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OPERATIONAL AMPLIFIERS

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The Operational amplifier is a linear integrated circuit that uses low supply voltages. It can be implemented in circuits to perform amplifications and math operations such as additions, subtractions, integrations and differentiation. Subjects covered are:

 

OPERATIONAL AMPLIFIERS:

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  • This chapter starts by introducing the operational amplifier (OP-Amp). It lays out the circuit block diagram of the op-amp and elaborates on the differential input stage and the output stage. The chapter also emphasizes the concept of negative feedback and how it affects op-amp circuit. The final stages of the chapter deals with the op-amp impedances and their importance when the op-amp circuit are coupled with other circuits. elements. The topics explained in this chapter are:

    • ​Introduction to Operational Amplifiers.

    • Op-Amps Stages of the Op-Amp.

      • The Differential Amplifier Stage.

      • The Level Shifter Stage.

      • The Push-Pull Output Stage.

    • Op-Amp Configurations With Negative Feedback.

    • Op-Amp Impedance and Noise.

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OP-AMP RESPONSES:

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  • This chapter deals with frequency related components such as frequency response, bandwidth, phase shift and the effect of negative feedback. Negative feedback and its effect on stability and its compensation circuits are examined. The topics explained in this chapter are:

    • ​Op-Amp Open-Loop Response.​

    • Op-Amp Closed-Loop Response.

    • Positive Feedback and Stability.

    • Op-Amp Compensation.

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BASIC OP_AMP CIRCUITS:

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  • Op-Amps are used in a vast majority of applications such as amplifiers, modulators, filters etc... The topics explained in this chapter are:

    • Nonlinear Op-Amp Circuits such as Comparators​.

    • Inverting Amplifiers.

    • Non-Inverting Amplifiers.

    • Integrators & Differentiators.

    • Converters and Other Op-Amp Circuits.

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MULTI-STAGE AMPLIFIERS:

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  • To increase the voltage gain of an amplifiers while maintaining stability, several; amplifier stages are used. There are various ways in which amplifiers are cascaded and coupled together. The topics covered in this chapter are:

    • Cascading Amplifiers.​

    • Direct Coupled Multistage Amplifiers.

    • RC Coupled Multistage Amplifiers.

    • Impedance Matching.

    • Transformer Coupled Multistage Amplifiers.

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OP-AMP ACTIVE FILTERS:

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  • Active filters are circuits that allow signals to pass from the input to the output based on their frequencies. while attenuating others that have other frequencies. That action is termed as selectivity. Active circuits use devices that are active such as BJTs & FETs along with passive elements which are the Resistor, Capacitor and Inductor. The circuit construction provides voltage gain and the networks that provide selectivity such as RL, RC, LC,  and LRC networks. The topics explained in this chapter are:

    • Basic Filters & their Frequency Responses.

    • Active Low Pass Filters.

    • Active High Pass Filters.

    • Active Band Pass Filters.

    • Active Band Stop Filters or Reject Filters.

    • Cascaded Filters.

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NONLINEAR CIRCUITS, OSCILLATORS AND TIMERS:

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  • Ever wondered about how a broadcast so far away get to your house hold? The answer is all data generated by the broadcast ride an electromagnetic waveform called a carrier. This waveform is the output of a circuit called the Oscillator circuit. The oscillator circuit is nearly found in almost all electronics. For a circuit to oscillate it requires both positive feedback and negative feedback.  Oscillators provide various types of waveforms such as Sine waveforms, Rectangular waveforms, Triangular waveforms and Sawtooth waveforms. Timers are generally oscillators, the most popular oscillator is the 555 Timer. The topics covered in this chapter are:

    • The Oscillator Circuit.

    • Positive & Negative Feedback.

    • The Barkhausen Criteria.

    • RC Oscillators.

    • LC Oscillators.

    • Relaxation Oscillators.

    • The 555 Timer MonoStable Mode.

    • The 555 Timer Astable Mode.

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VOLTAGE REGULATORS:

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  • If you have been in an electronic lab conducting experiments, most likely you have used a DC power supply. The output of the power supply is actually the output of a voltage regulator that keeps the DC voltage constant regardless of the load or input voltage variations. Regulators provide both positive and negative voltages. The topics covered in this chapter are:

    • Voltage Regulation.​

    • Series Regulators.

    • Shunt Regulators.

    • Switching Regulators.

      • Step Down Regulators. Buck Converters.​

      • Step Up Regulators, Boost Converters.

    • Integrated Circuit Voltage Regulators.​

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