A Sub-1muA Low-PowerLow-NoiseAmplifier with Tunable Gain and Bandwidth for EMG and EOG Biopotential Signals

Inhalt:
This paper presents the design of a low-power low-noise amplifier for biomedical and healthcare applications, focusing on electromyography and electrooculography. The signals operate in different broad bands, yet follow an impulse-shape transmission, being suitable to be applied and detected by the same receiver. The biopotential sensing amplifiers usually have a major impact in power and noise performance of an analog front end; hence, the development of a low-noise amplifier with low-power consumption is of great importance. In this paper, the state-of-the-art amplifiers for biomedical applications are overviewed, and the proposed solution is presented. The proposed design has tunable cutoff frequency (FC) and gain, being adjustable for each type of signal. The circuit is designed in UMC 130 nm CMOS technology, supplied by 1.2 V, and consumes less than 1 muA. Post-layout simulation results show that, at the high FC of 2 kHz, the gain is 34 dB, presenting an input-referred noise of 1.476 muVrms corresponding to a noise efficiency factor (NEF) of 1.27. Whereas at the low FC of 20.91 Hz, the gain is 52.35 dB, the input-referred noise is 0.202 muVrms, and the NEF is 1.70.