Adjustable switch power supply based on BUCK circuit

Abstract

The invention discloses an adjustable switch power supply based on a BUCK circuit. The adjustable switch power supply comprises a first linear voltage-stabilizing power supplying circuit, a low-voltage switch-off and soft-start circuit, a PWM control circuit, a constant-voltage constant-current control circuit, a bootstrap suspension driving circuit, an over-current switch-off circuit, an MOS transistor, a constant-current load circuit and a voltage and current sampling circuit. The first linear voltage-stabilizing power supplying circuit provides a voltage-stabilizing power supply of a system, the low-voltage switch-off and soft-start circuit is used for low-voltage protection and soft starting, and the bootstrap suspension driving circuit is used for driving the MOS transistor by adopting push-pull output; the constant-current load circuit is used for providing load for system output to achieve stable output of the system, the voltage and current sampling circuit is used for collecting the output voltage or current of the system, the over-current switch-off circuit is used for over-current protection, and the constant-voltage constant-current control circuit is used for feeding back and controlling the duty ratio of PWM output to adjust the output voltage or current of the system. The adjustable switch power supply outputs constant voltage and constant current and automatically conducts switching, and the output voltage and current are continuously and linearly adjustable.

Description

technical field [0001] The invention relates to a switching power supply, in particular to an adjustable switching power supply based on a BUCK circuit. Background technique [0002] With the development of electronic technology, the status of electronic equipment in people's life and production is becoming more and more important, and many electronic equipment also put forward higher requirements for the required power supply. A considerable number of electronic devices cannot directly use the AC power provided by the power grid, but need a stable DC power supply. Therefore, the requirements for the performance, volume, and weight of the DC power supply are also constantly increasing. The traditional switching power supply, because it is a fixed output, even if it is adjustable, it is fine-tuning, which is difficult to meet the requirements of modern electronic products. Contents of the invention [0003] Aiming at the defects existing in the prior art, the present inven...

AI Technical Summary

Problems solved by technology

The traditional switching power supply, because it is a fixed output, even if it is adjustable, it is fine-tuning, and it is difficult to adapt to the requirements of modern electronic products.

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