What Is a Voltage Doubler?
Voltage doubler rectification. In some places where high voltage and small current are required, voltage doubler rectifier circuits are often used. Voltage doubling rectification can use a lower AC voltage to "rectify" a higher DC voltage with a rectifier diode and capacitor with a higher withstand voltage. The voltage doubler rectifier circuit is generally divided into double voltage, triple voltage and multiple voltage rectifier circuits according to how many times the output voltage is the input voltage.
Voltage doubling rectification
- Chinese name
- Voltage doubling rectification
- category
- Physical term
- working principle
- Diode Rectification and Guidance
- Voltage doubler rectification. In some places where high voltage and small current are required, voltage doubler rectifier circuits are often used. Voltage doubling rectification can use a lower AC voltage to "rectify" a higher DC voltage with a rectifier diode and capacitor with a higher withstand voltage. The voltage doubler rectifier circuit is generally divided into double voltage, triple voltage and multiple voltage rectifier circuits according to how many times the output voltage is the input voltage.
- The circuit consists of a transformer B, two rectifier diodes D1, D2, and two capacitors C1, C2.
- It works as follows:
- On the basis of the double-voltage rectifier circuit, a rectifier diode D3 and a filter capacitor C3 are added to form a triple-voltage rectifier circuit. The working principle of the triple-voltage rectifier circuit is: The second half cycle is the same as the double voltage rectification circuit, that is, the voltage on C1 is charged to close to 2E2, and the voltage on C2 is charged to close to 22E2. When the third half of the week, D1, D3 are turned on, D2 is turned off, in addition to charging C1 via D1, and charging C3 via D3, the charging voltage on C3 Uc3 = e2 peak + Uc2-Uc122E2 At RFZ, the DC voltage Usc = Uc1i + Uc332E2 can be output to achieve three times the voltage rectification.
- Triple voltage rectifier circuit
- In this way, adding multiple diodes and the same number of capacitors can form a multi-voltage rectifier circuit, as shown in the three-voltage rectifier circuit. When n is an odd number, the output voltage is taken from the upper end: when n is an even number, the output voltage is taken from the lower end.
- It must be noted that the voltage doubler rectifier circuit can only work under a light load (ie, Rfz is large. The output current is small), otherwise the output voltage will decrease. The higher the voltage doubler, the more obvious the situation that the output voltage drops due to the increase of the load current.
- The maximum reverse voltage of the diode used in the voltage doubler rectifier circuit should be greater than. Available high-voltage silicon rectifiers, its series model is 2DL. Such as 2DL2 / 0.2, it means that the highest reverse voltage is 2 kV and the average rectified current is 200 mA. The capacitor used in the voltage doubler rectifier circuit is relatively small, and no electrolytic capacitor is needed. The withstand voltage of the capacitor must be greater than 1.5x, and it is safe and reliable in use.