| This paper is supported by the research project of"Theoretical research and design of key techniques for deep-submicron power management IC"of the Institute of Electronic CAD. Aiming at AMOLED power supply, a synchronous Boost DC-DC converter with fast transient response, based on peak-current mode control is presented. The system with integrated power switch and synchronous rectifier needs fewer external components, while the 1.6MHz switching frequency makes the external components small in size. At the premise of stability, by setting a proper bandwidth, the circuit provides a fast transient response with small overshoots. Zero current detection and anti-ring circuit increase reliability of the system. Simulated by Hspice, the results show that all functions and specifications are met.The paper starts with the principles of BOOST DC-DC converter, and discusses the effects of devices on system efficiency and output ripple. From the application environment and electrical characteristics of the system, block functions and control method are determined. By calculating the frequencies of poles and zeros of the system, frequency compensation strategy is proposed. From the simulation results, it can be seen that the bandwidth is 55KHz and phase margin is 58°, which means the system can work stably. Then, sub-block circuits are designed and some important circuits like error amplifier, pwm comparator, power stage circuits are analyzed in detail. At last, some simulation waveforms of the whole system are given.
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