Parallel MOS transistor current sharing and short circuit protection circuit

Abstract

The invention discloses a parallel MOS transistor current sharing and short circuit protection circuit, and relates to the technical fields of electronic circuits and power electronics. The parallel MOS transistor current sharing and short circuit protection circuit comprises a switching value monitoring circuit, an analog quantity monitoring circuit, a fast monitoring circuit, an MOS transistor parallel current sharing circuit, a driving circuit and a main control circuit, wherein one end of the switching value monitoring circuit is connected with the main control circuit; the other end of the switching value monitoring circuit is connected with the main control circuit and one end of the analog quantity monitoring circuit; the other end of the analog quantity monitoring circuit is connected with the fast monitoring circuit; the fast monitoring circuit is connected with the main control circuit and one end of the MOS transistor parallel current sharing circuit; and the MOS transistor parallel current sharing circuit is connected with the driving circuit and external bus voltage. The parallel MOS transistor current sharing and short circuit protection circuit realizes that each MOS transistor is equal in flowing current and switching speed, and can detect the current operating state of each MOS transistor quickly and effectively; and the parallel MOS transistor current sharing and short circuit protection circuit is simple and reliable in circuit construction and small in PCB occupation area.

Description

technical field [0001] The invention relates to the technical field of electronic circuits and the field of power electronics, in particular to a parallel MOS tube current equalization and short circuit protection circuit. Background technique [0002] The MOS tube is a Metal Oxide Semiconductor Field Effect Transistor (Metal Oxide Semiconductor FieldEffect Transistor). With the development of electronic power technology, power MOSFET has been more and more widely used for its good high-frequency performance, small switching loss, high input impedance, low driving power, and simple driving circuit. In many applications with low voltage and high power, such as electric tricycles, small electric forklifts, etc., in order to meet the current requirements, the method of parallel connection of MOS tubes is adopted without exception. However, when the MOS tubes are used in parallel, the problem of current sharing has not been effectively solved, which may damage the MOS tubes due...

AI Technical Summary

Problems solved by technology

However, when the MOS tubes are used in parallel, the problem of current sharing has not been effectively solved, which may damage the MOS tubes due to uneven current; at the same time, when the MOS tubes are used, the short-circuit protection function for the MOS tubes is rarely added Without the protection circuit of the MOS tube, the misjudgment of the protection state or the untimely response will not play a big role in the MOS tube, which will lead to the direct connection and damage of multiple parallel-connected MOS tubes, which greatly improves the research and development. cost

[0003] When the current technology is used in parallel with MOS tubes, the problem of current sharing has not been effectively solved, so that the MOS tube may be damaged due to uneven current; at the same time, when the MOS tube is used, the short-circuit protection function for the MOS tube is rarely added. Even if the protection circuit of the MOS tube is added, the misjudgment of the protection state or the untimely response will not have a great effect on the MOS tube, which will lead to the direct connection and damage of multiple parallel-connected MOS tubes, which greatly improves the performance of the MOS tube. research and development costs

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