Description:
The NTE1691 and NTE1692 are monolithic CMOS integrated circuits in an 18–Lead DIP type package that provide all the features required for implementing a pulse dialer with redial.

FEATUREs:
• Uses Either a Standard 2 of 7 Matrix Keyboard with Negative True Common or the Inexpensive Form A–Type Keyboard
• Make/Break Ratio Can Be Selected
• Redial with * or #
• Tone Signal Output or On–Chip Reference Voltage by Bonding Option on Chip
• 10pps/20pps Can be Selected

Functions:
• Mute Output Logic “0”
• Pulse Output Logic “0”
• RC Oscillation for Reference Frequency
• Designed to Operate Directly from the Telephone Line
• Used CMOS Technology for Low Voltage, Low Power Operation
• Power Up Clear Circuitry
• NTE1691 Pin2: VREF
• NTE1692 Pin2: Tone Out