Description

MT8870 DTMF Speech Decoding Module

The MT8870 DTMF Decoder Module is a compact and efficient board designed to decode DTMF (Dual Tone Multi-Frequency) signals — the tones generated by a telephone keypad. It converts audio signals into corresponding 4-bit digital outputs, making it ideal for remote control, telephone-based automation, and DTMF-controlled robotics using Arduino or Raspberry Pi.

Features

• Based on the MT8870 DTMF decoding IC
• Converts DTMF audio tones into 4-bit binary digital signals
• Built-in operational amplifier for signal conditioning
• LED indicators for tone detection and data output
• Simple 5-pin interface (VCC, GND, D0–D3, and STQ)
• Compatible with Arduino, ESP32, and microcontroller platforms

Specifications

• Operating Voltage: 5V DC
• Detection Method: Dual Tone Multi-Frequency (DTMF)
• Output Format: 4-bit binary digital
• Frequency Range: 697 Hz – 1477 Hz
• Dimensions: 35 mm × 25 mm (approx.)
• Main IC: MT8870DE

Applications

• DTMF-controlled robots
• Telephone-based remote switching systems
• Wireless control using GSM or mobile networks
• Home automation projects
• Audio signal decoding and telecommunication training

Why Choose This Module

Compact, affordable, and highly reliable — the MT8870 DTMF Module is perfect for projects that require tone-based control or remote activation through phone signals.