WT2003HM05 Voice Module
Ultra‑Compact 8‑Pin Voice Module with UART, 1‑Wire & 2‑Wire Control, 900s Built‑in Voice
The WT2003HM05 is an ultra‑compact 8‑pin voice module offering the same powerful functionality as the WT2003HM04 in a much smaller footprint. It supports UART, 1‑wire, and 2‑wire serial control options to suit various system architectures. Powered by a 32‑bit processor up to 120MHz, it features 900 seconds of built‑in voice storage and supports external SPI‑Flash up to 128Mbit. With 32‑level (UART) or 8‑level (1/2‑wire) volume control, a built‑in 0.5W Class‑D amplifier, and USB mass storage emulation, it is ideal for space‑constrained designs.
- 32‑bit processor – 120MHz for smooth playback
- 3 control modes – UART, 1‑wire, 2‑wire (selectable)
- 900s built‑in voice – plus SPI‑Flash expansion
- Ultra‑compact 8‑pin – 10.16×10.16mm footprint
- Built‑in 0.5W amp – direct speaker drive
Function Code Selection
| Function Code | Communication Protocol | Default Output | Storage |
|---|---|---|---|
| A04 | UART | PWM (DAC via command) | Built‑in + SPI‑Flash |
| A05 | 1‑wire (single‑byte) | ||
| A07 | 2‑wire (single‑byte) | ||
| A15 | 1‑wire (double‑byte) | ||
| A17 | 2‑wire (double‑byte) |
The control mode is fixed during programming and must be specified when ordering. Contact Waytronic sales for custom requirements.
HM04 vs HM05 – Which to Choose?
| Feature | WT2003HM04 | WT2003HM05 |
|---|---|---|
| Package | 20‑pin module | 8‑pin module |
| Size | 21.01 × 18.21mm | 10.16 × 10.16mm |
| Pin Pitch | 2.0mm | 2.54mm |
| Control Modes | UART / 1‑wire / 2‑wire | UART / 1‑wire / 2‑wire |
| Built‑in Voice | 900 seconds | 900 seconds |
| SPI‑Flash Support | ✔ Up to 128Mbit | ✔ Up to 128Mbit |
| Built‑in Amplifier | ✔ 0.5W | ✔ 0.5W |
| USB Mass Storage | ✔ | ✔ |
HM05 offers the same features as HM04 in a significantly smaller package – ideal for compact designs.
Key Features
Technical Specifications
| Parameter | Value / Condition |
|---|---|
| Processor | 32‑bit, up to 120MHz |
| Operating Voltage | 2.6V – 5.0V (ripple <5%, peak <5.5V) |
| Built‑in Voice Storage | 900 seconds |
| External SPI‑Flash | Up to 128Mbit (FAT/FAT32) |
| Audio Formats | MP3, WAV (8–320kbps) |
| Audio Output | PWM (0.5W Class‑D) / DAC |
| Volume Levels | UART: 32 (0–31), 1/2‑wire: 8 (E0–E7) |
| Playback Modes | Normal, Single loop, All loop, Random, Combo, Insert |
| Control Interfaces | UART (9600 baud), 1‑wire, 2‑wire |
| Deep Sleep Current | < 3 µA |
| Standby Sleep Current | < 30 µA |
| IO Drive Capability | Up to 64mA |
| Operating Temperature | ‑40°C ~ +85°C |
| Module Size | 10.16 × 10.16mm |
| Pin Pitch | 2.54mm |
| Pins | 8 |
UART Command Highlights
| Command | Function | Description |
|---|---|---|
| A0 | Index Playback | Play by index in Flash |
| A1 | Filename Playback | Play by 4‑byte filename |
| AA | Pause / Resume | Toggle pause |
| AB | Stop | Stop playback |
| AC/AD | Next / Previous | Track navigation |
| AE | Volume | Set 0–31 |
| AF | Playback Mode | Normal / Loop / All‑loop / Random |
| B0 | Combo Playback | Play up to 20 tracks in sequence |
| B1 | Insert Playback | Insert a track during playback |
| B6 | Output Switch | PWM ↔ DAC |
| B8 | Low Power | Deep sleep (00) or standby (01) |
| C0–C3 | Queries | Version, volume, status, file count |
| C9 | Current Track | Get playing address |
1‑Wire & 2‑Wire Command Highlights
| Command | Function | Description |
|---|---|---|
| 00H–DFH | Play Address | Play corresponding voice segment (224 addresses) |
| E0H–E7H | Volume Control | E0 min, E7 max (8 levels) |
| F0 | Auto Sleep | Enter sleep after playback |
| F1 | Exit Auto Sleep | Stay in standby |
| F2 | Loop Playback | Loop current segment |
| F3 | Chain Playback | Play multiple addresses sequentially (max 10 segments) |
| F4 00/01 | Output Switch | DAC (00) / PWM (01) |
| F4 02/03 | Sleep Mode | Deep (02) / Standby (03) |
| FE | Stop | Stop playback |
Pin Functions (8‑Pin Module)
| Pin | Name | Function |
|---|---|---|
| 1 | TX | UART transmit |
| 2 | RX | UART receive |
| 3 | DM | USB D− |
| 4 | DP | USB D+ |
| 5 | GND | Ground |
| 6 | VCC | Power input (2.6–5.0V) |
| 7 | SPK+ | Speaker positive |
| 8 | SPK− | Speaker negative |
The 8-pin design simplifies PCB layout while maintaining full functionality.
Application Scenarios
Why Choose WT2003HM05
Frequently Asked Questions
What control modes does WT2003HM05 support?
WT2003HM05 supports UART, 1-wire serial, and 2-wire serial control modes. The specific mode is fixed during programming and must be selected when ordering using the function code (A04 for UART, A05 for 1-wire single-byte, A07 for 2-wire single-byte, A15 for 1-wire double-byte, A17 for 2-wire double-byte).
How does HM05 differ from HM04?
WT2003HM05 offers the same functionality as HM04 (900s voice, multi-mode control) but in a much smaller 10.16×10.16mm 8-pin package, making it ideal for space-constrained designs.
Does WT2003HM05 have a built-in amplifier?
Yes. WT2003HM05 features a built-in 0.5W Class-D amplifier with PWM output. DAC output is also available with a command switch (B6 for UART or F4 00 for 1-wire/2-wire).
How many volume levels are available?
For UART mode, 32 levels (0–31). For 1-wire and 2-wire modes, 8 levels (E0–E7). Volume settings have power-off memory.
What is the operating voltage range?
The WT2003HM05 module operates from 2.6V to 5.0V, with ripple controlled within 5% and peak voltage below 5.5V.
Can I update audio files via USB?
Yes. Connect the module to a PC via USB, and the Flash storage appears as a removable drive. Copy audio files directly, then disconnect USB before sending serial commands.
What is the module size?
The module measures 10.16mm × 10.16mm with 2.54mm pin spacing, making it one of the most compact voice modules in the WT2003 series.
What audio formats are supported?
It supports MP3 and WAV formats with bitrates from 8kbps to 320kbps.
What is the power consumption in sleep mode?
Deep sleep consumes less than 3µA, while standby sleep consumes less than 30µA. The default is deep sleep mode.
What are the typical applications?
Compact voice prompt systems, portable devices, home appliances, automotive electronics, toys, industrial alarms, and any application requiring multi-mode control in a small footprint.
Important: The control mode is fixed during programming – specify the function code when ordering. For external SPI‑Flash, Waytronic‑branded Flash is recommended for guaranteed compatibility. After copying audio files via USB, disconnect the USB cable before sending serial commands. The BUSY function is not available as a dedicated pin on the 8‑pin package (use UART query commands for status). In deep sleep mode, wake the chip with a 0xFE command and wait 100ms before sending other commands. The default output is PWM – use the appropriate command to switch to DAC.
