The MT8870 Tone Decoder is a kind of common used multifrequency decode IC product developed by the MITEL company. It is a compete DTMF receiver. After it received the DTMF signal, it will divide the signal into high frequency group and low frequency group and send the signal to the digital decoder which can figure out the key value then send it to the outside Bus via four lines( Q1, Q2, Q3, Q4) as the binary form.
I want to interface and detect button press of EPABX line after picking of cradle.
Is this PCB is suitable for this .
Its connection diagram is available with this PCB?