Op amp

This paper on "Smart Irrigation System" is develop to create an automated irrigation mechanism which turns the pumping motor ON and OFF on detecting the moisture content of the earth using the soil moisture sensor without the intervention of human. The benefit of employing these techniques is to decrease human interference and it is quite feasible and affordable. This Smart irrigation system project is using an arduino micro-controller, that is programmed to collect the input signal according to moisture content of the soil and its output is given to the op-amp that will operate the pump.

Operational Amplifier (Op Amp) is a three terminal electronic device which has two inputs of high impedance. The first input is called inverting (represented by ‘-‘), and the other terminal is called non-inverting input. The third terminal serves as output port, where signal is usually amplified by some gain (A), depending on the nature of op amp and input characteristics. 
In this lab session we build op amp circuits and carry out various calculations of op amp characteristics. At the end of this lab, we are to strengthen theoretical knowledge by gaining hands on experience. This lab covers:
- Inverting Amplifiers 
- Non-inverting Amplifiers 
- Summing Amplifiers

The design of a linear integrated Op Amp circuit as an alternative solution to differential equation model of RLC Circuit is presented. The fundamental assumption used in the cascaded Operational Amplifier (Op Amp) design is that Op Amp acts linearly. In this paper, we will examine the behavior of the Op Amp when it is used in the cascaded circuit that is an electrical analog to the differential equation model of RLC circuit, which arises in numerous applications particularly in control and communication systems such as ringing circuits, resonant circuits, filters and oscillators. We will design the cascaded op amp circuit that is analog to differential equation model of RLC circuit and obtain graphical results of output function versus time using PSpice Software Probe. To confirm the validity of the design of a linear integrated Op Amp circuit as an alternative solution to differential equation model of RLC circuit implemented in the PSpice Software, simulation results are compared with RLC circuit where we find good agreement between the theoretical predictions of the differential equation model of RLC circuit and the design of a linear integrated Op Amp circuit.

Penguat Instrumasi Menggunakan Op Amp, Penguat Transkonduktansi, Penguat Logaritmik, Rangkaian Sumber Arus Konstan Menggunakan Penguat Operasional, Rangkaian Pengubah Arus Ke Tegangan, Rangkaian Detektor Puncak, dan Rangkaian Control Lampu Dimmer

This paper describes about different types of voltage followers. Each follower has its own advantages and limitations. The voltage follower can be characterized with current mirror source current or it can be used as a ideal current source. Voltage Follower is one of the most important analog circuits required in many analog integrated circuits. Input impedance of op amp is very high, giving effective isolation of the output from the signal source.

In design of analog circuits not only the gain and speed are important but power dissipation, supply voltage, linearity, noise and maximum voltage swing are also important. Noise limits the minimum signal level that a circuit can process with acceptable quality. Today analog designers constantly deal with the problem of noise because it trades with power dissipation, speed, and linearity.  So in this paper a biquad GIC notch filter is design which provides low noise linearity. In this research, the design and VLSI implementation of active analog filter, based on the Generalized Impedance Converter (GIC) circuit, are presented. The analog features include the filter type (band pass, high pass, low pass or notch), the centre or cut off frequency, and the quality factor. The circuit is then modeled and simulated using the Cadence Design Tools software package. Active filters are implemented using a combination of passive and active (amplifying) components, and require an outside power source. Operational amplifiers are frequently used in active filter designs. These can have high Q factor, and can achieve resonance without the use of inductors.  This paper presents a new biquad GIC notch filter topology for image rejection in heterodyne receivers and Front End receiver applications. The circuit contains two op-amp, resistors, and capacitor topology for testing purposes. It is implemented with standard CMOS 0.18μm technology. The circuit consumes 0.54 mW of power with a open loop gain 0dB, 1 dB compression point the linear gain obtained +7.5dBm at 1.1 kHz and 105 degree phase response , from a 1.8V power supply optimum.

VLC is a complex system with lots of challenges in its implementation. One of its problems is noise that originated from internal and external sources (sunlight, artificial light, etc). Internal noise is originated from active components of analog front-end (AFE) circuit, which will be discussed in this paper, especially on the trans-impedance amplifier (TIA) domain. The noise characteristics of AFE circuit in VLC system has been analyzed using the variety of available commercial Op Amp and different types of the photodiode (Si, Si-PIN, Si APD). The approach of this research is based on analytical calculus and simulation using MATLAB®. The results of this research show that the main factor that affecting the noise is e , the feedback resistor (Rf ), and junction capacitor in the photodiode (C). Besides that, the design concept of multi channel TIA (8 channel) using IC Op Amp, with consideration of pin number of each Op Amp, supply needs, the initial value of Rf, converter to 8-DIP and feedback capacitor (Cfj) channel, also discussed
in this paper.

— While the selection of new "backbone" device structure in the era of post-planar CMOS is open to a few candidates, FinFET and its variants show great potential in scalability and manufacturability for nanoscale CMOS. In future, as the size of channel length decrease, the necessity of low power based circuit will be increased. In nanometer regime, CMOS based circuits may not be used due to problem in its fundamental material, short channel effect (SCE) and high leakage. To achieve low power device in nanometer region, it can be obtained by utilizing alternative devices like FinFET. This paper analyses an 8T two-stage op amp realized with FinFETs. Its most important design metric that is gain and its variability are analyzed at 32-nm technology node and compared with its CMOS counterpart. This study shows that there is a considerable improvement in feature like gain and its variability due to reduced SCE of FinFET. The FinFET-based op amp emerges out to be better between the two versions of op amp. Findings of our investigation infer that FinFET technology promises to restore the silicon industry by rescuing it from the SCEs that limit device scalability faced by current bulk-CMOS technology.

In this paper dynamic biasing technique is used for the enhancing the slew rate of the designed Op-Amp. The proposed FinFET based Op-Amp has been verified through Hspice simulator in the standard 45nm Silicon on Insulator FinFET library. The proposed op amp has two stages Miller compensated configuration. A biasing circuit (DSB circuit) is used for dynamic switching of the biasing voltage of the op amp. This leads to lower power consumption, wide ICMR range, and high gain stability. The proposed op amp has a power consumption of 661.83 μW. It has a dual supply voltage of-1.0V and 1.0V. The input common mode range (ICMR) is-800 mV to +900 mV. The Op-Amp has a slew rate of 1.5 KV/μs. Voltage gain of the op amp is 90.4dB. Due to the use of SOI FINFET devices the op amp has relatively less leakage current as compared to similar bulk MOSFET device op amps. The op amp has unity gain bandwidth of 1.27 GHz. Thus, it can be used to transmission and processing of audio and video signals.

Carbon Nano Tubes (CNTs) with their unique electronic and geometric features have emerged as candidates in next generation high-performance nano-electronics application. CNTs have played a significant role in overcoming the challenges of scaling process of traditional silicon/conventional MOS based devices and therefore, carbon nanotube field effect transistor (CNTFET) based circuit development has been boosted in recent years. The present review encompasses inquisitive assessment of CNTs and its application in designing of CNTFET based circuits in nano-electronics. Recently reported CNTFET based nanoelectronic circuits like three stage operational amplifiers (OP AMP), novel operational trans-conductance amplifier (OTA), universal logic circuits, tristate buffer, Cascode Operational Transconductance Amplifiers (COTA), folded cascode operational transconductance amplifiers (FC-OTAs), Ternary Full Adder Cell and pure CNT based multistage operational amplifier, as well as improvement in their performance parameters (DC gain, output resistance, slew rate, average power, speed and power consumption) as compared to respective MOS based circuits have been extensively reviewed. In order to harness the high quality intrinsic features of CNTs further investigations of nanotube-based-electronics are anticipated and considered as future perspective beyond silicon-based-electronics.

Bond graph is an integrated method of modeling which would be suitable for modeling mechatronic systems that are usually formed from electrical, mechanical and hydraulic systems. This paper presents a new bond graph model for one the important components of mechatronic systems: op amp. This model allows considering finite gain and non-zero input impedance op amps. To develop this method, open loop gain equation, information signals, and bicausality concept are applied. To represent the validity of the method, some examples are investigated and the state space equations are obtained.

Inverter is an obvious device to utilize the renewable energy resources. Pulse width modulation (PWM) technique is the most used technique for inverters. This paper represents the Sinusoidal PWM technique and shows how to generate PWM signal using different simple Op-Amp circuits for three phase voltage source inverter (VSI). It is a new design of Op-Amp circuit for switching the three phase PWM inverter. All the Op-Amp circuits have been simulated and their outputs have been shown step by step. This analog circuit (Op-Amp) controlled VSI has been simulated for both standalone load & high voltage sensitive loads/systems like micro-grid system and industrial machines respectively without and with transformer. The simulation results have been shown before and after harmonic reduction using a passive filter.

This paper presents the design of a first order and second order single bit Sigma-Delta Analog-to-Digital Converter (ADC) which is realized using CMOS technology. In this paper, a first Order and Second order Sigma-Delta ADC is designed which accepts an input signal of frequency 1 KHz, an OSR of128, and 256 KHz sampling frequency.It is implemented in a standard 90nm CMOS technology. The ADC operates at 0.5V reference voltage. The Design and Simulation of the Modulator is done using H-spice. This paper firstly elaborates Summer, Integrator, Comparator, D-Latch and DACwhich is integrated together to form Sigma Delta Modulator. Op-amp which is a key componentused in the design, has the open loop voltage gain of 80.5db, Phase Margin of 66 Degree, output resistance of 122.5KΩ, and power dissipation of 0.806 mW. Finally, a first order and second order single bit Sigma Delta ADC is implemented using ±2.5 power supply and simulation results are plotted using H-Spice.After the modulator is d...