TP5088

TP5088 DTMF Generator for Binary Data October 1991 TP5088 DTMF Generator for Binary Data General Description This CMOS device provides low cost tone-dialing capability in microprocessor-controlled telephone applications 4-bit binary data is decoded directly without the need for conversion to simulated keyboard inputs required by standard DTMF generators With the TONE ENABLE input low the oscillator is inhibited and the device is in a low power idle mode On the low-to-high transition of TONE ENABLE data is latched into the device and the selected tone pair from the standard DTMF frequencies is generated An open-drain N-channel transistor provides a MUTE output during tone generation Features Y Y Y Y Y Y Y Y Y Y Direct microprocessor interface Binary data inputs with latches Generates 16 standard tone pairs On-chip 3 579545 MHz crystal-controlled oscillator Better than 0 64% frequency accuracy High group pre-emphasis Low harmonic distortion MUTE output interfaces to speech network Low power idle mode 3 5V – 8V operation Block Diagram TL H 5004 – 1 Crystal Specification Parallel Resonant 3 579545 MHz RS s 150X L e 100 mH C0 e 5 pF C1 e 0 02 pF C1995 National Semiconductor Corporation TL H 5004 RRD-B30M115 Printed in U S A Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage (VDDbVSS) MUTE Voltage Maximum Voltage at Any Other P...