Name: analyzing an op amp audio filter
Uploaded: 2024-04-11T12:48:50.000Z
Duration: 1 min 18 s
Channel: JoVE

Bir ses sisteminde, filtre devresi, bir amplifikatörden gelen yükseltilmiş ses sinyalini işler ve düşük frekanslı sinyal bileşenlerini güçlü bir şekilde zayıflatır.
R1 ve R2 dirençleri ve C1 kondansatörü ile birleştirilmiş ters çevirici bir konfigürasyonda bir op-amp'ten oluşan en basit filtre devresini düşünün. Bilinen bir giriş sinyali için ortaya çıkan çıkış sinyali nedir?
Kondansatörün empedansı, giriş voltajı için zaman alanı ifadesinden türetilen açısal frekans kullanılarak hesaplanır.
Frekans alanı eşdeğer devresi, polar formdaki giriş sinyalini ve Z1 ve Z2 empedanslarını temsil eder. Empedans Z2, C1 kondansatörü ve direnç R2'nin paralel kombinasyonuna karşılık gelir.
Kirchoff'un mevcut yasasını ve Ohm yasasını düğümde uygulamak, ideal bir op-amp için bir düğüm denklemi verir. Bu denklem yeniden düzenlendiğinde, çıkışın giriş voltajına oranının empedansların negatif oranına eşit olduğunu gösterir.
Bilinen ve hesaplanan değerler bu denkleme ikame edilerek, çıkış voltajı polar formda belirlenir ve daha sonra zaman alanına dönüştürülür.

op amp ac devreleri

Bir ses sisteminde filtre devresi, amplifikatörden gelen güçlendirilmiş ses sinyalinin işlenmesinde çok önemli bir rol oynar. Birincil işlevi, düşük frekanslı sinyal bileşenlerini önemli ölçüde zayıflatarak ses çıkışını şekillendirmektir. Bu devrenin işlemleri, temel filtre konfigürasyonuna odaklanılarak incelenmiştir. Bu konfigürasyon, dirençler (R1 ve r2) ve bir kapasitör (c1) ile birleştirilmiş, ters çevirici bir düzende düzenlenmiş bir işlemsel yükselteç içerir.

<img alt="Figure1" src="/files/ftp_upload/15116/15116_PT_Figure_1.svg" style="text-align: center; height: 164px;" />

Bilinen bir giriş sinyaliyle karşılaşıldığında zorluk, ortaya çıkan çıkış sinyalinin belirlenmesinde yatmaktadır. İlk adım, giriş geriliminin zaman alanı ifadesinden türetilen açısal frekans kullanılarak elde edilen kapasitörün empedansının hesaplanmasını içerir.

<img alt="Equation1" src="/files/ftp_upload/15116/15116_PT_Equation_1.svg" style="text-align: center; height: 36px;" />

Sonuç olarak analiz, giriş sinyalinin z1 ve z2 empedans bileşenlerinin yanında kutupsal formda temsil edildiği frekans alanına geçer. z2 açıkça kapasitör c1 ve direnç r2'nin paralel kombinasyonu ile ilgilidir. Analizin özü, Kirchhoff'un mevcut yasasını ve Ohm yasasını devredeki belirli bir düğüme uygulamaya ve böylece ideal bir op-amp için bir düğüm denklemi formüle etmeye dayanır. Bu denklem yeniden düzenlendiğinde kritik bir anlayışı ortaya çıkarır: Çıkışın giriş gerilimine oranı, empedansların oranıyla ters orantılıdır.

<img alt="Equation2" src="/files/ftp_upload/15116/15116_PT_Equation_2.svg" style="text-align: center; height: 36px;" />

Bilinen ve hesaplanan değerler, çıkış gerilimini kutupsal biçimde ortaya çıkarmak için bu denklemin içine ustaca yerleştirilir. Çıkış gerilimini temsil eden sonuç daha sonra zaman alanına dönüştürülebilir ve böylece filtre devresinin giriş sinyaline tepkisinin kapsamlı bir şekilde anlaşılması sağlanır. Analiz için, giriş terminallerinden hiçbirine akım girmemesi ve giriş terminallerindeki gerilimin sıfır kalması ilkesi de dahil olmak üzere, ideal op-amp özellikleri sıklıkla varsayılır.

Op Amp AC Devreleri

Bir ses sisteminde, filtre devresi, bir amplifikatörden gelen yükseltilmiş ses sinyalini işler ve sinyal bileşenlerini düşük ...

Education

JoVE Core

Electrical Engineering

Elektrik Mühendisliği

Unit 1

Ünite 1

AC Circuit Analysis

AC Devre Analizi

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

Op Amp AC Circuits

analyzing an op amp audio filter

An op amp audio filter shapes an amplified sound signal by strongly reducing the lower-frequency parts. In this circuit, the focus is on a basic filter setup used after an amplifier in an audio system. The filter uses an operational amplifier in an inverting arrangement with resistors R1 and R2 and a capacitor C1.

The analysis starts with a known input signal and asks for the output signal. To solve it, the capacitor impedance is found first. That requires the angular frequency from the time-domain form of the input voltage, so the work moves into the frequency domain.

In the frequency domain, the input signal is written in polar form. The impedances Z1 and Z2 are then used, with Z2 representing the parallel combination of capacitor C1 and resistor R2. At the same time, the ideal op amp assumptions are used. No current enters either input terminal, and the voltage across the input terminals is zero.

The final step is applying Kirchhoff's current law and Ohm's law at one node in the circuit. This creates a nodal equation for the ideal op amp. When that equation is rearranged, the output-to-input voltage ratio is shown to be inversely proportional to the impedance ratio. The known values are then substituted to find the output voltage in polar form, and that result can be converted back to the time domain for a full description of the filter response.

Analyzing an Op Amp Audio Filter

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An op amp audio filter shapes an amplified sound signal by strongly reducing the lower-frequency parts. In this circuit, the focus is on a basic filter setup used after an amplifier in an audio system. The filter uses an operational amplifier in an inverting arrangement with resistors R1 and R2 and a capacitor C1. The analysis starts with a known input signal and asks for the output signal. To solve it, the capacitor impedance is found first. That requires the angular frequency from the...

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Learn how an op amp audio filter reduces low-frequency signals. Follow impedance, nodal analysis, and polar-to-time-domain output calculations.

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JoVE Core Elektrik Mühendisliği, devre analizi teknikleriyle birlikte elektrik devrelerinin temel kavramlarını kapsayan, anlaşılması kolay animasyonlu videolar sunar. Operasyonel amplifikatörler ve devre dönüşümü kavramlarını kullanarak birinci dereceden ve ikinci dereceden devreleri içerir. Pratik tasarım örneklerinin ve gerçek dünya uygulamalarının bilim insanlarınca hazırlanan videolar aracılığıyla dahil edilmesi, karmaşık kavramları erişilebilir hale getirerek önemli bir eğitim değeri katmaktadır.

electrical engineering

Analyzing an Op Amp Audio Filter

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