Active power factor correction circuit

Abstract

The invention discloses an active power factor correction circuit which mainly solves the problem that a peripheral inductor is large in size in the prior art. The circuit comprises a reference power supply (1), a first error amplifier (2), a multiplier (3), a comparator (4), a logic driving circuit (5), a follower circuit (6) and a zero current detector (7), wherein output reference voltage of the reference power supply (1) is connected with the first error amplifier (2); an output of the first error amplifier (2) is connected with the multiplier (3); an output of the multiplier (3) is connected with the comparator (4); an output (4) the comparator (4) and an output of the zero current detector (7) are connected with the logic driving circuit (5); the logic driving circuit (5) generates an output signal of a chip where the logic driving circuit (5) is located; the follower circuit (6) is in bridge connection between the first error amplifier (2) and the multiplier (3); current is extracted from an input end of the multiplier (3); and output voltage Vout varies with input voltage Vin. With the adoption of the active power factor correction circuit, the size of the peripheral inductor adopted by the active power factor correction circuit is reduced effectively, and the active power factor correction circuit can be applied to electronic equipment adopting the active power factor correction circuit.

Description

technical field [0001] The invention belongs to the technical field of electronic circuits, and relates to an analog integrated circuit, in particular to an active power factor correction circuit. Background technique [0002] As a very important power management circuit, active power factor correction is widely used in various electronic devices. After the active power factor correction is applied to the rectification and filtering circuit, it usually provides a power factor value close to 1. Therefore, the active power factor correction circuit can reduce the harmonic pollution of the electronic equipment to the power grid and improve the utilization rate of electric energy. Compared with the commonly used passive power factor correction circuit, it has the advantages of high power factor value and small volume. [0003] The structure of the existing active power factor correction circuit is as follows figure 1 As shown, the active power factor correction circuit is comp...

AI Technical Summary

Problems solved by technology

Since the size of the external inductor used in the active power factor correction circuit is proportional to the output voltage V OUT with input voltage V in Therefore, the size of the peripheral inductance used in the existing active power factor correction circuit is very large, which increases the volume of electronic equipment and limits the development of electronic equipment in the direction of portable

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