Computer symbolic analysis and study of the signal characteristics of a microwave integrated transimpedance amplifier based on CMOS-transistors

Authors: Koryakovtsev A. S., Babak L. I., Kokolov A. A.

Annotation: A technique is proposed for investigating and designing microwave transimpedance amplifiers (TIAs) based on the joint use of computer symbolic analysis and CMOS-transistors' linear equivalent circuits (ECs). The technique makes it possible to analyze the influence of various schematic parameters on TIA performances using automatically generated analytical expressions as well as to obtain recommendations for amplifier design. The investigation of the influence of devices' EC elements helps to choose CMOS-transistors' constructions and sizes when designing integrated TIAs. The approach proposed is applied to the input stage of microwave common source-common drain TIA with parallel feedback. The analysis of dependences of the main TIA characteristics (transimpedance, group delay, and input/output impedances) on circuit elements and transistor parameters is performed. Also, the amplifier stability is investigated. It is shown that, in contrast to the commonly used TIA analysis based on idealized models of active elements, the proposed approach provides sufficient accuracy in calculating amplifier performances up to the frequency of 30 GHz

Keywords: transimpedance amplifier, microwaves, ic, cmos-transistor, linear equivalent circuit, symbolic analysis, computer algebra