High-frequency transformer common-mode noise testing method

Abstract

The invention relates to a high-frequency transformer common-mode noise testing method. The method specifically comprises the steps that a transformer is independently split out, common-mode noise of the high-frequency transformer is judged through a common-mode noise testing circuit, the testing circuit is a square-wave generator composed of an NEC555 main circuit and an external circuit, the transformer and a driving and detection circuit for signals of the transformer. The method is used for high-frequency transformer common-mode noise interference test, during testing, the common-mode noise generated by the transformer body can be known only by testing pins of the transformer bod, and during actual application, a common-mode noise amplitude value of a power source body can be basically judged only by testing a common-mode noise amplitude value of the transformer body; in other words, the method can provide quite reliable testing method and means for the front end of the final testing of power source common-mode noise, is of a great significance in power source quality control, and can generate large economic benefits.

Description

technical field [0001] The invention relates to a method for testing common-mode noise of a high-frequency transformer, which belongs to the field of power supply equipment. Background technique [0002] Ordinary high frequency transformer working circuit, such as figure 1 As shown, the circuit is mainly composed of two parts: bridge module and transformer signal drive and detection, which transfer energy to the secondary output through the winding of the transformer. Due to structural defects in this circuit, it is difficult to control the size of the common-mode noise of the high-frequency transformer. [0003] For the common-mode noise of high-frequency transformers, it seriously affects the use of mobile phones and tablet computers. The signal of common-mode noise transmits small signals to the ground through the touch screen and hand or stylus. This path will affect the practicality of mobile phones and tablets. Cause serious interference, most power transformers have...

AI Technical Summary

Problems solved by technology

Due to structural defects in this circuit, it is difficult to control the magnitude of the common-mode noise of the high-frequency transformer

[0003] For the common-mode noise of high-frequency transformers, it seriously affects the use of mobile phones and tablet computers. The signal of common-mode noise transmits small signals to the ground through the touch screen and hand or stylus. This path will affect the practicality of mobile phones and tablets. Cause serious interference, most power transformers have no clear and reliable method to test common mode noise, resulting in a lot of waste of manpower and material resources in the R & D and design stage to optimize the design of high-frequency transformers, and the optimally designed transformers may not fully meet the noise requirements Requirements, there is an urgent need for a high-precision method to test the noise, and at the same time give practical guidance to engineers

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