General Description
The HT9020 provides two modes; Call progress tone decoder and Busy redial controller, to support the application fields.

Features
• Low cost 32768Hz crystal
• Low power consumption
• Operating voltage: 2.5V to 5.5V (CPT mode)
                                 2.0V to 5.5V (ABR mode)
• Call progress tone decoder
   – Fully decoded tristate call progress status output
   – Works with traditional precision or PBX call progress tones
• Busy redial controller
   – Repeat times: 3, 10 or 15 times ( 2, 5, 15 times by mask option)
   – 4.65, 32.6 and 62.8 sec break time (16.3sec by mask option)
   – Auto-terminate after 30 times (default) ringback tone receipt