Modified Ultra-Low Power Electronically Tunable Current Mode Instrumentation Amplifier For Biomedical Application

Abstract

In this paper, a proposed modified current mode instrumentation amplifier (CMIA) circuit has been designed, which can be used in low-power applications such as in biomedical domain. The instrumentation amplifier is in current mode, the circuit enjoys the advantage of electronic tunability. There is no need of a variable resistor to change the instrumentation amplifier gain, the gain can be changed electronically i.e. by changing either bias currents or bias voltages. All the simulations have been performed in cadence virtuoso at UMC-180nm technology. The proposed modified CMIA provides a differential gain in the range (29.97dB - 43dB), CMRR in the range (69.71dB - 71.05dB), power dissipation in the range (300.67nW - 371.16nW). The proposed modified CMIA also provides an improvement in CMRR of 52 with respect to CC-CMIA [4] and an improvement of 23.24 As an application example, this CMIA can be used in pacemakers, as it is capable enough to amplify ECG signals, and also to remove any power line interference noise or motion artifacts that affects the ECG signal. Also because of its low voltage-supply requirement and low power dissipation, it can find its application in low power devices.