Switch power supply controller and switch power supply circuit

Abstract

The invention is suitable for the field of switch power supplies, and provides a switch power supply controller which is connected with a power supply, a transformer provided with a primary side and a secondary side, and an isolated drive module. The isolated drive module receives drive signals and outputs feedback signals. The switch power supply controller comprises a feedback unit and an oscillation control unit, wherein the feedback unit samples voltage and currents output from the output side of a switch power supply and outputs the drive signals from the output end to the isolated drive module, the feedback end of the oscillation control unit is connected with the output end of the isolated drive module, an energy-storing loop of the transformer is controlled to be disconnected or connected according to the feedback signals or energy storage and demagnetization are achieved through preset frequency. By means of the oscillation control unit, the energy-storing loop of the primary side of the transformer is controlled to be disconnected or connected through the feedback signals so that the switch power supply outputs constant currents and constant voltage. Therefore, by means of the switch controller with a high integrated level, output of the constant voltage and the constant currents of the switch power supply is achieved, and the size of the switch power supply is reduced.

Description

technical field [0001] The invention belongs to the field of switching power supplies, in particular to a switching power supply controller and a switching power supply circuit. Background technique [0002] With the continuous development of switching power supply technology, switching power supplies that tend to be more and more miniaturized are more and more widely used in electronic devices such as chargers, adapters, and LED (light-emitting diode, light-emitting diode) driving power supplies. [0003] At present, there are mainly two topological structures for small and medium power switching power supplies: primary side feedback and secondary side feedback. Among them, the dynamic response of the secondary side feedback is fast, but it needs a photocoupler, a three-terminal adjustable shunt reference source (such as: TL431) and more discrete components, and the circuit structure is more complicated; while the primary side feedback does not need a photocoupler , Three-...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the embodiments of the present invention is to provide a switching power supply controller, aiming to solve the contradiction between the dynamic response of the traditional switching power supply and the degree of circuit integration

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