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DTMF DECODER IC 8870

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                                                                                                 PIN DIAGRAM 
 
FREQUENCY DETAILS

DTMF Decoder IC like CM8870 is easily available in market so I have used it ,but no problem if you get any other like KT3170 only pin name will be different.  (Refer to datasheet for standard circuit) 

 
The decoder uses digital counting techniques to detect and decode all 16 DTMF tone pairs into a 4-bit code. 
               --------------
           l              l- d3
           l     DTMF     l- d2
signal in -l    Decoder   l- d1     4-bit binary out
           l     chip     l- d0
           l              l- strobe
            -------------
 
Presented By- SANJEEV SHARMA 

  [ Studying in EC 2nd Year]
  Naraina College Of Engineering & Technology, kanpur






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