A New Proposal for OFCC-based Instrumentation Amplifier

Abstract

This contribution puts forward a new voltage mode instrumentation amplifier (VMIA) based on operational floating current conveyor (OFCC). It presents high impedance at input terminals and provides output at low impedance making the proposal ideal for voltage mode operation. The proposed VMIA architecture has two stages - the first stage comprises of two OFCCs to sense input voltages and coverts the voltage difference to current while the second stage has single OFCC that converts the current to voltage. In addition it employs two resistors to provide gain and imposes no condition on the values of resistors. The behavior of the proposed structure is also analyzed for OFCC non idealities namely finite transimpedance and tracking error. The proposal is verified through SPICE simulations using CMOS based schematic of OFCC. Experimental results, by bread boarding it using commercially available IC AD844, are also included.

Single EX-CCCII based electronically tunable current mode instrumentation amplifier

“…Therefore, current mode IA is preferred over voltage mode IA. The IAs reported in [7][8][9][10][11][12][13]15,17,20,23,24,28,30] do not operate in the current mode. The electronically tunable property is absent in IAs described in [7, 9-11, 15-17, 20, 28-30].…”

“…With the advancement in the current mode design approach, many current mode active building blocks are introduced in the literature . Some of the mostly used active blocks are Second Generation Current Conveyor (CCII) [7,23,29], Current Controlled Current Conveyor (CCCII) [8,13,14], Differential Voltage Current Conveyor (DVCC) [9,24], Differential Difference Current Conveyor (DDCC) [10,30], Operational Floating Current Conveyor (OFCC) [11,15,16,28], Operational Trans-resistance Amplifier (OTRA) [12], Flipped Voltage Follower (FVF) [17], Current Operational Amplifier (COA) [18,19], Current Mirror [20], Current Differencing Trans-resistance Amplifier (CDTRA) [21], Current Follower Differential Input Transconductance Amplifier (CFDITA) [22], Extra-X Current Controlled Current Conveyor (EX-CCCII) [25],…”