The **QC-R** (Quick Charge - Receiver) generally refers to the electronic sub-system or module responsible for receiving wireless power or high-speed wired power delivery. In the context of drone technology (like the Skydio QC-R) or generic wireless charging, it involves several critical electronic components designed to manage high-current induction and voltage regulation. ### 1. Core Electronic Components The architecture of a QC-R module is divided into power reception, conversion, and communication layers. | Component | Function | Description | | :--- | :--- | :--- | | **Rx Coil (Induction)** | Energy Capture | A copper wire coil that picks up the electromagnetic field from the transmitter (TX). | | **Rectifier Bridge** | AC to DC Conversion | Typically a synchronous rectifier (MOSFET-based) to convert alternating current to direct current with low heat loss. | | **QC Controller IC** | Protocol Logic | The "brain" that communicates with the charger to request specific voltages (e.g., 5V, 9V, 12V). | | **Buck/Boost Converter** | Voltage Regulation | Adjusts the incoming voltage to the exact level required by the battery management system (BMS). | | **Resonant Capacitors** | Tuning | High-precision capacitors used to tune the receiver coil to the specific frequency of the transmitter. | --- ### 2. Functional Blocks of the QC-R #### A. Communication Interface The QC-R must "handshake" with the power source. * **Wired (USB-PD/QC):** Uses the D+ and D- lines (or CC lines for USB-C) to negotiate power profiles. * **Wireless (Qi/Proprietary):** Uses **In-band Modulation**, where the receiver changes its load impedance to send data packets back to the transmitter coil. #### B. Thermal Management High-speed charging generates significant heat. QC-R boards often include: * **NTC Thermistors:** Sensors that monitor component temperature. * **Thermal Vias:** Copper-filled holes in the PCB to dissipate heat to the outer casing. #### C. Protection Circuitry To prevent damage to the device, the QC-R includes: * **OVP (Over Voltage Protection):** Shuts down the circuit if the transmitter sends too much power. * **FOD (Foreign Object Detection):** Detects metal objects between the coils to prevent fires. --- ### 3. Example Block Diagram Logic ```mermaid graph LR A[Rx Coil] --> B[Rectifier] B --> C[Voltage Regulator] C --> D[Battery/Device] E[QC Controller] -- Signal --> A E -- Feedback --> C ``` ---