The **RTS-123.3-R** is a high-performance, surface-mount (SMD) isolated DC/DC converter manufactured by **RECOM Power**. It belongs to the **RTS series**, which is designed for board-level power distribution where space is limited and isolation is required. ### 1. Technical Specifications The part number follows a specific nomenclature that defines its electronic characteristics: | Parameter | Specification | | :--- | :--- | | **Input Voltage** | 12V DC (Nominal) | | **Output Voltage** | 3.3V DC | | **Power Rating** | 1 Watt | | **Isolation Voltage** | 1kV DC (standard) | | **Efficiency** | 70% to 75% (typical) | | **Mounting Type** | SMD (Surface Mount Device) | | **Packaging** | Tape & Reel (indicated by the "-R" suffix) | --- ### 2. Key Electronic Components & Features The internal architecture of the RTS-123.3-R consists of several critical stages: * **Switching Controller:** An internal oscillator that converts the DC input into a high-frequency AC signal. * **Isolation Transformer:** Small-scale magnetic core that provides the 1kV galvanic isolation between the input and output circuits, preventing noise and protecting sensitive components. * **Rectification & Filtering:** High-speed diodes and internal capacitors that convert the AC back to a stable 3.3V DC output. * **Short Circuit Protection:** The unit typically includes "Hiccup mode" or limited short-circuit protection to prevent permanent damage during a fault. --- ### 3. Pin Configuration (SMD) The device usually utilizes a standard land pattern for SMD DC/DC converters. | Pin Number | Function | Description | | :--- | :--- | :--- | | 1 | **-Vin** | Input Ground | | 2 | **+Vin** | Positive Input (12V) | | 5 | **-Vout** | Output Ground | | 8 | **+Vout** | Positive Output (3.3V) | | Others | **NC** | No internal connection | --- ### 4. Typical Applications * **Industrial Controls:** Providing isolated power to logic gates or sensors. * **Data Acquisition:** Eliminating ground loops in sensitive measurement circuits. * **Communication Ports:** Powering isolated RS-485 or CAN bus transceivers. * **Mixed Signal Boards:** Separating digital noise from analog power rails. --- ### 5. Implementation Example To ensure the best performance and EMC compliance, the following external components are often recommended: ```c // Recommended Input Filter (EMI Suppression) L1: 10µH Inductor C1: 4.7µF Electrolytic Capacitor // Output Filter (Ripple Reduction) C2: 10µF Ceramic Capacitor (Low ESR) ```