Abstract
Combining different biological data, such as electroencephalogram (EEG), electrocardiogram (ECG), and electromyography (EMG), could decipher elaborated hidden physiological mechanisms. As cyber-physical systems enter this multisignal era, novel, hybrid, and portable systems capable of measuring multiple different biological signals are progressively needed. This chapter describes the step-by-step design of an ExG platform, that is, a hybrid programmable apparatus for the acquisition of different biological signals in a synchronous and combined way. The chapter provides a detailed description of the design needs, decisions, and strategies that can easily be applied to other platforms. The system consists of eight channels programmed via selection inputs. Each channel is composed of a common input stage followed by three different paths (for EEG, ECG, EMG) addressable via demultiplexer, which complete the signal conditioning with filtering and additional amplification. The design of the platform utilizes entirely commercial components. The ExG system was validated through SPICE simulations using accurate models of the selected commercial components. Results showed that system performance includes a common-mode rejection ratio (CMRR) of 133.9dB, input resistance of 20GΩ, input common-mode range (ICMR) of (−0.7V, +1.7V), and power consumption of 451.1mW. The gain estimated for EEG, ECG, and EMG was respectively 87.95dB, 53.98dB, and 27.96dB. © 2025 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies.