Analog Switches
Digital waveform can easily be switched using a multiplexer logic element. The digital multiplexer simply gates the appropriate select and data signals together and generates a digitally “perfect” output corresponding to the input channel. No data bits are lost because this is digital circuitry. Multiplexing analog signals, unfortunately, is not this easy. Noise and distortion can be introduced by the analog switching element. So efforts have been made produce linear, low-distortion analog switches.