The **WPT-15W2-R** is a high-performance wireless power transfer (WPT) receiver module designed for Qi-compliant wireless charging. It is typically used in portable electronics, medical devices, and industrial sensors requiring up to 15W of power. ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Output Power** | 15W (Max) | | **Compliance** | Qi WPC v1.2.4 (Extended Power Profile - EPP) | | **Output Voltage** | Typically 5V, 9V, or 12V DC (Configurable) | | **Efficiency** | ~80% - 85% (depending on coil alignment) | | **Operating Frequency** | 110 kHz - 205 kHz | --- ### 2. Core Electronic Components The module consists of several critical stages to convert electromagnetic waves into stable DC power: #### A. The Receiver (Rx) Coil * **Material:** Usually an ultra-thin Litz wire coil with a ferrite backing. * **Function:** Captures the magnetic flux generated by the transmitter (Tx) and converts it into AC current via induction. #### B. Integrated Circuit (IC) Controller The "brain" of the module is usually a dedicated Wireless Power Receiver IC (such as those from **Renesas/IDT** or **Texas Instruments**). It handles: * **Rectification:** Converts the high-frequency AC from the coil into DC. * **Communication:** Uses back-scatter modulation to send "packets" to the transmitter to negotiate power levels and safety status. * **Voltage Regulation:** Ensures the output remains steady at the desired voltage (e.g., 9V). #### C. Resonance Capacitors * **Function:** High-precision C0G/NP0 ceramic capacitors are used to tune the receiver circuit to the specific resonant frequency of the transmitter. This maximizes energy transfer efficiency. #### D. Protection Circuitry * **FOD (Foreign Object Detection):** Detects metal objects (like coins or keys) between the coil and transmitter to prevent overheating. * **OTP/OVP:** Over-Temperature and Over-Voltage protection circuits to prevent damage to the load device. --- ### 3. Application Schematic Logic The general flow of electricity within the WPT-15W2-R follows this path: ```mermaid graph LR A[Rx Coil] --> B[Resonant Capacitors] B --> C[Bridge Rectifier] C --> D[DC-DC Buck/Boost Converter] D --> E[USB/Battery Load] ``` ### 4. Implementation Considerations * **Thermal Management:** At 15W, the module generates heat. It is often paired with a thermal pad or heat sink. * **Alignment:** Peak efficiency is only achieved when the Rx coil is centered over the Tx coil. * **Shielding:** Ferrite sheets are included on the back of the coil to prevent the magnetic field from interfering with the internal electronics of the device being charged.