Abstract
Bioelectric signals play a vital role in human healthcare monitoring. This review examines front-end circuits and systems for acquiring electroencephalogram (EEG), electrocorticogram (ECoG), electrocardiogram (ECG), electrooculogram (EOG), and electromyogram (EMG) signals, highlighting key design considerations and challenges. This work further surveys related state-of-the-art biosensors, commercial components, and wearable consumer products, and offers insights into emerging research directions in biosensor circuit design for next-generation healthcare applications.