In today’s world operational amplifier is used in lot of application. The techniques for achieving high slew rate and high CMRR is by cascading the transistors. This paper focus is on understanding of Operational Trans conductance Amplifier (OTA) and Current Differencing Trans conductance Amplifier (CDTA) with its application as Instrumentation Amplifier (IA) for Biomedical application. We have...

This paper proposes the use of sampled-data operation in op-amps. The technique favors very low supply voltage and micro-power. After discussing the method at a general level, a possible sampled-data scheme is analyzed. Simulations with a low threshold technology show that a 0.5-V supply is possible. A version of the circuit, which has been integrated by using a standard 0.18-μm CMOS technology...

Several possible implementations of variable-gain current conveyors are proposed. They can be designed with two opamps and current mirrors and exhibit constant bandwidth property. Their configuration as differential-output current amplifiers is straightforward.

Presented is a 0.9 V rail-to-rail constant gm CMOS amplifier input stage consisting of complementary differential pairs and a gm control circuit. The gm control circuit eliminates the gm dead zone, which occurs in the conventional rail-to-rail amplifier with ultra-low supply voltages. The proposed amplifier input stage has a constant gm that varies by +2.3% for rail-to-rail input common-mode le...

A numerical design method is presented for the design of all pole band pass active-RC filters applying just one operational amplifier. The operational amplifier model used is the integrator model: t/s where t is the unity gain frequency. The design method is used for the design of a fourth order band pass filter with Butterworth poles applying just one operational amplifier coupled as a unity g...

The transimpedance or current feedback operational amplifier (CFB op-amp) is reviewed and compared to a conventional voltage mode op-amp using an analysis emphasizing the basic feedback characteristics of the circuit. With this approach the paradox of the constant bandwidth obtained from CFB op-amps is explained. It is demonstrated in a simple manner that the constant gain-bandwidth product of ...

While in the process of reviewing Texas Instruments applications notes, including those from the recently acquired Burr-Brown – I uncovered a couple of treasures, this handbook on active RC networks and one on op amp applications. These old publications, from 1966 and 1963, respectively, are some of the finest works on op amp theory that I have ever seen. Nevertheless, they contain some materia...

The general utility of the operational amplifier is derived from the fact that it is intended for use in a feedback loop whose feedback properties determine the feed-forward characteristics of the amplifier and loop combination. To suit it for this usage, the ideal operational amplifier would have infinite input impedance, zero output impedance, infinite gain and an open-loop 3 dB point at infi...

Two simple voltage-controlled-oscillators (VCO) with linear tuning laws employing only a single current feedback operational amplifier (CFOA) in conjunction with two analog multipliers (AM) have been highlighted. The workability of the presented VCOs has been demonstrated by experimental results based upon AD844 type CFOAs and AD534 type AMs.

In 1969, the first triple operational transconductance amplifier or OTA was introduced. The wide acceptance of this new circuit concept prompted the development of the single, highly linear operational transconductance amplifier, the CA3080. Because of its extremely linear transconductance characteristics with respect to amplifier bias current, the CA3080 gained wide acceptance as a gain contro...