Name: how a voltage doubler raises ac output
Uploaded: 2025-05-22T09:06:19.000Z
Duration: 1 min 23 s
Channel: JoVE

Considere um circuito duplicador de tensão composto por duas seções consecutivas: uma seção de fixação e uma seção retificadora.
A seção de fixação compreende um capacitor C1 e um diodo D1, enquanto a seção retificadora consiste em um diodo D2 e um capacitor C2.
Quando uma entrada senoidal de amplitude específica é aplicada à seção de fixação, ela gera uma forma de onda de tensão de saída através do diodo, assumindo o comportamento ideal do diodo.
Ele prende os picos positivos a zero volts, permitindo que o pico negativo atinja um valor duas vezes a amplitude da entrada senoidal.
A forma de onda de saída na seção de fixação serve como uma entrada para a seção retificadora.
Ele gera uma tensão CC através do capacitor C2, que equivale a duas vezes a amplitude da entrada senoidal.
Como a tensão de saída é o dobro do valor de pico da tensão de entrada, este circuito é conhecido como duplicador de tensão.
Esta técnica pode ser estendida para gerar tensões de saída com múltiplos mais altos da amplitude do sinusóide de entrada.
Os duplicadores de tensão são usados em várias aplicações, incluindo equipamentos científicos, processamento de sinal e conversores DC para DC em dispositivos eletrônicos.

circuito duplicador de tensão

Voltage Doubler Circuit

Um circuito duplicador de tensão integra dois componentes principais: uma seção de fixação e uma seção retificadora. A seção de fixação consiste em um capacitor (C_1) e um diodo (D_1), enquanto a seção retificadora é equipada com outro diodo (D_2) e um capacitor (C_2). Este circuito produz uma tensão de saída com o dobro da amplitude da tensão de entrada senoidal.

<img alt="Figure 1" src="/files/ftp_upload/15724/15724_Figure_1v2.svg" style="height: 132px;">

O circuito começa a operar quando uma entrada senoidal é introduzida na seção de fixação. Sob condições ideais, esta seção emite uma forma de onda de tensão através do diodo D_1, fixando efetivamente os picos positivos em zero volts e permitindo que o pico negativo atinja uma magnitude que é o dobro da amplitude da entrada senoidal. Esta forma de onda transformada da seção de fixação é então alimentada na seção retificadora. Aqui ocorre uma transformação notável, produzindo uma tensão CC no capacitor C_2. Esta tensão reflete duas vezes a amplitude da entrada senoidal inicial, proporcionando o efeito de duplicação que dá nome ao circuito e marca sua função primária.

O princípio por trás do duplicador de tensão não se limita apenas à duplicação, mas também pode ser adaptado para multiplicar a tensão de entrada por fatores mais elevados, ampliando seu escopo de aplicação. Os duplicadores de tensão são essenciais em vários campos, sendo utilizados em instrumentos científicos, aprimorando técnicas de processamento de sinais e servindo como componentes essenciais em conversores DC-DC em vários dispositivos eletrônicos. Essa capacidade de dobrar a tensão com eficiência torna o circuito duplicador de tensão uma pedra angular no projeto e aplicação eletrônica.

Circuito Duplicador de Tensão

Considere um circuito duplicador de tensão composto por duas seções consecutivas: uma seção de fixação e uma seção retificadora.
A seção de fixação compreende um ...

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how a voltage doubler raises ac output

A voltage doubler circuit raises the output voltage by using a clamping section and a rectifier section. The clamping section includes a capacitor, C1, and a diode, D1. The rectifier section includes a second diode, D2, and a capacitor, C2.

The circuit starts working when a sinusoidal input signal enters the clamping section. Under ideal conditions, this stage clamps the positive peaks at zero volts. It also lets the negative peak reach a magnitude that is twice the input amplitude.

That shaped waveform then moves into the rectifier section. There, the circuit produces a DC voltage across capacitor C2. This output equals twice the amplitude of the original sinusoidal input, which gives the circuit its voltage-doubling effect.

The same principle can also be extended to multiply the input voltage by higher factors. Because of this, voltage doublers are useful in scientific instruments, signal processing, and DC-DC converters found in many electronic devices. This makes the circuit an important part of electronic design and application.

How a Voltage Doubler Raises AC Output

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A voltage doubler circuit raises the output voltage by using a clamping section and a rectifier section. The clamping section includes a capacitor, C1, and a diode, D1. The rectifier section includes a second diode, D2, and a capacitor, C2. The circuit starts working when a sinusoidal input signal enters the clamping section. Under ideal conditions, this stage clamps the positive peaks at zero volts. It also lets the negative peak reach a magnitude that is twice the input amplitude. That...

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key terms and concepts

Learn how a clamping section and rectifier section work together in a voltage doubler circuit to produce a DC output with twice the input amplitude.

How a Voltage Doubler Raises AC Output | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

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How a Voltage Doubler Raises AC Output

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