A Synchronous Rectification Module Power Supply Combining Self-Drive and External Drive Circuit

Abstract

A synchronous rectification module power supply combining self-driving and external driving circuits according to the present invention includes input filter circuit, switch circuit, transformer isolation conversion circuit, output rectifying circuit, output filter circuit, feedback circuit, control circuit, self-driving circuit and external drive circuit. The modular power supply of the present invention can effectively improve the output efficiency of the power supply, especially in low-voltage and high-current occasions, and can make the output power more reliable and stable; the drive mode combining external drive and self-drive has relatively low requirements on input conditions. relaxed for a wider input voltage range. The external drive signal and the self-drive drive signal maintain a complementary relationship. When the external drive is turned on, the self-drive is turned off; when the self-drive is turned on, the external drive is turned off, which can effectively prevent the rectifier and freewheeling tube open, a short circuit occurs.

Description

technical field [0001] The invention relates to the field of electronic circuits, in particular to a synchronous rectification module power supply combining self-driving and external driving circuits. Background technique [0002] With the development of the module power supply, the usage of the module power supply in all walks of life is increasing year by year. There are different ways to use the module power supply, and there are various requirements for the performance of the module power supply. In order to adapt to the current market conditions, the design of the module power supply mainly considers the following points, such as the development of the input range of the module to wide input, the development of the output of the module to low voltage and high current, the efficiency of the module to be high, and the development of the module to miniaturization, etc. . Based on the above conditions, the currently used modular power supply usually includes an input filte...

AI Technical Summary

Problems solved by technology

However, the electronic components in the module power supply will be affected by electromagnetic interference, causing the feedback signal generated by the feedback unit to be unstable

For example, the high-frequency electromagnetic waves generated by the transformer will interfere with the conduction and cut-off of the MOS tube, resulting in a longer conduction time of the MOS tube, which will cause a large increase in the current flowing through the primary coil of the transformer, thus making the feedback signal Change from a low-level signal to a high-level signal

The instantaneous high-level signal will cause the control unit to make wrong adjustments to the duty ratio of the pulse voltage, which will not only cause the output voltage of the power module to be unstable, and the circuit power loss will be large, but also the circuit is more complicated and difficult to miniaturize

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