## ADAU7002ACBZ-R7 Technical Overview The **ADAU7002ACBZ-R7** is a specialized, low-power stereo PDM-to-I2S/TDM converter manufactured by **Analog Devices**. Its primary function is to act as an interface bridge between digital MEMS microphones (which output PDM) and digital audio processors or SoCs (which typically require I2S or TDM signals). --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Function** | PDM to I2S/TDM Conversion | | **Input Channels** | 2 Channels (Stereo PDM) | | **Output Formats** | I2S, Left-Justified, TDM (up to 8 channels) | | **Supply Voltage** | 1.62V to 3.63V | | **Sample Rates** | 4 kHz to 96 kHz | | **Package** | 8-ball WLCSP (1.26 mm × 0.81 mm) | | **Power Consumption** | ~0.65 mW (at 48 kHz/1.8V) | --- ### 2. Core Functional Components The device is relatively simple but highly efficient, consisting of several critical stages: 1. **PDM Interface**: It receives one or two Pulse Density Modulation (PDM) streams. It uses the falling and rising edges of the clock to capture stereo data. 2. **Decimation Filter**: This is the "brain" of the chip. It converts the high-over-sampled 1-bit PDM signal into a high-resolution multi-bit PCM signal (Pulse Code Modulation). 3. **High-Pass Filter (HPF)**: It includes an internal filter to remove DC offsets from the microphone signal. 4. **Serial Port (I2S/TDM)**: The output stage formats the PCM data into standard I2S or TDM streams for the host processor. --- ### 3. Application Use Cases Because of its extremely small footprint (WLCSP) and low power draw, it is commonly found in: * **Mobile Handsets**: Connecting digital mics to baseband processors. * **Wearables**: Smartwatches and fitness trackers. * **IoT Devices**: Voice-controlled smart home appliances. * **Computers**: Integrated microphone arrays in laptops. --- ### 4. Advantages of Using ADAU7002 * **No Configuration Needed**: The device is "hard-wired" for its function and does not require an I2C or SPI control interface to set up registers, simplifying software development. * **Space Saving**: The 8-ball Wafer Level Chip Scale Package (WLCSP) is roughly the size of a grain of sand, making it ideal for dense PCB designs. * **High Audio Quality**: It maintains a high Signal-to-Noise Ratio (SNR) during the conversion process, ensuring that the quality of high-end MEMS microphones is not degraded. ---