Introduction to the common parameters of the step-down DC socket
Release time：2018-08-02 Clicks： Click
Among the many DC sockets in use, there is a kind of Buck DC socket is not often used, but there are friends to consult, we will explain to you.
The transformer free insulated socket switch is the simplest circuit structure in the socket switch. Part of the input and output of the power supply is common, and the input and output can not be isolated. Its application scope is limited, but because there is no transformer, so the working principle of this kind of socket power supply is easy to understand, there will be no transformer leakage inductance caused by the fault. The buck outlet switch (that is, the buck DC regulator) is one of the non isolated switching mode power supplies. The so-called buck type refers to whether the input voltage is positive or negative, the output voltage is always lower than the transmission voltage. Therefore, the step-down type socket switch is more suitable for use in a small and efficient socket switch voltage regulator.
Here is an example of a buck DC regulator.
The main technical indexes are as follows.
(1) the transmission voltage: 20-70V DC.
(2) output voltage: 0-25V DC.
(3) the maximum output current: 10A.
(4) conversion efficiency: greater than 70%.
(5) output ripple: less than 20mV.
The principle of step-down socket switching regulator is mainly composed of main circuit, control and drive circuit and protection circuit. The main circuit consists of the power field effect tube VT1, the power diode VD5 filter inductance L1 and the filter capacitor C10. The control and drive circuit is composed of the UC3845 current controlled chip and the pulse transformer T1 and other peripheral circuits produced by A Morimi semiconductor company. The protection circuit mainly includes the buffer network composed of R1, C2 and VD1. A current protection circuit consisting of a current transformer T2, a diode VD2, etc.