This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
LM2907能实现模拟音频输入检测 转换数字输出0/1 ？输入可检范围50hz-20khz .
这是个 频率到电压的转换器. 使用很简单 VOUT = fIN × VCC × R1 × C1
这2框图，采用5V供电，输出一直是低电平，音乐输入。
