在RISC机中实现D/A转换的PWM方法

PWM Method of D/A Conversion is Achieved in RISC Microcomputer

介绍了一种用8位精简指令集计算机(Recluced Instraction Set Computer,RISC)结构单片机中将PWM波转换为模拟电压输出的D/A转换的实现方法。分析了脉宽调制(PWM)频率、占空比调节精度和积分器之间的关系。在此基础上设计出一种使用AVR系列单片机MEGA16内部定时/计数器产生PWM信号,再利用通用电路把PWM信号转换成直流电压信号的硬件电路。其最大线性误差只有0.5%,且成本低廉。

A method of D/A conversion is introduced. With a 8-bit RISC structure single chip microcomputer, a PWM wave is converted to an analog voltage signal. This relationship between the PWM frequency, duty cycle a general circuit. The circuit has a maximum linearity error of only 0.5% and the cost is very low.