The **P9225-R-EVK** is an Evaluation Kit designed by Renesas Electronics to demonstrate and test the **P9225-R**, a highly integrated power receiver (Rx) used in wireless charging applications. It is specifically tailored for low-power applications such as wearables and IoT devices. --- ## 1. Core Component: The P9225-R IC The heart of the evaluation board is the **P9225-R** Integrated Circuit. This chip is a 5W wireless power receiver compliant with the WPC (Wireless Power Consortium) Qi standard. | Feature | Specification | | :--- | :--- | | **Output Power** | Up to 5 Watts | | **Output Voltage** | Adjustable (via I2C or Resistor) | | **Communication** | I2C Interface | | **ADC** | Integrated 12-bit ADC for voltage/current monitoring | | **Protection** | Over-voltage, Over-current, and Thermal shutdown | --- ## 2. Key Electronic Sections of the EVK The board is divided into several functional blocks that allow the IC to operate and interface with other devices: ### A. Resonant Tank (LC Circuit) * **Receiver Coil:** A specific copper coil is attached to the board to capture the magnetic flux from a transmitter. * **Resonant Capacitors:** High-quality, low-ESR ceramic capacitors are used to tune the circuit to the Qi resonant frequency (typically around 110-205 kHz). ### B. Rectification & Power Conditioning * **Synchronous Rectifier:** Inside the P9225-R, an integrated full-bridge synchronous rectifier converts AC from the coil to DC. * **Filtering Capacitors:** Large bulk capacitors (located at the `VOUT` pin) smooth the DC voltage to provide a stable power supply to the load. ### C. Communication & Control * **I2C Pull-up Resistors:** Necessary for interfacing the EVK with a microcontroller or the Renesas USB-to-I2C bridge. * **FOD (Foreign Object Detection) Tuning:** A network of resistors used to calibrate the power loss accounting, ensuring safety if metal objects are placed near the charger. ### D. Interface Connectors * **VOUT / GND Pins:** Test points for connecting the actual load or measuring the output. * **I2C Header:** Used for programming the internal MTP (Multi-Time Programmable) memory and real-time monitoring. --- ## 3. Technical Specifications Table | Component Type | Description | | :--- | :--- | | **Input** | AC Magnetic Induction (Qi Standard) | | **Output Connector** | Headers for VOUT and GND | | **Status Indicators** | On-board LEDs for Power/Status signaling | | **Operating Temp** | -40°C to +85°C | | **Form Factor** | Small, optimized for integration into wearable prototypes | --- ## 4. Programming and Tools To use the P9225-R-EVK effectively, users typically employ the **Renesas Wireless Power GUI**. This software allows you to: 1. Read the battery voltage and charging current. 2. Adjust the output voltage setpoint. 3. Configure the Foreign Object Detection (FOD) thresholds.