CCII+ Cell Based Instrumentation Amplifier Using BD-CM Gain Enhanced OTA

Abstract

This paper presents the design of an instrumentation amplifier (IA) using second generation positive current conveyor which uses gain enhanced, bulk-driven, balanced current mirror, operational transconductance amplifier (OTA) cascaded with two CMOS inverters. First of all, a CMOS, bulk-driven current mirror OTA is designed and simulated in 180nm technology. For its performance enhancement, besides the current mirror topology, this OTA utilized the current starving technique which apply partial positive feedback (PPF) in active load side of OTA. Secondly, the conversion of this bulk-driven OTA into CCII plus cell is performed using inverters to yield its X and Z nodes. Finally, this CCII plus cell is used to design the IA. The gain of IA in differential input and single ended output configuration can be varied in the range of 10dB to 75dB. The various performance parameters of IA are simulated using Tanner EDA tool of 16.1 version in standard n-tub 180nm CMOS process technology node.

Keywords: Bulk driven, Operational Transconductance Amplifier, Partial Positive Feedback, Current conveyor, Instrumentation Amplifier