A 50 Gb/s Rad-Hard Quad TIA IC for Onboard Satellite Interconnects

Energy efficiency is one of the most important factors while designing integrated circuits for space applications. At the same time, an IC must operate correctly despite of harsh space environment. This paper demonstrates a quad channel transimpedance amplifier (TIA) integrated circuit that aims to simultaneously achieve high data rates, radiation hardening, and high energy efficiency. To optimize TIA operation with respect to bandwidth, gain, power consumption, we implemented a digital controlling interface driving low speed DACs for adjusting currents in different TIA stages. The complete circuit has been manufactured in a 130 nm SiGe BiCMOS semiconductor process. Electrical probe testing shows the achievable data rate of more than 50 Gb/s in each channel. The implemented on-chip low dropout regulators provide an operation from a single supply voltage. The TIA IC was exposed to proton and gamma radiation. At a 2.5 V supply voltage the minimum power efficiency of 1.35 pJ/bit is demonstrated.