08-16-2017, 09:44 PM
CMOS Integrated DTMF Receiver
Features
Full DTMF receiver
Less than 35mW power consumption
Industrial temperature range
Uses quartz crystal or ceramic resonators
Adjustable acquisition and release times
18-pin DIP, 18-pin DIP EIAJ, 18-pin SOIC, 20-pin
PLCC
CM8870C
Power down mode
Inhibit mode
Buffered OSC3 output (PLCC package only)
CM8870C is fully compatible with CM8870 for 18-pin
devices by grounding pins 5 and 6
Applications
PABX
Central office
Mobile radio
Remote control
Remote data entry
Call limiting
Telephone answering systems
Paging systems
Product Description
The CAMD CM8870/70C provides full DTMF receiver capability by integrating both the bandsplit filter and digital decoder functions into a single 18-pin DIP, SOIC, or 20-pin PLCC package. The CM8870/70C is manufactured using state-of-the-art CMOS process technology for low power consumption (35mW, max.) and precise data handling. The filter section uses a switched capacitor technique for both high and low group filters and dial tone rejection. The CM8870/70C 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 amplifier, 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.
For more information about this article,please follow the link:
http://googleurl?sa=t&source=web&cd=1&ve...CM8870.pdf&ei=au67TPzhJYWmcLzR-aAP&usg=AFQjCNHw0OEuiyIWGqm2BzYDiIsZa_h3Ug