Off-line Single-chip Ac / Dc Switching Power Supply Ic Design

Power integrated circuit is one of the most important branches of integrated circuit, including power transistor and control circuit and output drive. As the bridge of the control and execution part of the system, it plays an important role in the fields of electronic power, automatic control, communication and automotive. Because it integrated power transistor, Power IC is relatively more difficult, both in circuit design and process technology.Recent changes in electronic systems are forcing higher levels of integration in switch power supply chips. The most notable requirements are those involving size, weight and energy efficiency. New government energy-efficiency programs are further reshaping switch-power-supply designs.This paper designs an off-line power supply chip which integrated the control circuits including the oscillator, pulse width modulator, thermal shutdown, and the high voltage power transistor. At first, it introduces the development of the Power IC and the switch Power Supply. Second, all the control circuits will be analyzed and designed one by one, also the simulating wave will be given. Last, it designs the structure of the Power transistor.