The part number **OMM02040D3JB3** refers to a high-reliability **Thin Film MELF (Metal Electrode Leadless Face)** resistor, typically manufactured by **Vishay Beyschlag**. These resistors are known for their exceptional stability, reliability, and pulse load capability compared to standard thick film chip resistors. ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Resistor Type** | Thin Film MELF | | **Case Size** | 0204 (Mini-MELF) | | **Resistance Value** | Varies by specific suffix (Standard series base) | | **Tolerance** | Typically ±5% (indicated by 'J') | | **Power Rating** | 0.25 W (at 70°C) | | **Operating Voltage** | 200 V (Maximum) | | **Temperature Coefficient** | ±100 ppm/K (Standard) | | **Operating Temp Range** | -55°C to +155°C | --- ### 2. Physical Construction and "MELF" Advantage The **MELF** (Metal Electrode Leadless Face) design is cylindrical rather than flat. This provides several advantages: * **Thermal Dissipation:** The cylindrical shape offers a larger surface area for cooling. * **Pulse Stability:** The thin film layer is wrapped around a ceramic core, providing superior performance under high-energy pulse conditions. * **Mechanical Strength:** High resistance to board flex and vibration. ### 3. Part Number Breakdown (OMM0204) * **OMM:** Professional High Stability Resistor Series. * **0204:** The DIN size (3.6 mm length, 1.4 mm diameter). * **D:** Suffix often relating to Temperature Coefficient or specific series characteristic. * **3:** Can denote the power rating or a specific internal design code. * **J:** Tolerance code (J = ±5%). * **B3:** Packaging code (typically referring to Blister tape/Reel). --- ### 4. Applications Because of its high reliability, this component is commonly found in: 1. **Automotive Electronics:** Engine control units and safety systems. 2. **Industrial Systems:** Measurement equipment and power supplies. 3. **Telecommunications:** Base stations and infrastructure hardware. 4. **Medical Equipment:** Devices requiring long-term stability and low noise. ---