摘要
提出了一种采用单比较器变步长反馈控制和占空比抖动方法的数字 DC- DC变换模块 .它用 6位二进制分辨率占空比的 PWM信号实现了 7位的电压分辨率 .变步长反馈控制的使用使得它具有比恒定步长方案更好的动态性能 ,而且没有过多增加控制器的复杂度 .在 1MHz的开关频率下 ,控制器自身功耗小于 0 .5 m W(不含功率开关及驱动部分 ) .由于电路的模拟部分极少 ,因此易与数字系统进行单芯片集成 .
A digital control DC-DC converter is presented,which uses a single comparator.It adopts variable step feedback algorithm and duty cycle dither,and obtains 7 bits voltage resolution with PWM signal of only 6 bit binary duty cycle.Because of the variable step feedback algorithm,this converter has better dynamic performance than those with constant step,and has low complexity.This converter works at a switching frequency of 1MHz,and the controller's power consume is less than 0 5mW.It is suitable to be integrated with other digital systems for its small portion of analog circuit.
关键词
数字控制器
变步长反馈
占空比抖动
digital controller
variable voltage-step feedback
duty cycle dither
