The DTMF Shield for Arduino converts DTMF or Touch Tone signals into a format that microcontrollers (uC) or Arduino boards can understand. DTMF tones are analog signals that Arduino and most uC cannot read directly. This module converts those signals into a digital format that uC can easily read.
Here is the functional diagram of the DTMF Shield.
The DTMF Module is specifically designed to plug right into the Arduino boards, but it can also be used with a variety of microcontrollers.
Demo of DTMF Shield for Arduino
See other demo videos here.
Note: some these videos show an earlier board version with no Arduino headers. The formal version of sale has headers to right into an Arduino board
- Operating Voltage: 5v, Current draw: 3mA
- Input signal range: 27.5 to 869mVrms (-29 to 1dBm )
- Trim pot for easy gain adjustment.
- 3.5mm stereo audio jack (TRS) and 0.1″ standard interface headers
- LED to indicate tone decoded
- Dimension: 0.79″ x 2.16″, 20mm x 55mm
- DTMF Shield User Manual
- Library and Sample Sketch: download
- DTMF Module Schematics
- Datasheet for Holtek HT9170B DTMF decoder IC
- Demo videos