OP AMP Applications
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The document presented an overview of operational amplifiers (OP-AMPs) given by Group 12. It defined an OP-AMP as an integrated circuit that amplifies input voltage through high gain. It described OP-AMP characteristics like high open-loop gain, large input resistance, and small output resistance. Common OP-AMP applications presented included comparators, integrators, differentiators, filters, and oscillators. Circuit diagrams were provided for low-pass filters, high-pass filters, and band-pass filters built using OP-AMPs.
![Differential and Common Gain
•
• Differential Gain (Ad):
• Ad = 1/2[R3/(R1+R3)] [(R4 + R2)/R2 + R4/R2]
• Mode Gain (Acm=VOUT/ Vcm)
• Acm = [R3/(R1+R3)] [(R4 + R2)/R2 - R4/R2]](https://image.slidesharecdn.com/ecdiipresentation-141101112024-conversion-gate01/85/OP-AMP-Applications-16-320.jpg)
OP AMP Applications
- 1. ECD II Presentation OP-AMP Applications
- 2. • Presented by Group 12 • Aroosa • Sheher • Sidra Ali
- 3. Introduction What is OP-AMP Mathematics of OP-AMP Characteristics of OP-AMP Ideal OP-AMP Types of OP-AMP Applications of OP-AMP Description of OP-AMP applications
- 4. What is Op Amp • An Operational Amplifier (Op-Amp) is an integrated circuit that uses external voltage to amplify the input through a very high gain What an Op-Amp looks like to a lay-person
- 5. What is an Op-Amp? – The Surface • What an Op-Amp looks • . like to an engineer
- 6. What is an Op-Amp? – The Inside • The actual count varies, but an Op-Amp contains several Transistors, Resistors, and a few Capacitors and Diodes. • For simplicity, an Op-Amp is often depicted as this: Inverting Input Non- Inverting Input Positive Power Supply Negative Power Supply Output
- 7. Mathematics of the Op-Amp • The gain of the Op-Amp itself is calculated as: G = Vout/(V+ – V-) • The maximum output is the power supply voltage • When used in a circuit, the gain of the circuit (as opposed to the op-amp component) is: Av = Vout/Vin
- 8. Op-Amp Characteristics • Open-loop gain G is typically over 9000 • But closed-loop gain is much smaller • Rin is very large (MΩ or larger) • Rout is small (75Ω or smaller)
- 10. Types of Op-Amps o Inverting oNon-inverting oSumming amplifier oThe voltage follower o Integrator oDifferentiator
- 11. Applications of Op-Amps • Comparator • Integration and differentiation • Charge amplifier • Capacitance multiplier • Oscillators • Filters • Audio and video preamplifiers and buffers
- 12. Applications of Op-Amps • Voltage regulator and current regulator • Digital-to-analog converter • Voltage clamps • Oscillators and waveform generators • Analog computer
- 13. Comparator . • Compares two voltages or currents and outputs a digital signal indicating which is larger. • Two analog input terminals and one Output • The op-amp's output voltage is limited by the supply voltage.
- 14. Integration •Performs the mathematical operation of Integration. • Output signal is determined by the length of time a voltage is present at its input as the current through the feedback loop charges or discharges the capacitor as the required negative feedback occurs through the capacitor.
- 15. Differentiation • Amplifies the difference between two voltages but does not amplify the particular voltages. =Common-mode gain of the amplifier. =Differential gain • Used to null out noise or bias-voltages that appear at both inputs, a low common-mode gain is usually desired.
- 16. Differential and Common Gain • • Differential Gain (Ad): • Ad = 1/2[R3/(R1+R3)] [(R4 + R2)/R2 + R4/R2] • Mode Gain (Acm=VOUT/ Vcm) • Acm = [R3/(R1+R3)] [(R4 + R2)/R2 - R4/R2]
- 17. Charge amplifier • Constructed using op-amps with a feedback capacitor. • The charge amplifier just transfers the input charge to another reference capacitor and produces an output voltage equal to the voltage across the reference capacitor • The circuit acts as a charge-to-voltage converter. • The input impedance of the circuit is almost zero
- 18. Capacitance Multiplier • Uses an amplifier to make a capacitor function like a capacitor that is much large. • Used as a capacitance multiplier in such a way that multiple small physical capacitances are combined in the integrated circuit technology to yield a large overall capacitance. • The aim is often to multiply the original capacitance value hundreds and thousands of times.
- 19. Oscillators • Produces a repetitive, oscillating electronic signal, often a sine wave or a square wave. • convert direct current (DC) from a power supply to an alternating current signal. • It contains an energy-storing element (a capacitor or, more rarely, an inductor)
- 20. Active FILTERS • Types: • Low pass filter • High pass filter • Band pass filter • Band reject filter
- 21. Active Filters • A filter contains a device like an Op Amp • LP allow low frequencies HP allow high frequencies • Cut of frequency :a cutoff frequency is a frequency level above or below where a device fails to operate. R2 + - + V0 __ + Vcc - Vcc - + R1 C Low pass filter Low pass filter transfer function Low pass filter Cutoff frequency
- 22. Low Pass Filter • Passes low frequency signals with amplification and gain control
- 23. Active Low Pass Filter with Amplification • the amplitude of the output is increased by the pass band gain, AF of the amplifier.
- 25. High Pass Filter • Passes high frequency signals with amplification and gain control First Order Active High Pass Filter with 1 Gain
- 26. Active Band Pass Filter • Frequency selective filter circuit • Range is set between two cut-off frequency points “lower frequency” ( ƒL ) and the “higher frequency” ( ƒH ) while attenuating any signals outside of these two points. • Made by cascading together a single Low Pass Filter with a single High Pass Filter .
- 27. Active Band Pass Filter Circuit
- 28. Band reject filter • Band stop filters reject a specified band of • frequencies and pass all others. • The response is opposite to that of a bandpass