General Description
The HT9200A/B tone generators are designed for µC interfaces. They can be instructed by a µC to generate 16 dual tones and 8 single tones from the DTMF pin. The HT9200A provides a serial mode whereas the HT9200B contains a selectable serial/parallel mode interface for various applications such as security systems, home automation, remote control through telephone lines, communication systems, etc.
   
Features
• Operating voltage: 2.0V~5.5V
• Serial mode for the HT9200A
• Serial/parallel mode for the HT9200B
• Low standby current
• Low total harmonic distortion
• 3.58MHz crystal or ceramic resonator