory 256 byte EEPROM
Data rate 8.5Gb/s
Wavelength range 1528.77nm to 1567.13nm
Connector LC
Transmitter DWDM EML
Receiver PIN
Transmitter output optical Power 0 dBm to 4 dBm
Fiber type 9/125 mm single-mode
Receiver Sensitivity -16.5 dBm
Receiver Input Saturation Power 0.5 dBm
Supply Voltage 3.3 V
Maximum Power Consumption <3.5 W
Transmitter Input Differential Impedance 100Ω
Dimensions 3.07in x 0.72in x 0.45in (L 78mm x W18.3mm x   H 11.4mm)
Relative Humidity 5% to 95%
Storage Temperature -40 °F to 185 °F (-40°C to 85°C)
Case Operating Temperature 23 °F to 158 °F (-5°C to 70°C)

Additional Information:


Ideal to be used on applications such as

  • Multi-rate 8x/4x/2x Fiber Channel

Order Information:

Product ID Media Wavelength


Transmission Distance Temperature Range


single-mode fiber Refer to wavelength selection 24.85 miles (40km)   23 °F to 158 °F (-5°C to 70°C)


Wavelength Selection:

C-band λc Wavelength Guide Pin Descriptions

Channel Wavelength(nm) Frequency(THZ) Channel Wavelength(nm) Frequency(THZ)
C13 1567.13 191.30 C37 1547.72 193.70
C14 1566.31 191.40 C38 1546.92 193.80
C15 1565.50 191.50 C39 1546.12 193.90
C16 1564.68 191.60 C40 1545.32 194.00
C17 1563.86 191.70 C41 1544.53 194.10
C18 1563.05 191.80 C42 1543.73 194.20
C19 1562.23 191.90 C43 1542.94 194.30
C20 1561.42 192.00 C44 1542.14 194.40
C21 1560.61 192.10 C45 1541.35 194.50
C22 1559.79 192.20 C46 1540.56 194.60
C23 1558.98 192.30 C47 1539.77 194.70
C24 1558.17 192.40 C48 1538.98 194.80
C25 1557.36 192.50 C49 1538.19 194.90
C26 1556.55 192.60 C50 1537.40 195.00
C27 1555.75 192.70 C51 1536.61 195.10
C28 1554.94 192.80 C52 1535.82 195.20
C29 1554.13 192.90 C53 1535.04 195.30
C30 1553.33 193.00 C54 1534.25 195.40
C31 1552.52 193.10 C55 1533.47 195.50
C32 1551.72 193.20 C56 1532.68 195.60
C33 1550.92 193.30 C57 1531.90 195.70
C34 1550.12 193.40 C58 1531.12 195.80
C35 1549.32 193.50 C59 1530.33 195.90
C36 1548.51 193.60 C60 1529.55 196.00
Non-ITU Peak wavelength between 1528.77nm-1567.13 C61 1528.77 196.10

Digital Diagnostics Functions:

  • GAOTek GAO- XFPDW -104 transceiver support the 2-wire serial communication protocol as defined in the XFP MSA.
  • Additionally, GAOTek XFP 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 XFP Serial id provides access to identification information that describes the transceiver’s capabilities, standard interfaces, manufacturer and other information.
  • XFP 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 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.

General Specifications:

Parameter Symbol Min Type Max Unit Note
Bit Rate BR   8.5 Gb/s  
Bit Error Ratio BER     10-12   1
Maximum Supported Distances       40 km  


  1. Tested with a 2 31 – 1 PRBS

Electrical characteristics:

Parameter Symbol Min Type Max Unit Note
Module Total Power       3.5 W 1
Input Differential Impedance Rin 100 2
Single ended data input swing Vin, pp 120 820 mV
Transmit Disable Voltage VD 2.0 Vcc V 3
Transmit Enable Voltage Ven GND GND+ 0.8 V
Transmit Disable Assert Time 10 us
Differential data output swing Vout,pp 340 650 850 mV 4
Data output rise time tr 38 ps 5
Data output fall time tf 38 ps 5
LOS Fault VLOS fault Vcc–0.5 VccHOST V 6
LOS Normal VLOS norm GND GND+0.5 V 6
Power Supply Rejection PSR 7


  1. Maximum total power value is specified across the full temperature and voltage range
  2. After internal AC coupling
  3. Open circuit
  4. Into 100 ohms differential termination
  5. These are unfiltered 20-80% values
  6. Loss of Signal is open collector to be pulled up with a 4.7kΩ – 10kΩ resistor to 3.15 – 3.6V
  • Logic 0 indicates normal operation.
  • Logic 1 indicates no signal detected.
  1. As per the XFP MSA Specification 1.

Optical Characteristics:

Parameter Symbol Min Type Max Unit
Average Optical  Power PAVE 0 4 dBm
Optical Wavelength λ λc -100 λc -100 nm
Optical Extinction Ratio ER 8.2 dB
Average Launch power of transmitter POFF -30 dBm
Side mode Suppression ratio SMSR 30 dB
Tx Jitter Generation(peak-to-peak) Jp-p 0.1 UI
Transmitter and Dispersion Penalty TDP 2 dB
Relative Intensity Noise RIN -130 dB/Hz
Receiver Sensitivity PSEN -16.5 dBm
Wavelength Range λC 1260 1600 nm
Input Saturation Power (Overload) Psat 0.5 dBm
Receiver Reflectance Rrx -27 dB
LOS Assert LOSA -28 dBm
LOS De -Assert LOSD -22 dBm
LOS Hysteresis 0.5 dB

PIN Diagram:

PIN Descriptions:

Pin Logic Symbol Name/Description Note
1 GND Module Ground 1
2 VEE5 Optional –5.2 Power Supply – Not required
3 LVTTL-I Mod-Desel Module De-select; When held low allows the module to respond to 2-wire serial interface commands
4 LVTTL-O Interrupt Interrupt (bar); Indicates presence of an important condition which can be read over the serial 2-wire interface 3
5 LVTTL-I TX_DIS Transmitter Disable; Transmitter laser source turned off
6 VCC5 +5 Power Supply
7 GND Module Ground 1
8 VCC3 +3.3V Power Supply
9 VCC3 +3.3V Power Supply
10 LVTTL-I SCL Serial 2-wire interface clock
11 LVTTL-I/O SDA Serial 2-wire interface data line 3
12 LVTTL-O Mod_Abs Module Absent; Indicates module is not present. Grounded in the module. 3
13 LVTTL-O Mod_NR Module Not Ready; GAOTek defines it as a logical OR between RX_LOS and Loss of Lock in TX/RX. 3
14 LVTTL-O RX_LOS Receiver Loss of Signal indicator 3
15 GND Module Ground 1
16 GND Module Ground 1
17 CML-O RD- Receiver inverted data output
18 CML-O RD+ Receiver non-inverted data output
19 GND Module Ground 1
20 VCC2 +1.8V Power Supply – Not required
21 LVTTL-I P_Down/RST Power Down; When high, places the module in the low power stand-by mode and on the falling edge of P_Down initiates a module reset


Reset; The falling edge initiates a complete reset of the module including the 2-wire serial interface, equivalent to a power cycle.
22 VCC2 +1.8V Power Supply – Not required
23 GND Module Ground 1
24 PECL-I RefCLK Reference Clock non-inverted input, AC coupled on the host board –Not required 2
25 PECL-I RefCLK- Reference Clock inverted input, AC coupled on the host board – Not required 2
26 GND Module Ground 1
27 GND Module Ground 1
28 CML-I TD- Transmitter inverted data input
29 CML-I TD+ Transmitter non-inverted data input
30 GND Module Ground 1


  1. Module circuit ground is isolated from module chassis ground within the module.
  2. A Reference Clock input is not required .If present, it will be ignored.
  3. Open collector; should be pulled up with 4.7kΩ – 10kΩ on host board to a voltage between 3.15V and 3.6V

PCB Layout and Bezel Recommendations:

XFP Host Board Mechanical Layout (dimensions are in mm)

Mechanical Specifications:

GAOTek’s XFP transceivers are compliant with the dimensions defined by the XFP Multi-Sourcing Agreement (MSA).

XFP transceiver (dimensions are in mm)

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