CMOS Bio-medical Amplifier based on Tera-Ohm Pseudo-resistor for Bio-detection System

Abstract

This work presents the design of a CMOS bio-medical amplifier using $\mathrm{T}\ \Omega$ pseudo-resistor based on MOS transistors operating in the weak inversion region. The pseudo-resistor is utilized as a feedback element in the first and second stage of the two-stages bio-medical amplifiers in the portable bio-detection system. Analytical analysis and simulations in LT-spice using 130 nm CMOS technology are performed to validate the realization of the extremely high resistance which can be reached to over tens of $\mathrm{T}\ \Omega$. The simulation of the two-stages bio-medical amplifier based pseudo-resistor are carried out in LT-spice using ± 0.6 V supply. The LT-spice simulation results are confirming with both the results obtained by the MATLAB and the analytical analysis of the pseudo-resistor.