数字化语音存储与回放系统，　　该系统主要由语音收集、增益放大、带通滤波、A\D、D\A转换，51单片机、外部RAM存储、功率放大、扬声器几大部分组成。其中语音收集主要由驻极体话筒实现。然后同过增益放大部分将几十毫安的信号放大至0~8A左右。再利用带通滤波滤去带声外地噪音，并由A\D转换将声音信号转化为数字信号存储在单片机的外部存储器中，可存储时长为4秒左右。再由D\A转换转变为模拟信号后通过带同滤波滤去噪声，功率放大部分放大功率后，最后由扬声器输出。-Digital voice storage and playback system, the system is mainly collected by the voice, gain, band-pass filter, A \ D, D \ A conversion, 51 single, external RAM storage, power amplifier, speakers of several major components. Which collected mainly by the electret microphone voice to achieve. Then gain amplification section with over tens of milliamps signal amplification to 0 ~ 8A or so. Then filtered using band-pass filter the noise with the sound field by the A \ D conversion of sound signals into digital signals stored in the microcontroller' s external memory, can be stored at 4 seconds. By the D \ A converted into analog signal filtered through the noise with the same filter, power amplifier part of the amplification power, the final output from the speaker.