The **P9025AC-RNBGI** is a highly integrated, single-chip wireless power receiver developed by Renesas (formerly Integrated Device Technology - IDT). It is designed to meet the **WPC (Wireless Power Consortium) Qi 1.1.2** standard. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Standard** | Qi-compliant (Version 1.1.2) | | **Input Power** | AC input from induction coil | | **Output Power** | Up to 5W | | **Output Voltage** | Integrated 5V High-Efficiency LDO | | **Efficiency** | > 80% (System-level peak) | | **Package** | VFQFPN-32 (5.0 x 5.0 mm) | | **Communication** | Integrated back-channel modulation (ASK) | --- ### 2. Functional Blocks The device integrates several critical electronic components into a single silicon die to minimize PCB footprint: * **Synchronous Full-Bridge Rectifier:** Converts the AC voltage induced in the receiver coil into a stable DC voltage with minimal heat dissipation. * **Integrated LDO (Low Dropout Regulator):** Provides a regulated 5V output to the load (e.g., a battery charging circuit). * **Microcontroller (MCU):** An embedded 8-bit core handles the Qi protocol handshake, power control, and error reporting. * **FOD (Foreign Object Detection):** Monitors power loss between the transmitter and receiver to prevent overheating of metal objects placed in the magnetic field. * **I2C Interface:** Allows for communication with a host processor to monitor status, voltage, and current. --- ### 3. Application Circuit Components While the P9025AC is highly integrated, it requires several external passive components to function: 1. **Resonant Capacitors ($C_1, C_2$):** Critical for tuning the receiver coil to the 100-205 kHz frequency range. 2. **Receiver Coil:** A specific copper wire inductor used to capture the magnetic flux from the transmitter. 3. **Bootstrap Capacitors:** Required for the internal high-side MOSFET drivers of the rectifier. 4. **Commutation Capacitors:** Used to modulate the load for back-channel communication (sending data packets like "End of Power" or "Signal Strength" back to the charging pad). --- ### 4. Pin Configuration Highlights | Pin Name | Function | | :--- | :--- | | **AC1 / AC2** | Input pins connected to the resonant tank (coil). | | **RECT** | Rectified DC voltage output; used for decoupling. | | **OUT** | Regulated 5V output to the system. | | **SCL / SDA** | I2C clock and data lines for configuration and telemetry. | | **EN** | Enable pin to turn the receiver on or off. | --- ### 5. Common Use Cases * Smartphones and mobile accessories. * Wearable electronics (smartwatches, fitness trackers). * Handheld medical devices. * Portable industrial equipment.