LNA Architectures for ECG Analog Front End in CMOS Technology Malti Bansal and Ishita Sagar Abstract A low noise amplifier, usually abbreviated as LNA, plays a crucial role in the collection of ECG signals for further processing. Through the course of this paper, the numerous topologies of LNA have been thoroughly studied and reviewed. These topologies have been further compared to narrow down the best among them, based on parameters expected from an ideal LNA. According to our analysis, open-loop OTA topology is the best suited LNA topology according to all design parameters taken under consideration for its use in ECG analog front end applications. Keywords LNA · OTA · ECG · AFE · CMOS 1 Introduction The rates of diseases and disorders of the human heart are increasing since the past few years, owing to the hectic lifestyles of humans. The heart is the most vital organ for the human body, any disease related to it needs to be identified and cured at the earliest. The first step towards identifying any disease related to the heart is measuring its activity, which is thereby done in the form of electric signals, known as ECG signals. In earlier days, this measurement presented the need for substantial equipment but owing to rapid advancements in the electronics industry, the same equipment has reduced vastly in size. It has also been known to improve in terms of performance. Such considerable achievements, especially in terms of performance, in this field, are a result of the wide use of Low Noise Amplifier (LNA). LNA is one of the many components present in the Analog Front End (AFE) of an ECG acquisition/collection system. The AFE helps in the proper conditioning of a signal once acquired from the external environment. In this paper, different topologies and configurations adopted for LNA in ECG Applications have been reviewed. A M. Bansal (B ) · I. Sagar Department of Electronics and Communication Engineering, Delhi Technological University (DTU), Delhi 110042, India e-mail: maltibansal@gmail.com © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021 G. Ranganathan et al. (eds.), Inventive Communication and Computational Technologies, Lecture Notes in Networks and Systems 145, https://doi.org/10.1007/978-981-15-7345-3_83 973