A novel approach for high gain instrumentation amplifier in ΔΣ ADC

Abstract

The power consumption, area on chip and signal accuracy plays a vital role in designing any sensor system. The output of the sensor system is often weak differential signals along with unwanted signals. The Instrumentation amplifier which has good CMRR amplifies the weak signals by eliminating the common mode voltages and has low power consumption. This paper proposes a new method for ultra-low power consumption. It explores the designing of Instrumentation amplifier based on Differential Difference Amplifier in Sigma Delta converter. The non-tailed bulk driven differential pairs circuits with positive feedback in Instrumentation amplifier has been used for ultra-low power consumption. The Instrumentation amplifier as an input structure for sigma delta convertor exhibits high input impedance and linearity. These properties made the direct use of sensor elements on converters without use of front end circuitry. The proposed work is simulated by using 180 nm CMOS process and the results will be compared with the conventional methods.