CM8870-PI, CMOS Integrated DTMF Receiver/Decoder, 18-DIP, California Micro Devices

The CM8870PI provides full DTMF receiver capability by integrating both the bandsplit filter and digital decoder functions into a single 18-pin DIP. The filter section uses a switched capacitor technique for both high and low group filters and dial tone rejection. The CM8870 decoder uses digital counting techniques for the detection and decoding of all 16 DTMF tone pairs into a 4-bit code. This DTMF receiver minimizes external component count by providing an on-chip differential input ampli-fier, clock generator, and a latched three state interface bus. The on-chip clock generator requires only a low cost TV crystal or ceramic resonator as an external component.

Technical Datasheet (235 KB)  

• Full DTMF receiver
• Less than 35mW power consumption
• Industrial temperature range
• Uses quartz crystal or ceramic resonators
• Adjustable acquisition and release times