Low Voltage and Low Power AC Coupled Instrumentation Amplifier

Biological signals from the human body range from a few hundred microvolts (μV) to a few millivolts (mV), making accurate reading difficult, especially when they are measured in a noisy environment. In this work, the design of a low voltage and low power OPAMP and Instrumentation Amplifier (AI) for biomedical applications are presented. As an example, a signal from an electrocardiogram is amplified, verifying the good performance of the designed circuit. Important features of the designed AI are: reduced power rails (±0.4V), low power consumption (309nW), and high immunity to common-mode noise (CMRR=82dB), in a silicon area of 320μm X 200μm. The proposed AI is suitable for applications in wearable and implantable systems. The IA was manufactured in a 0.18μm TSMC technology.