[SOLVED] problem in dtmf decoding

[Pulkit Varshney]

I want to decode the dtmf tones sent from mobile's microphone but i have stuck in this. I am not getting output. I think there may be some problem in earphones' output .. Tell me how to connect earphone to dtmf decoder's IC. I am using MT8870.

 

[chuckey]

Are you using this :- MT8870 datasheet pdf datenblatt - Mitel Networks Corporation - ISO2-CMOS Integrated DTMF Receiver ::: ALLDATASHEET :::
it says the input is on pin.
Frank

 

[Pulkit Varshney]

yes, i m using the same datasheet.
I have cutted my earphone's wire and got four wires of colour green, red, and 2 yellow. than i connected green and red wires to pin no. 2 and ground respectively and i have also tried the reverse combination. Am i doing the right or is there any other way to give input to mt 8870 ic.

 

[Pulkit Varshney]

i have attached the circuit that i am using..

 

[Pulkit Varshney]

yeahh,, i got it that how to connect mobile and ic...

 

[ramza038]

So can u kindly send me ur working circuit diagram.

 

[pratyusha m]

Hey man, I've been using a DTMF decoder CM8870, I've opened the PCB mike box, and have connected the right,left and ground wires to a male jack and then connected to a female jack and again to a male jack pin..the pin had sleeve,tip and ring..nd to sleeve, right to tip and left to ring. If your's is working, could you please send me the hardware design part of it..I'm not sure I've connected mine right..