## Technical Analysis: RL3264L4-R005-J The **RL3264L4-R005-J** is a high-precision, low-resistance chip resistor commonly used for current sensing applications. It is manufactured by **Susumu**, a leader in thin-film technology. --- ### 1. Part Number Breakdown Understanding the nomenclature helps identify the physical and electrical characteristics of the component: | Segment | Value | Description | | :--- | :--- | :--- | | **RL** | Series | Low resistance chip resistor series. | | **3264** | Case Size | 3.2mm x 6.4mm (Metric 6432 / Imperial 2512). | | **L4** | Terminal Style | 4-terminal (Kelvin) configuration for high accuracy. | | **R005** | Resistance | 0.005 Ohms (5 mΩ). | | **J** | Tolerance | ±5.0% Resistance Tolerance. | --- ### 2. Key Specifications The following table highlights the core electrical and physical parameters: | Parameter | Value | | :--- | :--- | | **Resistance** | 5 mΩ (0.005 Ω) | | **Power Rating** | 1.0 Watt | | **Tolerance** | ±5% | | **Operating Temp** | -55°C to +125°C | | **TCR** | ±100 ppm/°C (Temperature Coefficient) | | **Technology** | Metal Foil / Thin Film | --- ### 3. Functional Features The RL series is engineered for power management circuits. Here are its primary technical advantages: * **Kelvin (4-Terminal) Structure:** Unlike standard 2-terminal resistors, the L4 designation indicates 4 terminals. This allows the current path and the voltage sensing path to be separated, eliminating the lead resistance from the measurement and ensuring extreme accuracy in current sensing. * **Low Inductance:** The thin-film construction results in very low parasitic inductance, making it suitable for high-frequency switching power supplies. * **Heat Dissipation:** The 2512 (3264) footprint provides a large surface area for efficient thermal management at 1W power loads. --- ### 4. Common Applications Due to its low resistance and high power handling, this part is typically found in: 1. **Battery Management Systems (BMS):** Monitoring charge/discharge cycles. 2. **DC-DC Converters:** Sensing output current for regulation. 3. **Motor Controllers:** Detecting over-current conditions. 4. **Inverters:** High-efficiency power conversion monitoring. --- ### 5. Land Pattern (Reflow) The 4-terminal layout requires a specific PCB pad design to utilize the Kelvin sensing capability effectively: ```text [ Current In ] [ Current Out ] | | [Terminal 1/4]-----------[Terminal 2/3] | | [ Voltage Sense ] [ Voltage Sense ] ```