WTK6900HC3-32N Voice Recognition Chip
240MHz AI Core · 5m Far‑Field · 4MB Flash · Bluetooth 5.1 · QFN32
The WTK6900HC3-32N is the flagship of the HC series, housed in a compact QFN32 package with the largest 4MB SPI Flash capacity. It features a 240MHz core, 5‑meter far‑field recognition, and Bluetooth 5.1 for wireless connectivity. With an extensive set of I/O pins, SPI, and high‑performance audio (95dB SNR DAC), this chip is ideal for advanced smart home hubs, industrial controllers, and automotive infotainment systems.
- 240MHz CPU with FPU
- 5m far‑field reliable recognition
- 4MB SPI Flash (largest in series)
- Bluetooth 5.1 with full profiles
- Rich I/O – UART, SPI, PWM, GPIO
- 95dB SNR DAC & 90dB SNR ADC
Key Features
Technical Specifications
| Parameter | Value / Condition |
|---|---|
| CPU Frequency | 240 MHz (with FPU) |
| Flash Memory | 4 MB (SPI) |
| DAC | Two 16‑bit, SNR ≥ 95dB |
| ADC | Single 16‑bit, SNR ≥ 90dB |
| Audio Formats | MP3, WAV |
| Bluetooth | V5.1+BR+EDR+BLE |
| Supply Voltage | 2.8V – 5.2V |
| IO Level | 3.3V TTL |
| Interfaces | UART, SPI, USB, PWM, GPIO |
| Operating Temperature | –40°C ~ +85°C |
| Package | QFN32 (5×5 mm) |
Pin Description – QFN32
| Pin | Name | Function |
|---|---|---|
| 1 | VMID | Reference (1µF cap to GND) |
| 2 | DACL | DAC left output |
| 3 | DACR | DAC right output |
| 4 | NC | Leave floating |
| 5 | PA4 | I/O |
| 6 | PA3 | I/O |
| 7 | PA2 | I/O |
| 8 | PA1 | I/O |
| 9 | PWM | PWM channel 1 |
| 10 | VDD | Power input |
| 11 | VREG | Regulator (1µF cap) |
| 12 | PWM | PWM channel 2 |
| 13 | PA5 | I/O |
| 14 | PA6 | I/O |
| 15 | PA7 | I/O |
| 16 | VCM | Reference (0.1µF cap to GND) |
| 17 | XIN | 24MHz crystal input |
| 18 | XOUT | 24MHz crystal output |
| 19 | SPI_DO | SPI data out |
| 20 | SPI_DLK | SPI clock |
| 21 | SPI_DI | SPI data in |
| 22 | SPI_CS | SPI chip select |
| 23 | SDA | Programming data (I2C) |
| 24 | SCL | Programming clock (I2C) |
| 25 | UART_RX | UART receive |
| 26 | UART_TX | UART transmit |
| 27 | PB2/BUSY | I/O or busy |
| 28 | PB1 | I/O |
| 29 | VDDDAC | DAC power |
| 30 | MIC | Microphone input |
| 31 | VDDIO | IO power (3.3V) |
| 32 | — | (not listed in excerpt) |
Command Output Examples
| Command | UART Output (Hex) |
|---|---|
| Wake‑up: “小蜂管家” | 7E 06 FF 06 01 01 0D EF |
| “打开灯光” | 7E 06 FF 06 01 02 0E EF |
| “关闭灯光” | 7E 06 FF 06 01 03 0F EF |
| “调亮灯光” | 7E 06 FF 06 01 04 10 EF |
| “调暗灯光” | 7E 06 FF 06 01 05 11 EF |
| “音量增大” | 7E 06 FF 06 01 09 15 EF |
| “音量减小” | 7E 06 FF 06 01 0A 16 EF |
Applications
Why Choose WTK6900HC3-32N
FAQs
What is the advantage of WTK6900HC3-32N?
WTK6900HC3-32N has the largest Flash (4MB) and the most I/O in a compact QFN32 package.
Does WTK6900HC3-32N support SPI and PWM?
Yes, WTK6900HC3-32N has dedicated SPI and two PWM channels.
What is the recognition range?
Up to 5 meters.
Can I use it without Bluetooth?
Yes, Bluetooth is optional – you can use it purely for voice recognition.
Note: QFN32 requires careful PCB layout. Refer to the datasheet for recommended land pattern and decoupling. UART is 3.3V TTL. Custom voice models can be created via the Waytronic online platform.
