The **RL3720WT-R010-F** is a high-precision, low-resistance chip resistor manufactured by **Susumu**. It belongs to the RL series, which is specifically designed for current sensing applications due to its "long-side terminal" construction. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Resistance Value** | 10 mΩ (0.010 Ohms) | | **Tolerance** | ±1% (F) | | **Power Rating** | 1.0 Watt | | **Package Size** | 1508 (3720 Metric) | | **Temperature Coefficient (TCR)** | 0 to +350 ppm/°C | | **Operating Temperature** | -55°C to +125°C | | **Technology** | Metal Foil / Thin Film | --- ### 2. Part Number Breakdown Understanding the nomenclature helps identify the physical characteristics: * **RL**: Series Name (Power metal foil chip resistors). * **3720**: Physical Case Size (3.7mm x 2.0mm). * **WT**: Long-side terminal type (Wide terminal). * **R010**: Resistance value (R denotes decimal point; 010 = 0.010Ω). * **F**: Resistance Tolerance (±1.0%). --- ### 3. Distinctive Features #### Long-Side Terminals (Wide Terminal) Unlike standard resistors where terminals are on the short ends, the **WT** designation indicates the terminals are on the long sides. * **Better Heat Dissipation:** The larger terminal surface area allows heat to transfer more efficiently to the PCB. * **Reduced Parasitic Inductance:** Shortens the current path, making it ideal for high-frequency switching applications. * **Solder Joint Integrity:** Offers higher mechanical strength against thermal expansion and contraction. #### Low Resistance (Shunt) With a resistance of only **10 mΩ**, this part acts as a "Shunt Resistor." It is used to measure current by monitoring the small voltage drop across it ($V = I \times R$). --- ### 4. Typical Applications * **Power Management:** DC-DC converters and voltage regulators. * **Battery Monitoring:** Sensing charge/discharge cycles in mobile devices or automotive systems. * **Motor Control:** Detecting overcurrent conditions in industrial drives. * **Audio Equipment:** High-fidelity current sensing in amplifiers. ---