Wide input range, fully-differential indirect current feedback instrumentation amplifier for self-x sensory systems / Symmetrischer Instrumentierungsverstärker mit indirekter Stromgegenkopplung und hoher Eingangsignalspanne für integrierte Sensorsysteme mit Self-x-Eigenschaften

Abstract

Abstract This paper research presents the design of wide input range indirect current feedback-instrumentation amplifier (CFIA). In order to extend the input range without sacrificing the amplifier performance, the negative feedback is applied to the source coupled differential pairs inputs. The feedback network and the biasing current can be programmed to work at different values to meet different signal conditions or to self-correct the drift in the amplifier properties. The simulated input range Vin; P-P=1.6 V with total harmonic distortion of 0.93 % at 5 MHz frequency. Thus the proposed CFIA is very suitable to read the high speed and high common mode range TMR differential voltage sensor signal. The circuit is implemented using the CMOS 0.35 μm technology from Austriamicrosystems (AMS) and by using Cadence Virtuoso design tools.