The Si3226 and Si3227 include the voice codecs, DTMF detection, and signal generation functions needed for two complete analog telephone interfaces. All the BORSCHT functions are supported as well.

Figure out which tones are playing, and you’ve decoded the signal. Anyway, you can get DTMF decoder chips for pennies on eBay, and they make a great remote-control interface for a simple robot ...

The Sycurio patents at issue concern Sycurio’s DTMF (Dual-Tone Multi-Frequency) masking technology which provides a secure method for processing credit and debit card payments by telephone in ...

Low battery detection and automatic low battery disconnect. Telephone line supervision and reporting. Caller ID, calling name and DNIS. Communicates in all major ITI formats, all common pulse formats, ...