【作者】 李汇； 王继安； 蔡化； 龚敏；

【Author】 Li Hui Wang Ji-an Cai Hua Gong Min (Key lab of microelectronics, College of Physical Science and Technology Sichuan University, Chengdu, 610064 China) (Chengdu Sino Microelectronics System Co.,Ltd, chengdu,610054,China)

【机构】 四川大学物理科学与技术学院； 成都华微电子系统有限公司；

【摘要】 本文在分析电流型脉宽调制原理的基础上,提出了一种适用于AC／DC和DC／DC变换的峰值电流型脉宽调制器的设计,并用cadence spectre仿真工具对关键模块电路和控制器进行了仿真分析,给出了模拟结果。该控制器内部包含振荡器, 基准电压源,误差放大器,比较器,欠压锁定电路等模块,工作频率可调,启动电流小,具有过压,欠压和逐脉冲限流保护,用其构成的开关电源,外围电路简单,所用元件少。更多还原

【Abstract】 On the basis of analyzing the principle of the current-mode pulse width modulation, a design of peak-current-mode pulse width modulator which can be used in the AC/DC and DC/DC converters is presented in the paper and the design is simulated by cadence spectre. The modulator is composed of several circuit modules, such as oscillator, voltage reference, error amplifier, comparator, under-voltage lockout circuit. It has the characteristics of low start up current, tunable frequency, over-voltage, under-voltage and pulse by pulse current limiting protection. The modulator provides necessary features to implement switching power supply with less parts and simple design of the external circuit.更多还原