[SOLVED] Problem With MT8870 IC

[agarwal.rishabh20@gmail.c]

I am using MT8870 DTMF decoder IC in my project. I have connected the components as in the datasheet.

I have connected a mobile unit's headset also. Everything is done.
!!!!
The problem is, the ic is not at all detecting any tones and the output pins always show as follows:

STD- HIGH
Q3- Low
Q2- Low
Q1- Low
Q0- Low


Hope I find the solution asap....
Please help me

---------- Post added at 14:30 ---------- Previous post was at 12:41 ----------

Please.. someone showup.. need help.

 

[agarwal.rishabh20@gmail.c]

Now I got the output while using the same components on a breadboard but when I soldered them, its again stopped working.

Help me

 

[Santosh13]

After rigging up the circuit and calling form the remote mobile did you press the keys on the remote mobile eg:2,4,6,8 etc...
Then you can notice changes in Q3-Q0...

hope you find this useful

 

[agarwal.rishabh20@gmail.c]

Yeah got the output.... and even the above mentioned problem is solved

 

[Santosh13]

Good Luck

 

[ramza038]

I am doing the same project as u. But i can't get output. Can u kindly share me ur working circuit diagram.