Magnetic isolating feedback circuit containing voltage signal and current signal of switch power supply

Abstract

The invention relates to a switch power supply, in particular to a magnetic isolating feedback circuit containing a voltage signal and a current signal of the switch power supply. The invention provides the magnetic isolating feedback circuit containing the voltage signal and the current signal of the switch power supply. The circuit comprises an output voltage comparison unit, a magnetic isolating feedback unit, a transformer demagnetization unit and a pulse width modulation and comparison unit. The magnetic isolating feedback circuit has the advantages that: the circuit is simple; used components are reduced; feedback signals comprise a voltage signal and a current signal; a double-ring control can be implemented; the application range is wide and the circuit can be extensively applied to places with requirement on the magnetic isolating feedback; and the resistance to irradiation and interference is strong.

Description

Technical field [0001] The invention relates to a switching power supply, in particular to a switching power supply magnetic isolation feedback circuit including voltage and current signals in the switching power supply. Background technique [0002] There are currently two isolation feedback methods for switching power supplies: optocoupler isolation feedback and magnetic isolation feedback. The optocoupler isolation feedback method relies on the linear working area of ​​the optocoupler to isolate and feedback the output voltage error signal to the primary side controller to adjust the pulse width, and then realize the overall power supply voltage regulation control. The disadvantage of this feedback method is that the linear working area of ​​the optocoupler needs to be used for isolation feedback, and the transmission ratio of the optocoupler device in the linear working area is prone to drift with temperature and time, and its ability to resist radiation is poor. These will ...

AI Technical Summary

Problems solved by technology

[0004] 1. Many devices are used, the circuit is complicated, and the cost is high;

[0005] 2. There are many compensation links, and the debugging cycle is long;

[0006] 3. The total anti-radiation dose of UC1901 is low, which does not meet the application requirements of long-life spacecraft

[0007] There are also discrete devices used to replace UC1901 for magnetic isolation feedback, but often the circuit is more complex, there are more devices, and the feedback information is only the output voltage, not including the current information

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