1. Product features
◆ The product is a WTV020 chip external SD card module that supports 32M～1GBit capacity cards;
◆ Support FAT file system, SD card as storage carrier;
◆ Support playing WAV and 4Bit ADCPM format files;
◆ Support automatic folder recognition and voice file playback;
◆ Can play background music and interstitial advertising slogans;
◆ Control methods include button control, two-wire control and UART232 serial port control;
◆The WTV main control chip is available in WTV020-16SOP and WTV020-20SOP packages, both of which are compatible;
◆ It can play any segment of voice;
◆ Working voltage: DC2.6～3.6V;
◆ The storage contents are classified by folders for easy operation.

2. Product overview
WTV020 external SD card voice module, the main control chip selects WTV020-16S and WTV020-20S packaged chips.
The voice content update is directly replaced on the PC through the SD card reader.
The control method is also changed in a TXT file stored in the SD card.
The module supports the FAT file system.
Support WAV and ADPCM file playback.
Support two-wire serial port control mode, button mode and UART232 serial port mode.
It can automatically recognize the voice sampling rate and voice file format.