1.25Gbps/2.5Gbps, +3V to +5.5V, Low-Noise Transimpedance Preamplifiers for LANs

The MAX3266 is a transimpedance preamplifier for 1.25Gbps LAN fiber optic receivers. The circuit features 200nA input-referred noise, 920MHz bandwidth, and 1mA input overload.

The MAX3267 provides a pin-for-pin compatible solution for communications up to 2.5Gbps. It features 500nA input-referred noise, 1.9GHz bandwidth, and 1mA input overload.

Both devices operate from a single +3.0V to +5.5V supply and require no compensation capacitor. They also include a space-saving filter connection that provides positive bias for the photodiode through a 1.5kΩ resistor to VCC. These features allow easy assembly into a TO-46 or TO-56 header with a photodiode.

The 1.25Gbps MAX3266 has a typical optical dynamic range of -24dBm to 0dBm in a shortwave (850nm)configuration or -27dBm to -3dBm in a longwave (1300nm) configuration. The 2.5Gbps MAX3267 has a typical optical dynamic range of -21dBm to 0dBm in a shortwave configuration or -24dBm to -3dBm in a longwave configuration.

Applications

* 1Gbps to 2.5Gbps Optical Receivers * Fibre Channel * Gigabit Ethernet

* 200nA Input-Referred Noise (MAX3266)

* 500nA Input-Referred Noise (MAX3267)

* 920MHz Bandwidth (MAX3266)

* 1900MHz Bandwidth (MAX3267)

* 1mA Input Overload

* Single +3.0V to +5.5V Supply Voltage