Battery charging circuit and method thereof

Abstract

The invention provides a battery charging circuit. The battery charging circuit is characterized in that the structure of a feedback control circuit in the conventional battery charging circuit is simplified; the differential value adjustment between a feedback signal and a reference signal is realized by adopting a comparator; a feedback control signal of a logical level form is output to realize automatic switching among feedback control circuits, so that the phenomena of error switching and simultaneous working of a plurality of feedback control circuits can be effectively avoided, and high circuit portability is achieved. Meanwhile, a control way of switching on in a fixed-duration or switching off in a fixed duration is adopted, so that the circuit structure is easy to integrate.

Description

technical field [0001] The present invention relates to an electronic circuit, and more particularly, the present invention relates to a battery charging circuit and method thereof. Background technique [0002] Due to the diversification of power supply and battery types, the battery charging circuit needs to control multiple variables such as output voltage, output current, input voltage and input current. figure 1 A schematic circuit structure diagram of a conventional battery charging circuit 10 using a BUCK circuit is shown. The battery charging circuit 10 includes multiple control loops such as output voltage, output current, input voltage, and output current, and each control loop includes an error amplifier and a compensation network. Taking the working of the output voltage control loop as an example, in each switching cycle, the clock signal CLK sets the RS flip-flop to output the switching control signal PWM to turn on the pull-up power transistor PM1, and simult...

AI Technical Summary

Problems solved by technology

And because different circuit parameters require different compensation networks, figure 1 The battery charging circuit shown is not very portable

At the same time, because the signal values ​​of the error amplification signals Vcom1~Vcomn output by each control loop are relatively close, there may be problems in switching between control loops, for example, there may be multiple control loops working at the same time, or the loop Road switching error, etc.

Images