The **CSS1375F** is a high-performance, surface-mount Current Sense Resistor manufactured by **Susumu**. It belongs to the CSS series, which is specifically designed for high-power applications requiring precision and stability. --- ## 1. Technical Specifications The CSS1375F is engineered to handle high current loads while maintaining a very low resistance value to minimize power loss. | Parameter | Specification | | :--- | :--- | | **Resistance Range** | 0.5mΩ to 10mΩ | | **Power Rating** | Up to 5W (depending on mounting) | | **Tolerance** | ±1.0% (F) | | **Package Size** | 1375 (Inch) / 3219 (Metric) | | **TCR (Temp. Coefficient)** | ±50ppm/°C or ±150ppm/°C | | **Operating Temp.** | -55°C to +170°C | --- ## 2. Key Electronic Features The internal construction of the CSS1375F focuses on thermal management and signal integrity. * **Metal Foil Construction:** Unlike thick-film resistors, the CSS1375F uses a metal foil resistive element. This provides superior stability and lower noise. * **Low Inductance:** The physical geometry is optimized to have very low parasitic inductance, making it suitable for high-frequency switching power supplies. * **High Heat Dissipation:** The "1375" elongated footprint allows for better heat spread across the PCB traces compared to standard square packages. * **Long-side Terminals:** This part often features terminals on the long sides (wide terminal type), which reduces the internal thermal resistance and improves solder joint reliability. --- ## 3. Application Use Cases Because it can measure high currents with high accuracy, it is commonly found in the following circuits: ### Power Management Used in **DC-DC converters** and **Voltage Regulator Modules (VRMs)** to monitor output current and provide feedback for over-current protection. ### Automotive Systems Ideal for battery management systems (BMS) in electric vehicles and electronic power steering, where reliability under high temperatures is critical. ### Industrial Electronics Found in motor controllers and inverter circuits where precise current sensing is required to manage torque and speed. --- ## 4. Typical Circuit Diagram In a standard sensing application, the CSS1375F is placed in series with the load. The voltage drop ($V = I \times R$) is measured by an amplifier. ```text [Power Source] ----+---- [Load] ----+---- [GND] | | | (CSS1375F) | +--[Resistor]----+ | [Current Sense Amp] ```