DC surge suppression circuit based on NMOS tube

Abstract

The invention provides a DC surge suppression circuit based on an NMOS tube. The DC surge suppression circuit comprises a spike pulse suppression circuit, a voltage stabilizing circuit, a bootstrap boost circuit, a control module and an electronic switch. The spike pulse suppression circuit is connected with the output end Vin of the power supply and is used for suppressing + / -250V spike pulse voltage; the voltage stabilizing circuit is connected with the bootstrap boost circuit to provide power supply voltage for a 555 timer of the bootstrap boost circuit; the bootstrap boost circuit is connected with the electronic switch to ensure that an NMOS tube of the electronic switch can be normally conducted at normal voltage; and the control module is connected with the electronic switch to control the conduction and cut-off of an NMOS tube of the electronic switch. Compared with a PMOS, the surge suppression circuit based on the NMOS has the advantages that the reliability is high, the circuit needs to bear high voltage of more than 250V, the selectivity of the NMOS is more, the price of the PMOS is generally higher, the price of the NMOS tube is low, and the manufacturing cost is reduced.

Description

technical field [0001] The invention relates to the field of surge voltage suppression, in particular to a DC surge suppression circuit based on an NMOS transistor. Background technique [0002] For some specific environments and purposes of electrical equipment, the power supply is often accompanied by surge voltage impacts, especially for military vehicles, it is necessary to add a surge suppression module to the input front of the power module of the electrical equipment to protect the subsequent circuits, mainly The 40V / 50ms and 100V / 50ms surge voltage and ±250V peak pulse voltage stipulated in the "GJB298-87 Military Vehicle 28 Volt DC Electrical System Characteristics" standard are suppressed within the normal operating voltage range, thereby realizing the surge of military vehicles The function of voltage suppression and peak pulse voltage suppression prevents damage to electrical equipment due to the failure of the power module caused by the abnormal operation or mal...

AI Technical Summary

Problems solved by technology

[0003] In the existing surge suppression circuit, TVS transient diodes or varistors are often used in civilian applications to suppress surge voltage, but their reliability is poor.

In a surge suppression power supply module of patent CN 206542180 U, PMOS is mainly used as a control switch. Although the circuit structure of surge suppression based on PMOS is relatively simple, the price of PMOS on the market is generally high, the reliability is poor, and it is very Few PMOS can withstand high voltage above 250V

At present, most of the military uses the imported surge suppression chip LT4363, while the price of domestic surge suppression chips is generally higher

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