A 2.5-Gb/s CMOS optical receiver with wide dynamic range using dual AGCs

Abstract

A 2.5-Gb/s optical receiver with wide dynamic range has been developed in a 55-nm standard CMOS technology. As the input stage of the proposed optical receiver, a transimpedance amplifier of a three-cascaded inverting topology with a feedback resistor incorporates dual automatic gain controls to broaden the input dynamic range. Followed by a post amplifier and a 50-Ω output buffer, the measured input sensitivity, overload, and dynamic range of the optical receiver are respectively − 26 dBm, 3 dBm, and 29 dB for a bit-error rate of 10−12 at 2.5 Gb/s. The whole receiver draws a total current of 36 mA from a 3.3 V supply and the chip has an area of 1176 μm × 985 μm.