The MT8870 Tone Decoder is a kind of commonly 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.
Working voltage: 5V
Power Consumption: 500MW(MAX)r: 500 mw (MAX)
On-board voice input interface
On-board LED, it is very convenient to check the output state.