Power supply circuit, circuit board and switching power supply

Abstract

The invention discloses a power supply circuit, a circuit board and a switching power supply. The power supply circuit comprises a first input end, a second input end and an input circuit; the input circuit is provided with a first loop and a second loop connected with the first loop, the first loop is connected with the first input end, the second loop is connected with the second input end, andthe direction of first equivalent current of the first loop is opposite to that of second equivalent current of the second loop. Thus, the direction of the first equivalent current of the first loop is opposite to the direction of the second equivalent current of the second loop, so that an induced magnetic field caused by the first equivalent current and an induced magnetic field caused by the second equivalent current can play a role in counteracting each other, and the intensity of an interference magnetic field generated by the whole power supply circuit can be reduced; therefore, the influence of the power supply circuit on the peripheral electronic equipment is reduced, and normal operation of other electronic equipment is ensured.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a power supply circuit, a circuit board and a switching power supply. Background technique [0002] The rapid development of the automobile industry and the fierce competition in the automobile market have greatly promoted the wide application of various electrical, electronic and information equipment in automobiles. With the continuous increase in the number and types of automobile electrical equipment and the continuous increase in operating frequency, The electromagnetic environment is becoming increasingly complex. At the same time, the electronic equipment and devices on the car, especially the semiconductor logic devices are very sensitive to electromagnetic interference, and mutual interference of electronic devices inside the car often occurs. When electromagnetic interference occurs, it may cause degradation of the function of the sensitive electronic equipment affected by the ...

AI Technical Summary

Problems solved by technology

When electromagnetic interference occurs, it will cause the degradation of the function of the sensitive electronic equipment affected by the interference, or cause its function to fail, which will seriously affect the safe driving of the car.

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