Op-Amp (Operational Amplifier)

Prof MAD
18 Aug 202317:14

Summary

TLDREl script proporciona una introducción a los amplificadores operacionales (op-amps), componentes fundamentales en circuitos analógicos. Se explica que un op-amp es un amplificador de voltaje altamente configurable capaz de realizar operaciones matemáticas. Se discuten sus características, como su alto ganancia y la falta de corriente en sus entradas, siguiendo las 'reglas doradas' del diseño de circuitos. Se presentan aplicaciones básicas como comparadores de voltaje, buffers de voltaje, amplificadores no inversores e inversores, demostrando cómo el op-amp amplifica y/o invierte señales eléctricas. El video concluye prometiendo futuras discusiones sobre aplicaciones prácticas más avanzadas.

Takeaways

  • 🔍 Un amplificador operacional (op-amp) es un componente básico en los circuitos analógicos que amplifica la señal eléctrica y realiza operaciones matemáticas.
  • 🎚️ Los op-amps tienen dos entradas, una inversora y otra no inversora, y una salida, y su diseño permite realizar comparaciones y cálculos con señales de voltaje.
  • 🔌 El suministro de energía de un op-amp suele ser de 5 a 15 volts tanto positivo como negativo, lo que permite que la salida oscile entre ambos niveles.
  • 📊 La ganancia de un op-amp es una medida de cuánto más grande es la salida en comparación con la diferencia de voltaje de entrada.
  • 🔄 El op-amp puede trabajar en configuraciones de bucle abierto y bucle cerrado, siendo el bucle cerrado esencial para limitar la ganancia y realizar amplificaciones y operaciones matemáticas.
  • 👉 Las reglas doradas del diseño de circuitos con op-amps incluyen que la ganancia de bucle abierto es infinita, no hay corriente en las entradas y la salida ajusta para eliminar diferencias de voltaje en las entradas.
  • 🔌 El op-amp como comparador de voltaje se satura cuando la salida alcanza los límites del suministro de energía.
  • 🔗 La retroalimentación es crucial en los op-amps para controlar la ganancia y evitar la saturación, permitiendo realizar amplificaciones y operaciones matemáticas de manera efectiva.
  • 🔄 El op-amp como buffer de voltaje permite mantener la relación de divisor de voltaje sin que la carga afecte la señal de entrada.
  • 📈 El amplificador no inversor es una aplicación del op-amp que amplifica y mantiene la misma fase de la señal de entrada, ajustando la ganancia con resistencias externas.
  • 📉 El amplificador inversor es una aplicación del op-amp que amplifica y invierte la señal de entrada, también utilizando resistencias para ajustar la ganancia.

Q & A

  • ¿Qué es un operacional amplificador (op-amp) y qué hace?

    -Un operacional amplificador, o op-amp, es un circuito electrónico diseñado para amplificar la señal de voltaje. Su función principal es aumentar la magnitud de una señal eléctrica débil, tomando una señal de entrada y haciendo que sea más poderosa en la salida.

  • ¿Por qué se necesita un amplificador para señales eléctricas?

    -Se necesitan amplificadores porque muchas señales eléctricas son débiles y necesitan ser reforzadas antes de poder ser procesadas, transmitidas o usadas para impulsar dispositivos de salida, como en el caso de un sistema de audio con un micrófono y un altavoz.

  • ¿Cómo surgieron los op-amps en el contexto de las computadoras analógicas?

    -Los op-amps surgieron para realizar cálculos matemáticos con voltajes y corrientes en computadoras analógicas. Permitían realizar operaciones matemáticas complejas con señales de voltaje, como sumar, restar, dividir, multiplicar, calcular derivadas e integrales, con ajustes mínimos.

  • ¿Cuál es la función de los sensores de temperatura en un ejemplo de computadora analógica?

    -Los sensores de temperatura en un ejemplo de computadora analógica se utilizan para medir y proporcionar la temperatura de diferentes contenedores, donde la salida de voltaje de cada sensor está proporcional a la temperatura del contenedor.

  • ¿Cómo se representa un op-amp en un diagrama de circuito?

    -Un op-amp se representa en un diagrama de circuito por una forma de triángulo simple, donde los componentes internos no se representan individualmente.

  • ¿Cuáles son las dos entradas de un op-amp y qué significan?

    -Un op-amp tiene dos entradas: una llamada entrada inversora (con una marca de signo negativo o menos) y otra llamada entrada no inversora (con una marca de signo positivo o más).

  • ¿Qué son las reglas doradas del diseño de circuitos con op-amps y cuáles son?

    -Las reglas doradas son pautas para diseñar circuitos con op-amps basadas en sus características. La primera regla dice que la ganancia de banda abierta de un op-amp es infinita en teoría. La segunda regla indica que no hay corriente entrando o saliendo de las entradas del op-amp. La tercera regla establece que con retroalimentación negativa, la salida del op-amp cambiará para hacer que la diferencia de voltaje entre sus entradas sea cero.

  • ¿Qué es un amplificador no inversor y cómo se configura?

    -Un amplificador no inversor es una aplicación básica del op-amp donde la entrada se conecta a la entrada no inversora y la salida se conecta a la entrada inversora a través de un resistor. La ganancia de este amplificador se ajusta mediante los valores de los resistores R1 y R2.

  • ¿Cómo funciona un amplificador inversor y cuál es su ganancia?

    -Un amplificador inversor toma la entrada en la entrada inversora a través de un resistor R1 y tiene un camino de retroalimentación desde la salida al inversor a través de un resistor R2. La ganancia de este amplificador es -R2 dividido por R1, lo que indica que la señal de entrada se invertirá y se amplificará según la ganancia establecida.

  • ¿Qué es un comparador de voltaje y cómo funciona?

    -Un comparador de voltaje es una configuración del op-amp que se usa para comparar dos voltajes y dar una salida según la diferencia entre ellos. Si la diferencia de entrada es cero, la salida también es cero. Si la entrada no inversora tiene un voltaje ligeramente más alto, la salida se satuarará en el voltaje de alimentación positivo. Si es más baja, se satuarará en el voltaje de alimentación negativo.

  • ¿Qué es un buffer de voltaje y cómo ayuda a evitar la distorsión en un divisor de voltaje?

    -Un buffer de voltaje es una configuración del op-amp donde la salida se conecta directamente a la entrada inversora. Ayuda a evitar la distorsión en un divisor de voltaje al proporcionar la corriente del suministro de energía conectado al op-amp, eliminando así la alteración de los valores del divisor de voltaje debido a la carga.

Outlines

00:00

🔌 Introducción a los Amplificadores Operacionales (Op-Amp)

El Op-Amp, o amplificador operacional, es una pieza clave en la construcción de circuitos analógicos electrónicos, junto con resistencias, capacitores, diodos y transistores. Su función principal es aumentar la magnitud de una señal eléctrica, tomando una señal de entrada débil y produciendo una señal de salida más potente. Este proceso es esencial para sistemas electrónicos que requieren señales fuertes para procesar, transmitir o activar dispositivos de salida, como en el caso de un sistema de audio que utiliza un micrófono y un altavoz. Además, los Op-Amps tienen la capacidad de realizar operaciones matemáticas variadas con ajustes mínimos, lo que los hace versátiles para tareas como la diferenciación, integración y otros cálculos con voltajes. Se fabrican comúnmente como circuitos integrados (ICs) para facilitar su uso en diseños de circuitos.

05:02

🔌 Características y Configuraciones del Op-Amp

Los Op-Amps cuentan con entradas de inverting y non-inverting, y tienen una amplia ganancia, que es la relación entre la diferencia de voltaje de entrada y la voltaje de salida. Esta ganancia es un parámetro crítico que define el factor de amplificación del Op-Amp. Aunque no se pueden utilizar como amplificadores diferenciales por sí solos debido a su alta ganancia interna, pueden funcionar como comparadores de voltaje cuando se conectan a una fuente de alimentación. La salida del Op-Amp puede 'saturar', alcanzando los límites de la fuente de alimentación, tanto positiva como negativa. Además, se pueden configurar en circuitos abiertos para crear comparadores o en circuitos cerrados con retroalimentación para realizar amplificación y operaciones matemáticas.

10:04

🔌 Reglas de Oro y Aplicaciones Básicas del Op-Amp

Las reglas de oro para el diseño de circuitos con Op-Amp son importantes para comprender su funcionamiento. La primera regla establece que la ganancia de banda abierta es teóricamente infinita, aunque en la práctica es de alrededor de 200,000. La segunda regla afirma que no hay corriente que entre o salga de las entradas del Op-Amp, lo que implica una impedancia de entrada infinita. La tercera regla dice que con retroalimentación negativa, la salida del Op-Amp cambiará para eliminar cualquier diferencia de voltaje entre sus entradas. Aplicaciones básicas del Op-Amp incluyen el comparador de voltaje, el buffer de voltaje y el amplificador no inverso, donde se utiliza la retroalimentación para controlar y limitar la ganancia, y se pueden ajustar los valores de los resistores para configurar la ganancia deseada.

15:07

🔌 Amplificadores Invertidos y Otras Aplicaciones del Op-Amp

El amplificador inverso es una variación del amplificador no inverso, donde la entrada se toma en la entrada inverting y hay una retroalimentación desde la salida a través de un resistor. Este diseño no solo amplifica la señal de entrada sino que también la invierte, con una ganancia dada por -R2/R1. La negatividad de la ganancia indica la inversión de la señal. Además de los amplificadores inverso y no inverso, los Op-Amps pueden utilizarse en aplicaciones como amplificadores de suma de voltaje, amplificadores integradores y diferenciales. Se espera que en futuras entregas se profundice en estas y otras aplicaciones prácticas de los Op-Amps.

Mindmap

Keywords

💡Amplificador

Un amplificador es un circuito electrónico diseñado para aumentar la amplitud o magnitud de una señal eléctrica. En el video, se destaca cómo los amplificadores son esenciales para fortalecer señales débiles antes de procesar, transmitir o utilizarlas para impulsar dispositivos de salida, como en el caso del sistema de audio donde la señal del micrófono debe ser amplificada para poder ser manejada por el altavoz.

💡Op-amp

El término 'op-amp' se refiere a un 'amplificador operacional', un componente fundamental en los circuitos analógicos. Se compone de la palabra 'operational', que sugiere que puede realizar operaciones matemáticas, y 'amplifier', que indica su función de amplificar señales. En el video, se describe cómo el op-amp no solo amplifica la diferencia de voltaje entre sus entradas sino que también puede usarse para realizar cálculos matemáticos.

💡Entrada no invirtiendo

La 'entrada no invirtiendo' es una de las dos entradas del op-amp, marcada con un signo positivo o más. Es importante en la configuración del circuito, ya que la diferencia de voltaje entre la entrada no invirtiendo y la entrada invirtiendo determina la señal de salida. En el video, se menciona que esta entrada juega un papel crucial en la amplificación y en la comparación de voltajes.

💡Entrada invirtiendo

La 'entrada invirtiendo' es la otra entrada del op-amp, marcada con un signo negativo o menos. Es donde se conecta la señal de referencia en muchos casos, y su diferencia con la entrada no invirtiendo es la que el op-amp amplifica. En el video, se utiliza esta entrada para ajustar la señal de referencia en un comparador de voltajes.

💡Ganancia

La 'ganancia' de un op-amp es la relación entre la amplitud de la señal de salida y la diferencia de voltaje entre las entradas. Es una medida de cuánto más grande será la señal de salida en comparación con la diferencia de voltaje de entrada. En el video, se explica cómo la ganancia es un parámetro crítico que determina el factor de amplificación del op-amp.

💡Saturación

La 'saturación' se refiere al estado en el que la salida del op-amp alcanza el nivel máximo o mínimo de su fuente de alimentación, lo que impide una mayor amplificación de la señal de entrada. Es un concepto clave en el video, donde se ilustra cómo el op-amp se comporta cuando la diferencia de voltaje entre las entradas es demasiado grande para ser amplificada dentro de los límites del suministro de energía.

💡Buffer de voltaje

Un 'buffer de voltaje' es una aplicación del op-amp que se utiliza para mantener constante el voltaje de entrada al proporcionar una salida que no se ve afectada por la carga. En el video, se describe cómo este tipo de buffer es útil para evitar la distorsión de los valores de un divisor de voltaje al conectar un carga.

💡Amplificador no invirtiendo

Un 'amplificador no invirtiendo' es una configuración del op-amp donde la señal de entrada se amplifica sin invertir su fase. En el video, se analiza cómo este tipo de amplificador utiliza resistores para determinar la ganancia y cómo la señal de salida se mantiene en la misma fase que la de entrada.

💡Amplificador invirtiendo

Un 'amplificador invirtiendo' es una configuración del op-amp donde la señal de entrada se amplifica y se invierte su fase. En el video, se explica cómo este tipo de amplificador utiliza un resistor de retroalimentación para invertir la señal y cómo la señal de salida tiene una fase opuesta a la de entrada.

💡Regla de oro del op-amp

Las 'reglas de oro del op-amp' son principios básicos que ayudan a los diseñadores de circuitos a entender y analizar el comportamiento de los op-amps. En el video, se mencionan tres reglas de oro: la ganancia de banda abierta es teóricamente infinita, no hay corriente entrante ni saliente en las entradas, y con retroalimentación negativa, la salida del op-amp cambiará para eliminar cualquier diferencia de voltaje entre las entradas.

Highlights

Op-amps are basic building blocks of analog electronic circuits, combining operational and amplification functions.

An amplifier increases the strength of an electrical signal, essential for processing, transmitting, or driving output devices.

Operational amplifiers were developed to perform various mathematical operations with minimal adjustments.

Op-amps can be built from discrete components or as integrated circuits, simplifying the design process.

Op-amps are symbolized by a simple triangle shape in circuit diagrams, representing their internal components.

An op-amp has two input terminals and one output terminal, with specific roles for each.

The gain of an op-amp is a critical parameter, representing how much larger the output voltage will be compared to the input voltage difference.

Op-amps can be used as voltage comparators, with the output saturating at the power supply voltage limit.

Adjusting the inverting input voltage allows for comparison with the input signal, creating a square wave output.

Op-amps have three golden rules that simplify their behavior prediction in different configurations.

The voltage buffer application of op-amps ensures the output voltage equals the input voltage without disturbing the source.

Non-inverting amplifiers use op-amps to amplify and maintain the phase of the input signal.

Inverting amplifiers invert and amplify the input signal, with gain determined by the feedback resistor.

The golden rules of op-amps include infinite open-loop gain, zero input current, and output adjustment to eliminate input voltage difference.

Upcoming episodes will cover more applications like voltage summing amplifiers, integrating amplifiers, and differentiating amplifiers.

Transcripts

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as well as resistors capacitors diodes

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and transistors op amps are one of the

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basic building blocks of analog

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electronic circuits

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so what is an op-amp OP comes from

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operational and amp comes from amplifier

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an amplifier is an electronic circuit

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that increases the strength or magnitude

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of an electrical signal

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it takes a weak input signal and makes

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it larger producing a more powerful

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output signal

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many electronic signals are weak and

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need to be strengthened before they can

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be processed transmitted or used to

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drive output devices

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consider an audio system with a

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microphone and a speaker

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the microphone converts voice into an

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electric signal and the speaker converts

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that signal back into voice the issue is

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that the microphone's output signal is

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weak and not strong enough to drive the

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speaker directly

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to make the signal strong enough we need

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to amplify it that's where the amplifier

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comes in

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the primary role of an amplifier is to

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increase the voltage of the input signal

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without significantly distorting its

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quality

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there are different types of amplifiers

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amplifiers are crucial in ensuring that

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weak signals become powerful enough to

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drive output devices effectively

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so what is special about operational

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amplifiers

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long before the Advent of digital

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electronic technology computers were

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built to electronically perform

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calculations by employing voltages and

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currents to represent numerical

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quantities for example imagine we have

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three water containers with different

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temperatures we need to get the average

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temperature of these three temperatures

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automatically in real time

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how can we make such a system we can

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place a temperature sensor in each

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container the output voltage of each

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sensor is proportional to the

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temperature of each room's temperature

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but how can we get the average of these

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three voltages

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for that we need to design a special

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circuit it should be able to give the

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average of these three inputs

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and then we can determine the average

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temperature using the output voltage

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this is an analog computer that computes

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the average of its input here is another

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example an analog computer that computes

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the difference between two sensor

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signals

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likewise many electronic systems require

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performing calculations involving

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voltages which include tasks like

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finding the voltage difference between

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two points adding or summing up voltage

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values dividing voltage by a constant

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Factor multiplying voltage by a constant

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Factor calculating the rate of change of

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voltage over time which is the

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derivative

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and determining the accumulated effect

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of voltage over a certain time period

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which is the integral

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to eliminate the need for Designing

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separate circuits for every specific

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calculation Engineers pursued a more

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adaptable approach they aim to find a

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component that could handle various

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mathematical operations with minimal

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adjustments this Pursuit resulted in the

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development of the operational amplifier

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intentionally crafted to serve as a

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flexible foundational unit for such

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calculations the word operational comes

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from the idea that these amplifiers were

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intended to operate or function in

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specific mathematical configurations the

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name operational amplifiers implies that

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this device can do mathematical

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operations and also has the ability to

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increase magnitude of an electrical

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signal

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so op amps are basically a voltage

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amplifying device which can be used to

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perform various mathematical operations

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op amps like any amplifier circuit can

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be built from discrete components that

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is resistors capacitors and transistors

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or even using valves but it is a

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laborious and complex task to simplify

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the process and make them more

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accessible to engineers and designers

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manufacturers produce op amps as

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integrated circuits or ICS

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instead of drawing complex circuit

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diagrams op amps are often symbolized by

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a simple triangle shape where the

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internal components are not individually

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represented since many applications of

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op-amps require two or more of them

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pairs or quartets of op amps are

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frequently packaged together

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they are very affordable you can buy

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dozens of op-amp ics for less than a

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dollar

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a single op amp has two input Terminals

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and one output terminal

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one of the inputs is called the

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inverting input marked with a negative

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or minus sign the other input is called

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the non-inverting input marked with a

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positive or plus sign

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the V plus and V negative power supply

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terminals are connected to the positive

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and negative terminals of a DC voltage

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source respectively these will often be

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in the range of positive 5 volts to 15

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Volts for the positive Supply and

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negative 5 volts to 15 Volts for the

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negative Supply this dual Supply

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Arrangement allows for the output

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voltage to swing both above and below

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zero volts

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the operational amplifier's output Port

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can both sync and Source either a

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voltage or a current

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when designing a circuit around an

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op-amp it is good to be familiar with

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its characteristics the primary defining

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feature of an op-amp is its gain

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as previously discussed op-amps have the

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special ability to amplify input

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voltages more precisely they amplify the

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voltage difference between their two

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input terminals

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the gain of an op amp represents how

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much larger the output voltage will be

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compared to the input voltage difference

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if the inverting input voltage is V1

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non-inverting input voltage is V2 and

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the output voltage is V3 then the gain

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will be V3 divided by V2 minus V1 this

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gain is a critical parameter that

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determines the amplification factor of

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the op amp

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even though the op amps amplify the

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difference between its inputs op amps

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cannot be used as a differential

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amplifier on their own because the

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internal gain of an op-amp is really

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high the typical real value is about 200

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000.

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for an example imagine the difference

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between the input terminals is just one

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millivolts

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since the gain is enormous the output

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voltage will be theoretically about 200

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volts making it unmanageable and

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impractical in most scenarios in

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practice the op amp can only amplify the

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voltage up to the level of its power

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supply

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however this characteristic can be

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effectively utilized in voltage

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comparators

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here we have an op amp that has a gain

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of 200 000 and connected to plus 10

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volts and negative 10 volts power supply

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let's set the inverting input at zero

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volts we are going to compare the

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voltage of non-inverting input with the

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voltage of inverting input which is 0

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volts and give output according to it

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the output voltage is equal to the gain

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times the input voltage difference

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if the voltage difference of inputs is

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zero the output is also zero

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if the voltage at the non-inverting

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input is slightly increased the op amp

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attempts to amplify this voltage

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difference in such cases the output

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theoretically needs to become

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substantially higher but there's a

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limitation the op amp can only amplify

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the voltage up to the level of its power

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supply which is 10 volts

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when the output reaches this maximum

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value it's referred to as saturation

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in essence the op amp becomes saturated

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when its output hits the supply voltage

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limit

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like Vice if the voltage of inverting

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input is slightly lower than the

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non-inverting

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the op amp attempts to amplify this

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small voltage difference into negative

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200 volts but since the power supply

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limit is negative 10 volts the output

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saturates at the negative Supply voltage

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the working summary of op amp voltage

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comparator can be shown like this if the

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voltage difference of inputs is zero the

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output will be zero if the voltage of

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non-inverting input is higher than the

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inverting input the op amp is saturated

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at positive Supply voltage if the

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voltage of non-inverting input is lower

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than the inverting input the op amp is

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saturated at negative Supply voltage

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instead of grounding the inverting input

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we can make its voltage adjustable like

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this so we can set any value in Supply

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voltage range then it compare the input

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voltage with that value

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for example let's set the inverting

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input to plus 5 volts if the input is a

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sine wave the output will be negative 10

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volts for the input values less than 5

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volts and the output will be positive 10

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volts for the input values more than

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positive 5 volts the resulting output is

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a square wave

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in this configuration the op amp

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Compares its input voltages and

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saturates the output terminal

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accordingly

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the uniqueness of op amp extends beyond

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their use as comparators

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while they can serve as comparators in

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specific scenarios their versatility

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goes far beyond this role

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to make op amps usable as differential

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amplifiers in real-world applications

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external components such as feedback

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resistors are essential to control and

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limit the overall gain feedback path

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connects the output to the input we call

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this closed loop configuration

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now we know two op amp configurations

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open loop configuration is used to

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create comparators the closed loop

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configuration is used to configure the

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op amp to do the amplification and

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mathematical operations before going

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further there are few things to explain

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to help circuit designers and

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enthusiasts rules have been developed in

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designing circuits using an op amp based

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on their characteristics such rules are

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commonly known as the golden rules

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as we discussed earlier the open loop

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gain is the gain of the op amp without

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positive or negative feedback ideally

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the open loop gain of an op amp will be

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infinite that's the first Golden Rule of

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op amp but practically this value is

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about 200 000 not Infinity

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the second rule states that no current

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enters or leaves the op amp inputs which

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means the input currents are effectively

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zero in simpler terms an ideal op amp

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has infinite input impedance which means

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it draws no current from the input

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sources connected to its inputs although

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ideally it is assumed that the input

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impedance of an op amp is infinite and

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has zero current flow into the inside

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real op amps have input leakage currents

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from a few Pico amps to a few milliamps

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the third rule states that in a circuit

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with negative feedback the output

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voltage of an op amp will change in

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whatever way is necessary to make the

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voltage difference between its two

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inputs zero in other words an ideal op

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amp will adjust its output voltage to

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eliminate any voltage difference between

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its inverting and non-inverting inputs

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these golden rules help in understanding

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and analyzing op amp circuits

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these rules are based on the ideal

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characteristics of op amps and provide

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simplified guidelines for predicting

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their behavior in different

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configurations

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keep those rules in mind let's discuss a

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few more applications and try to analyze

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those using golden rules the next most

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basic application of the op amps is the

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voltage buffer it's really simple we

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just have to connect the output directly

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to the inverting input what happens if

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we apply one volts to the non-inverting

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input

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look at the rule number three the op amp

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tries to change its output to make sure

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whatever is the voltage present in the

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non-inverting input is also present in

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the inverting input

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so the output voltage has also become

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one volts

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consequently in this configuration the

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output voltage becomes equal to the

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input voltage as the voltage output is

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equal to the voltage input students

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might become puzzled and wonder whether

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this kind of circuit has any practical

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application actually there are many

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think we have this kind of voltage

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divider and we need to power up some

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load if we directly connect the load

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like this since the current is flowing

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through the load the load will affect

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the voltage ratio of the resistance and

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change the voltage V1

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to avoid this we can use an op amp

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buffer to this point and power up our

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load according to rule number two no

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current flows in or out from the inputs

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so the op-amp will not disturb the

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voltages V1 and V2 the load's current is

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provided by the power supply connected

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to the op amp eliminating the Distortion

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of the voltage divider's values

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another important application of op-amps

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is non-inverting amplifier the

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configuration of non-inverting amplifier

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is like this let's first analyze the

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circuit if the VN is applied to the

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non-inverting input directly according

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to the Golden Rule 3 the voltage of the

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inverting input also has to be the same

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since the R1 is grounded from one side

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the voltage across it is v in and the

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voltage across the R2 is equal to V out

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minus V in

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according to the golden rule 2 no

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current flows to the op amp through the

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input

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so the current flowing through the R1

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and R2 is equal

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that current can be written as voltage

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across each resistor divided by the

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resistance like this now we can

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rearrange the equation and calculate the

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V out

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the gain of this non-inverting amplifier

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is R1 plus R2 divided by R1

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we can adjust the values of R1 and R2 to

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set the gain of this non-inverting

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amplifier as needed

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if the input is a sine wave then the

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output of the non-inverting input will

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be like this

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input is Amplified according to the gain

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and it's not inverted the word invert

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will be more clear to you in our next

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example

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our final example for this episode is

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the inverting amplifier it's very close

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to our previous example but there are

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few differences in an inverting

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amplifier the input is taken to the

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inverting input through a resistor R1 a

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feedback path is provided from the

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output via the resistor R2 to the

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inverting input look closely for ease of

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representation inverting and

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non-inverting inputs are swapped here

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let's analyze the circuit since the

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non-inverting input is connected to

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ground the voltage of non-inverting

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input is zero volts according to the

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Golden Rule 3 the voltage of the

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inverting input also has to be the same

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so the voltage of inverting input is

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also become 0 volts

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the voltage across R1 is 0 minus V in

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and the voltage across R2 is V out minus

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zero according to the golden rule 2 no

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current flows to the op amp through the

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input so the current flowing through the

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R1 and R2 is equal that current can be

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written as voltage across each resistor

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divided by the resistance now we can

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rearrange the equation and calculate the

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V out the gain of this inverting

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amplifier is minus R2 divided by R1 the

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negative sign is very important it

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indicates that the input is inverted so

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this amplifier not only amplify the

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input but also inverts it we can adjust

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the values of R1 and R2 to set the gain

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of this inverting amplifier as needed

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if the input is a sine wave then the

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output of the inverting amplifier will

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be like this

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input is Amplified according to the gain

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but it's inverted

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in this episode we've covered the

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fundamental applications of op-amps

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including the voltage comparator voltage

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buffer non-inverting amplifier and

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inverting amplifier in our upcoming

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episode we'll delve into more practical

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applications such as voltage summing

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amplifiers integrating amplifiers and

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differentiating amplifiers if you have

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any questions feel free to leave them in

play16:57

the comments below your feedback is

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greatly appreciated and motivates us

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thank you for watching and don't forget

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to like subscribe and stay tuned for

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more captivating educational videos

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Related Tags
Circuitos AnalógicosAmplificadoresOperacionalesElectrónicaAmplificaciónSistemas ElectrónicosMatemáticasConfiguracionesGolden RulesAplicaciones PrácticasEducativo
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