High-performance current-mode instrumentation amplifier circuit

Nand

IET Circuits, Devices & Systems

2016

This paper proposes two generalised instrumentation amplifier topologies which can operate in voltage, current, transadmittance, and transimpedance mode. Each topology is a two stage structure, wherein an amplifier is used as first stage in the first topology and a converter is employed in the second one. The second stage is difference amplifier for both the structures. The theoretical proposition is verified through operational floating current conveyor (OFCC). The effect of non-idealities of OFCC on system performance, in particular finite transimpedance and tracking error, is also analysed and corresponding mathematical formulation is presented. The functional verification is performed through SPICE simulation using CMOS-based implementation of OFCC. The experimental results using current feedback operational amplifier-based OFCC implementation are also included which are in close agreement with theoretical and simulated results.

Section: Introductionmentioning

confidence: 99%

Generalised operational floating current conveyor based instrumentation amplifier

Nand

IET Circuits, Devices & Systems

2016

2008 International Symposium on Intelligent Signal Processing and Communications Systems

“…However, in present, the voltage-mode circuits are still used in some applications. Several reported instrumentation amplifiers employed different building blocks such as operational transconductance amplifiers (OTAs) [17], current feedback amplifiers (CFAs) [18], current conveyors [19][20], operational conveyor [21], and operational floating current conveyor [22]. However, they employed many active building blocks, more than 2 active elements.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, passive elements, especially resistor need to be used in these circuits. Some of the mentioned circuits need to employ matched resistors [17][18]21], this degrades the CMRR of the instrumentation amplifiers.…”

Section: Introductionmentioning

confidence: 99%

An electronically controllable instrumentation amplifier based on CCCCTAs

Chanapromma

Tanaphatsiri

Siripruchyanun

2009

This article describes an instrumentation amplifier circuit by using current controlled current conveyors transconductance amplifiers (CCCCTAs). The circuit provides high input impedance which is a desirable feature for instrumentation amplifier. The proposed circuit can also be electronically adjustable gain and using only active components. Furthermore, the circuit enables to operate with the low temperature-sensitive. Consequently, the proposed circuit is very suitable for further fabricating into integrated circuit (IC) form to employ in a sensitive environment system. Moreover, the proposed circuit can provide in both output voltage and current signals. Performances of the proposed circuit are confirmed through PSPICE simulation results, they are in accordant to theoretical explanations.

International Journal of Applied Mathematics, Electronics and Computers

“…In the proposed scenario, desired gain is possible by adjusting the R3 and R4 resistances if R1 and R2 are internally adjusted to a constant value in Fig. 2 and using (6). DC servo loop can also be de-activated by connecting Y3 input to GND.…”

Section: Internal Building Blocksmentioning

confidence: 99%

“…Although CMIA in Fig. 1 gives good performance without resistor matching requirements, improved configurations are proposed utilizing both outputs of the current conveyors [2,[5][6][7]. In this paper, two of the CCII+ elements with high input common-mode range with high output swing close to rail-to-rail swing is employed at the input stage.…”

Section: Introductionmentioning

confidence: 99%

Current-Mode Rail-to Rail Instrumentation Amplifier for General Purpose Instrumentation Applications

Cini

2016

Instrumentation amplifiers are used extensively in bio-potential reading, industrial sensor applications, Wheatstone bridge amplifiers etc. In this work, a high input common-mode range instrumentation amplifier is presented. The amplifier is composed of two second generation current conveyors (CCII+) with common-mode input range close to supply swings and a differential difference current conveyor (DDCC) at the second stage with high voltage swing at the output. Also an optional DC servo loop is employed as a feedback to second stage for the removal of any possible DC offset voltage at the output which can be used for AC coupled applications. The simple design strategy with high input common-mode range and nearly rail-to-rail output stage together with increased bandwidth advantage of current-mode approach makes the proposed implementation desirable for many of the general purpose instrumentation applications. The design is made using 0.35μm AMS technology with 3V supply voltage. The operation is verified by HSPICE simulations.