With the social development of information science, the production of charger is gradually improved. Now it is emphasized energy conservation and environmental protection which is good for the living conditions of future generations. How to make a kind of low power, easy to carry, high charge efficiency is becoming a discussion topic for researchers in various countries in the world.
This article mainly discuss step-up circuit and step-down circuit of charger which is made for mc34063 chip. First it can judge the power of the external voltage through oscillator circuit. If the power of the external voltage is less than five point four volt, then step-up circuit is selected by default during charging. If the power of the external voltage is more than five point four volt, the oscillator circuit is working, circuit switch to the step-down circuit is charging function. The speed of charging is fast and internal components use up less energy. In this paper, the design process to do the following two main areas of work. First it need to discuss and select the system design program, second it need to think about how to design ant how to weld in the board.
Keywords: MC34063 Chip, Step-up Circuit, Step-down Circuit, Automatic Switching Circuit, Feasibility
