Datasheet in PDF form for the MT8888, an integrated DTMF transceiver that combines a tone receiver and a tone generator with a call-progress filter in one package, originally from Mitel and later Zarlink. Expect pinout, register and timing details, crystal requirements and application circuits for microprocessor interfacing. Technicians use it when repairing telephone equipment, alarm diallers or intercoms, checking crystal oscillation and supply pins. Confirm the exact suffix and package marked on the chip before relying on the pin numbering.
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