[...]... improved Now such op-amps are 1 Appearance of operational amplifiers is associated with Harold S Black, who, working in Bell Labs, proposed op-amps for telephony in 1934 [2] Y.K Rybin, Electronic Devices for Analog Signal Processing, Springer Series in Advanced Microelectronics 33, DOI 10.1007/978-94-007-2205-7 1, © Springer ScienceCBusiness Media B.V 2012 1 2 1 Modern Operational Amplifiers called integral... are now used in the systems for data acquisition and signal processing of measurement information, entering of the analog signals into the computer, in audio and medical systems, etc [4–7] They are characterized by small size, wide range of power supply voltages, low consumed power, and others Besides, they are suitable for any operating conditions However, the main reason for wide application of op-amps... of the input signal increases, and the gain varies widely: from several tens or even hundreds thousands to 1 and even smaller In addition, in many circuits the op-amp is to operate with a large feedback, and the gain-frequency and the phase-response (PRC) characteristics should have a certain form, providing for some marginal stability Therefore, the op-amp GFC is corrected For example, for correction... stage The gain at a small signal in this case is K D k2 Vm ='T When amplifying pulsed signals and operating in the switching mode, the transient response characteristic (TC) is important Remind that TC is the time dependence of the output voltage at a stepwise change of the input voltage TC for small and large input signals are usually distinguished Small signals are the signals, at which the output... and this does not hinder them to create excellent computers Op-amps are considered as such circuit elements, for example, resistor or capacitor, with only somewhat more complex internal structure Moreover, the wide usage of software for modeling electronic devices on personal computers (Multisim, Electronics Workbench, DesignLab, Orcad, Protel, and others) approves this approach, because op-amps in such... these amplifiers are still referred to as operational and widely used in various electronic devices This term no longer carries the meaning that had at the beginning The word “operational” assumes some operation on signal, but an operational amplifier itself performs no other operations without external elements, but only signal amplification, which is its main and, perhaps, sole function Modern op-amps... 202 207 210 7 Signal Conditioners 7.1 Introduction 7.2 Resistive Sensor Signal Conditioners 7.3 Inductive Sensor Signal Conditioner 7.4 Optical Sensor Signal Conditioners 7.5 Thermocouple Signal Conditioners... the signals, variation of whose amplitude does not result in a change of the amplifier parameters Large signals are the signals, at which the output voltage can 8 1 Modern Operational Amplifiers Fig 1.7 Typical transient response characteristics of A741 amplifier at small (1) and large (2) signals take limit values In this case, transistors operate in the cutoff or saturation ranges, that is, high signals... load for the signal source and consumes the corresponding power from it The higher the input resistance, the lower the input current Iin , so the greater voltage part of the signal source comes to the op-amp input, and the lower is the power needed from the signal source Most of modern op-amps are characterized by high input resistance (1–10 M ) Due to this fact, the necessary current from the signal. .. Analysis of the Effect of Signal Source and Load 13 1.5 Analysis of the Effect of Signal Source and Load The signal source and the load influence a significant effect on the amplifier properties as a whole From the circuit of op-amp connection on Fig 1.12 , it can be seen that the resistors Zs, Zin, Zout, and Zload form voltage dividers In this case, the overall gain with regard for all resistances is Ke . proposed op-amps for telephony in 1934 [2]. Y.K. Rybin, Electronic Devices for Analog Signal Processing, Springer Series in Advanced Microelectronics 33,. devices for exciting sensors of physical parameters, in meters of frequency characteristics of amplifiers and filters, in devices for transformation of signal