Datasheet for the MC145436A, a Motorola DTMF receiver that decodes telephone touch-tone dual-frequency signals into 4-bit codes. The PDF provides pinout, crystal oscillator requirements, output timing, data valid signal behaviour and application circuits. Repair technicians working on telephone equipment, intercoms or remote control systems use it to verify the crystal is oscillating, check supply and analog input level, and observe the data outputs while sending tones, before suspecting the decoder itself.
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