A Microcontroller based digital pH meter was designed and developed to measure the value of pH (acidity or alkalinity) for any type of solution. Two op-amps of high input impedance and low output impedance were used to design the pH meter: one is used as a buffer and the other as a summing amplifier. The output of the summing amplifier is connected to the microcontroller as an input. The pH val...

Operational amplifiers (op amps) are as prolific in analog circuits as salt and pepper is on food. They are sprinkled throughout the sensor data acquisition system, performing a variety of functions. For instance, at the sensor interface, amplifiers are used to buffer and gain the sensor output. The current or voltage excitation to the sensor, quite often is generated by an amplifier circuit. F...

A method is presented in this paper for the design of a high frequency CMOS operational amplifier (OpAmp) which operates at 3V power supply using tsmc 0.18 micron CMOS technology. The OPAMP designed is a two-stage CMOS OPAMP followed by an output buffer. This Operational Transconductance Amplifier (OTA) employs a Miller capacitor and is compensated with a current buffer compensation technique. ...

DStat relies on three op-amps: the control and buffer amplifiers in the potentiostat (U1 and U2 in Fig. 2(c) in the main text) and the transimpedance amplifier in the current measurement circuit (U3 in Fig. 3(b) in the main text). In DStat, these amplifiers are the LMP7702 (Texas Instruments, Dallas TX, USA) for control and buffer and LMP7721 (Texas Instruments) for transimpedance, respectively...

In this paper, a low power and high CMRR Instrumentation Amplifier is presented. It has been designed for use in Bio-Impedance (BI) applications that operate within the beta dispersion frequency range. An IA with a high CMRR and input impedance allows the extraction of the low amplitude BI signal while reducing the error signals and noise associated with the tissue and instrument interface. The...

A novel technique for a self-equalized distributed amplifier is presented by showing the analogy between transversal filters and distributed amplifier topologies. The appropriate delay and gain coefficients of amplifier circuit are obtained by a Fourier expansion of the raised cosine spectrum in the frequency range of 0-40GHz.

In this paper, we propose the idea of using transimpedance amplifiers, in lieu operational amplifiers (OAs) or transconductance (OTAs) to design capacitively coupled AC amplifiers. The is demonstrated with a current feedback amplifier (CFOA) as an active element, which actually architecture consisting voltage buffers and copiers (mirrors). This last characteristic further exploited make corner ...

In this paper a new method for the design of a linear phase distributed amplifier in 180nm CMOS technology is presented. The method is based on analogy between transversal filters and distributed amplifiers topologies. In the proposed method the linearity of the phase at frequency range of 0-50 GHz is obtained by using proper weighting factors for each gain stage in cascaded amplifier topology....

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 openloop 3 dB point at infin...