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

Considérons un circuit de doubleur de tension composé de deux sections consécutives : une section de serrage et une section redresseuse.
La section de serrage comprend un condensateur C1 et une diode D1, tandis que la section redresseuse se compose d’une diode D2 et d’un condensateur C2.
Lorsqu’une entrée sinusoïdale d’amplitude spécifique est appliquée à la section de serrage, elle génère une forme d’onde de tension de sortie à travers la diode, en supposant un comportement idéal de la diode.
Il fixe les pics positifs à zéro volt tout en permettant au pic négatif d’atteindre une valeur deux fois l’amplitude de l’entrée sinusoïdale.
La forme d’onde de sortie à travers la section de serrage sert d’entrée à la section redresseuse.
Il génère une tension continue aux bornes du condensateur C2, ce qui équivaut à deux fois l’amplitude de l’entrée sinusoïdale.
Comme la tension de sortie est le double de la valeur de crête de la tension d’entrée, ce circuit est connu sous le nom de doubleur de tension.
Cette technique peut être étendue pour générer des tensions de sortie avec des multiples plus élevés de l'amplitude de la sinusoïde d'entrée.
Les doubleurs de tension sont utilisés dans diverses applications, notamment les équipements scientifiques, le traitement du signal et les convertisseurs DC à DC dans les appareils électroniques.

circuit doubleur de tension

Voltage Doubler Circuit

Un circuit doubleur de tension intègre deux composants principaux : une section de serrage et une section redresseur. La section de serrage se compose d'un condensateur (C_1) et d'une diode (D_1), tandis que la section redresseur est équipée d'une autre diode (D_2) et d'un condensateur (C_2). Ce circuit produit une tension de sortie avec deux fois l'amplitude de la tension d'entrée sinusoïdale.
<img alt="Figure 1" src="/files/ftp_upload/15724/15724_Figure_1v2.svg" style="height: 132px;">
Le circuit commence à fonctionner lorsqu'une entrée sinusoïdale est introduite dans la section de serrage. Dans des conditions idéales, cette section génère une forme d'onde de tension aux bornes de la diode D_1, fixant efficacement les pics positifs à zéro volt et permettant au pic négatif d'atteindre une amplitude deux fois supérieure à celle de l'entrée sinusoïdale. Cette forme d'onde transformée de la section de serrage alimente ensuite la section redresseur. Ici, une transformation remarquable se produit, produisant une tension continue aux bornes du condensateur C_2. Cette tension reflète deux fois l'amplitude de l'entrée sinusoïdale initiale, fournissant l'effet de doublement qui donne son nom au circuit et marque sa fonction principale.
Le principe du doubleur de tension ne se limite pas seulement au doublement, mais peut également être adapté pour multiplier la tension d'entrée par des facteurs plus élevés, élargissant ainsi son champ d'application. Les doubleurs de tension jouent un rôle essentiel dans divers domaines, trouvant leur utilisation dans les instruments scientifiques, améliorant les techniques de traitement du signal et servant de composants essentiels dans les convertisseurs DC-DC de nombreux gadgets électroniques. Cette capacité à doubler efficacement la tension fait du circuit doubleur de tension une pierre angulaire de la conception et des applications électroniques.

Circuit doubleur de tension

Considérons un circuit de doubleur de tension composé de deux sections consécutives : une section de serrage et une section redresseuse.
La section de serrage comprend un ...

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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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voltage doubler circuit

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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