Research And Design Of Core Blocks In DC/DC Power Modulator

The Switch Mode Power Supply is honored as "new highly energy-efficient power ", it is representing switch power supply's development direction. Switch Mode Power Supply has some features, such as high efficiency, wide output of Regulators range, small size, light weight and so on. , and the power source efficiency may achieve above 75% , more than the Linear Regulated Power Supply nearly one time. Along with Power Supply Technology's development, the switch mode power is developing towards the direction of miniaturization, high frequency and integrated. The high efficiency switch power is appearing more and more widespread application, particularly in portable electronic installation.This article firstly introduced the basic principles of the switch mode power, then compared the voltage control mode with the current control mode,PWM and PFM to decide the whole topology of the chip . This chip designed was a high performance fixed-frenquency current-mode pulse width modulation controller with 1.8um bilopor technology. It was specially high performance fixed frequency current mode controllers that specifically designed for off-line and dc-to-dc converter applications offering the designer a cost effective solution with minimal external components. These integrated circuits feature a trimmed oscillator for precise duty cycle control, a temperature compensated reference, error amplifier with high gain, current sensing comparator, and a high current totem pole output ideally suited for driving a power transistor.Basing on the completion of the principle analysis and circuit design ,we simulated all core blocks using Spectre and Hspice, software. The simulation results meeted the requirements and the circuit principles have been verified.