The WTV020SD is a small, simple IC for embedding audio-playback into your next project. These devices are commonly used in children’s toys and “talking” retail displays. This breakout board allows you to access the functionality of the WTV020SD to give a voice to your next project.

The breakout board includes a battery connector and a micro-SD card slot. Simply load your audio files onto a micro-SD card and plug it in, power up the module and trigger the playback. Playback can be triggered in either key or serial mode:

The key-mode provides a stand alone operation where a host micro is not required. With only 3 push buttons, a 3V battery and a speaker, an extremely compact and low component count MP3-Player like system can be implemented.

The serial-mode provides a simple, 2-wire interface to any micro-controller via its DATA and CLK lines. Audio operations such as PLAY, PAUSE, STOP and VOLUME control functions are all available to the host micro via simple serial commands.

The audio compression used in this module is a little strange (4-bit ADPCM @ 6-32kHz) so you’ll need to download the utility in the documents below in order to convert your .WAV files into the 4-bit ADPCM format required.

Features:

Low-cost module for all embedded Audio-Sound applications.
Supports 4-bit ADPCM (.ad4) file formats with sampling rates from 6Khz to 36Khz.
Two operation modes:
Serial Mode: Supports a 2-Wire (Data, Clock) interface to any micro-controller.
Key Mode: Supports a simple stand alone operation without a host micro.
Differential 2 line PWM output for direct speaker connection (8 Ohm/0.5W).
Dedicated 16-bit DAC/PWM audio output to use with an external amplifier.
On-board micro-SD memory card adaptor for storing of audio, voice and music files (up to 512 files).
Supports 64Mb to 2Gig micro-SD memory cards (FAT format).
Low Power Idle current of 8.0uA
RoHS Compliant