Circuit Project Electronic

That circuit uses the MSM6322GSK which is only available in small 24 pin plastic SOP style package. A speech pitch converter IC that operates in real time and requires very few external components. It has a microphone preamplifier and line level input and the output requires only a single transistor to directly drive a loudspeaker. As well as the microphone preamplifier, the IC contains a 4th order low pass filter on input and a 3rd order low pass filter on output. In addition there is a build-in 8-bit A/D converter and 9-bit D/A converter. [...]

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