High-Sensitivity Transimpedance Amplifier

The PHY1095 is a transimpedance amplifier designed for use within small form factor fiber optic modules targeted at gigabit-enabled passive optical network (GEPON) applications. Working from a 3.3V power supply, the PHY1095 integrates a low-noise transimpedance amplifier, with a typical differential transimpedance of 50kΩ, an AGC, and an output stage. An output is also provided that can be used to implement a signal strength monitor circuit. This is designed to sink or source a current equal to the photodiode current for ease of interfacing. Sensitivity of -32dBm can be achieved at 1.25Gbps using a photodiode with 0.5pF capacitance and a responsivity of 0.8A/W at a wavelength of 1490nm. The PHY1095 is available in die form for mounting on a header to create a ROSA when combined with suitable optics and photo-detector diode.

Applications

* GEPON Optical Network Unit (ONU) * Gigabit Ethernet

* -32dBm Sensitivity

* Up to 1.25Gbps (NRZ) Data Rates

* 60nA RMS Typical Input Referred Noise

* Automatic Gain Control

* Flexible Bond Pad Layout and Output Signal Inversion for Simple ROSA Layout

* Received-Signal Strength Indicator Output with Selectable Direction of Current Flow

* -40°C to +85°C Operating Temperature Range