QTIA, a 2.5 or 10 Gbps 4-Channel Array Optical Receiver ASIC in a 65 nm CMOS Technology

TL;DR

The paper presents QTIA, a 4-channel optical receiver ASIC in 65 nm CMOS technology, capable of 2.56 to 10 Gbps, with features for optimized photodiode matching and radiation mitigation.

Contribution

It introduces a configurable 4-channel optical receiver ASIC with advanced biasing and radiation mitigation features, tailored for high-speed optical communication.

Findings

Successfully tested with GaAs photodiodes in lab conditions.

Achieved configurable data rates between 2.56 Gbps and 10 Gbps.

Demonstrated compatibility with different photodiode types.

Abstract

The Quad transimpedance and limiting amplifier (QTIA) is a 4-channel array optical receiver ASIC, developed using a 65 nm CMOS process. It is configurable between the bit rate of 2.56 Gbps and 10 Gbps per channel. QTIA offers careful matching to both GaAs and InGaAs photodiodes. At this R&D stage, each channel has a different biasing scheme to the photodiode for optimal coupling. A charge pump is implemented in one channel to provide a higher reverse bias voltage, which is especially important to mitigate radiation effects on the photodiodes. The circuit functions of QTIA successfully passed the lab tests with GaAs photodiodes.