WT2605B05 Bluetooth Audio Module
Dual‑Mode Bluetooth 5.0 with AT Command Control, Built‑in 1W Amplifier & MP3 Playback
The WT2605B05 is a high‑performance dual‑mode Bluetooth 5.0 audio module designed for wireless audio and MP3 playback applications. It features a 16‑bit DAC with 95dB SNR and a 16‑bit ADC with 90dB SNR for pristine audio quality. With a built‑in 1W Class‑D amplifier, AT command UART control (115200 baud), and support for SPI‑Flash, TF card, and USB drive storage, it is the ideal solution for Bluetooth speakers, car audio, and smart home devices.
- Dual‑mode BT 5.0 – audio + BLE
- AT command control – simple UART interface
- Built‑in 1W amp – direct 8Ω speaker drive
- 16‑bit DAC – 95dB SNR for superior output
- MP3 / WAV playback – local storage support
Key Features
Audio & Bluetooth Specifications
| Parameter | Value |
|---|---|
| DAC Resolution | 16‑bit |
| DAC SNR | 95 dB (A‑Weighted) |
| DAC THD+N | ‑65 dB |
| DAC Output Swing | 0.54 Vrms |
| ADC Resolution | 16‑bit |
| ADC SNR | 90 dB (A‑Weighted) |
| Sample Rates | 8, 11.025, 12, 16, 22.05, 32, 44.1, 48 kHz |
| Bluetooth Version | 5.0 (BR/EDR + BLE) |
| Bluetooth Profiles | A2DP, AVRCP, HFP, SPP, GATT |
| RF Output Power | +2 dBm (typical) |
| Audio Formats | MP3, WAV |
| Storage Media | SPI‑Flash (128Mbit), TF (32GB), USB (32GB) |
| Amplifier Output | 1W @ 8Ω (Class‑D) |
| Crystal | 24MHz, 12pF, ±10PPM |
| Module Size | See packaging section |
AT Command Highlights
| Command | Function | Description |
|---|---|---|
| AT+PLAY | Playback | Play audio from current storage |
| AT+STOP | Stop | Stop current playback |
| AT+NEXT | Next Track | Play next track |
| AT+PREV | Previous Track | Play previous track |
| AT+VOL | Volume Control | Set volume level (0–31) |
| AT+CHMODE | Mode Switch | Switch between Bluetooth and audio mode |
| AT+PLAYFILE | File Playback | Play by filename |
| AT+PLAYFOLDER | Folder Playback | Play by folder + index |
| BT_STA | Bluetooth Status | Auto‑returns connection status (6=connected, 9=disconnected) |
Default baud rate: 115200. The module defaults to Bluetooth mode on power‑up. Use AT+CHMODE to switch to audio mode for local playback from Flash/TF/USB.
Technical Specifications
| Parameter | Value / Condition |
|---|---|
| Package | 20‑pin module |
| Processor | 32‑bit DSP |
| Operating Voltage | 2.8V – 5.0V |
| DAC SNR | 95 dB (A‑Weighted) |
| ADC SNR | 90 dB (A‑Weighted) |
| Audio Formats | MP3, WAV |
| External Storage | SPI‑Flash (128Mbit), TF (32GB), USB (32GB) |
| Control Interface | UART (AT commands, 115200 baud) |
| Volume Levels | 32 (0–31) |
| Bluetooth | 5.0, dual‑mode (BR/EDR + BLE) |
| Bluetooth Name | BT_WT2605C (default) |
| Crystal | 24MHz, 12pF, ±10PPM |
| Amplifier Output | 1W @ 8Ω (Class‑D) |
| Amplifier Channels | Stereo (ROUT + LOUT) |
| Operating Temperature | ‑40°C ~ +85°C |
| Storage Temperature | ‑65°C ~ +150°C |
Pin Functions (20‑Pin Module)
| Pin | Name | Function |
|---|---|---|
| 2 | SD_CMD | SD card chip select |
| 3 | ROUT | Internal amplifier right channel output |
| 4 | LOUT | Internal amplifier left channel output |
| 5 | DACR | DAC right channel output |
| 6 | DACL | DAC left channel output |
| 9 | MIC‑IN | Microphone input |
| 10 | GND | Ground |
| 11 | CS / P14 / BUSY | Busy signal output |
| 12 | TXD | UART transmit |
| 13 | RXD | UART receive |
| 14 | SD_CLK | SD card clock |
| 15 | ADKEY / P06 | Analog key input / GPIO |
| 16 | VCC33 | 3.3V power output |
| 17 | SD_DAT / IIC_DAT | SD data / IIC data |
| 18 | VDD50 | Power input (2.8–5.0V) |
| 19 | DM / D− | USB D− |
| 20 | DP / D+ | USB D+ |
The module features a built‑in 1W stereo amplifier (ROUT/LOUT) for direct speaker drive. DACR/DACL provide analog audio output for external amplifiers. The BUSY pin indicates playback/connection status.
Application Scenarios
Why Choose WT2605B05
Frequently Asked Questions
What is the WT2605B05?
WT2605B05 is a dual-mode Bluetooth 5.0 audio module with built-in MP3 playback, 1W Class-D amplifier, 16-bit DAC (95dB SNR) and ADC (90dB SNR), AT command UART control, and support for SPI-Flash, TF card, and USB storage.
What Bluetooth profiles WT2605B05 are supported?
WT2605B05 supports A2DP, AVRCP, HFP, and BLE (GATT) profiles for music streaming, remote control, hands-free calling, and data transmission.
What is the Bluetooth name?
The default Bluetooth name is ‘BT_WT2605C’. It can be changed via AT commands.
What storage media are WT2605B05 supported?
WT2605B05 supports SPI-Flash up to 128Mbit, TF card up to 32GB, and USB drive up to 32GB. The chip can switch between Bluetooth mode and audio mode for local playback via AT commands.
What is the audio quality?
WT2605B05 features a 16-bit DAC with 95dB SNR and a 16-bit ADC with 90dB SNR, delivering high-quality audio input and output.
Does it have a built-in amplifier?
Yes. WT2605B05 features a built-in 1W Class-D amplifier that can directly drive an 8Ω speaker, with 32-level volume control.
What control interface does it use?
WT2605B05 uses a standard UART interface with AT command protocol (default 115200 baud). Commands like AT+PLAY, AT+STOP, AT+VOL, AT+CHMODE are supported.
What is the operating voltage range?
The module operates from 2.8V to 5.0V, compatible with both 3.3V and 5V systems.
What is the crystal specification?
The module requires a 24MHz crystal with 12pF load capacitance and ±10PPM frequency tolerance for Bluetooth operation.
What are the typical applications?
Bluetooth speakers, stereo headsets, car audio systems, hands-free car kits, portable navigation devices, smart home devices, and any application requiring wireless audio streaming with AT command control.
Important: A 24MHz crystal (12pF, ±10PPM) is required for Bluetooth operation. The module defaults to Bluetooth mode on power‑up; use AT+CHMODE to switch to audio mode. For external SPI‑Flash, Waytronic‑branded Flash is recommended for guaranteed compatibility. The module’s amplifier outputs (ROUT/LOUT) directly drive 8Ω speakers. When using external amplifiers, connect to DACR/DACL pins. The USB interface supports OTA firmware upgrades and mass storage (when TF card is inserted). Ensure proper antenna layout for optimal Bluetooth range (≤10 meters).
