GAOTek Copper SFP Transceiver CUSFP-101, 1.25Gb, 10/100/1000BASE-T, Link

This 1.25 Gbps 10/100/1000 BASE-T Copper SFP transceiver is used to span up to 1.2 Miles (2 Km) transmission distance


Key Features

  • Up to 1.25 Gb/s bi-directional data links
  • 25 Gigabit Ethernet over Cat 5 cable
  • 10/100/1000 BASE-T operation in host systems with SGMII interface
  • Compact RJ-45 connector assembly
  • Hot-pluggable SFP footprint
  • Low power dissipation(1.05W typical)
  • Fully metal enclosure, for lower EMI
  • RoHS compliant and lead-free
  • Single +3.3V power supply
  • Case operating temperature range from:

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)



Technical Specifications

Protocol 2 Wire Serial Communication
Standard IEEE Std 802.3

1000BASE-X auto-negotiation


Working Range Up to  1.2 Miles (2Km)
Data rate 1.25 Gb/s
Line Frequency 125 MHz
Cable Length 100 m
Supply Current 375 mA
Dimensions 2.28in*0.52in*0.5 in

(L  58mm*W 13.4mm*H 15mm)

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)



PIN Descriptions:


  1. Circuit ground is connected to chassis ground
  2. PHY disabled on TDIS > 2.0V or open, enabled on TDIS < 0.8V
  3. Should be pulled up with 4.7k – 10k Ohms on host board to a voltage between 2.0 V and 3.6 V. MOD_DEF (0) pulls line low to indicate module is plugged in.
  4. LVTTL compatible with a maximum voltage of 2.5V. Not supported on GAO-CUSFP-101.

General Specifications


  1. Clock tolerance is +/- 50 ppm
  2. By default, the GAO-CUSFP-101 is a full duplex device in preferred master mode
  3. Automatic crossover detection is enabled. External crossover cable is not required.
  4. 10/100/1000 BASE-T operation requires the host system to have an SGMII interface with no clocks.

Electrical Power Interface:

The GAO-CUSFP-101 has an input voltage range of 3.3 V +/- 5%. The 4V maximum voltage is not allowed for continuous operation.

Note (1): Power consumption and surge current are higher than the specified values in the SFP MSA.

Low Speed Signals

MOD_DEF (1) (SCL) and MOD_DEF (2) (SDA) are open drain CMOS signals (see  “Serial Communication Protocol”). Both MOD_DEF (1) and MOD_DEF (2) must be pulled up to host_Vcc.

Serial Communication Protocol

GAO-CUSFP-101 supports the 2-wire serial communication protocol outlined in the SFP MSA. It uses an Atmel AT24C02B 256 byte EEPROM with an address of A0h.

High Speed Electrical Interface

All high-speed signals are AC-coupled internally.

Mechanical Specifications



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