The **RG2-105S-R15** is a high-precision, thin-film chip resistor manufactured by **Susumu**. It belongs to the RG series, which is industry-renowned for its reliability, low noise, and extreme stability under harsh environmental conditions. --- ### 1. Key Technical Specifications The alphanumeric code "RG2-105S-R15" defines the component's physical and electrical characteristics: | Parameter | Value | Description | | :--- | :--- | :--- | | **Resistance** | 0.15 $\Omega$ | Very low resistance value (R15). | | **Tolerance** | ±0.5% (D) or ±0.1% (B) | High precision (S suffix denotes specific series grouping). | | **Power Rating** | 0.25W (1/4 Watt) | Power dissipation capability for the 0805 size. | | **Temperature Coefficient (TCR)** | ±25 ppm/°C | Minimal resistance drift with temperature changes. | | **Package Size** | 2012 (Metric) / 0805 (Inch) | Standard surface mount (SMT) footprint. | | **Operating Temperature** | -55°C to +155°C | Wide industrial/automotive range. | --- ### 2. Electronic Construction The RG series uses a unique **Metal Glaze / Inorganic Thin Film** technology that differentiates it from standard thick-film resistors: * **Thin Film Deposition:** The resistive element is sputtered onto a high-purity alumina substrate, allowing for a much more uniform molecular structure than thick-film "pastes." * **Nitride Thin Film:** Susumu specifically uses a sulfur-resistant and moisture-resistant inorganic coating, making these parts nearly immune to "silver migration" and environmental aging. * **Lead-Free Terminations:** The terminals are usually Matte Tin (Sn) over a Nickel (Ni) barrier, ensuring compliance with RoHS standards. --- ### 3. Applications and Usage Due to its low resistance (0.15 $\Omega$) and high stability, this specific part is typically used in the following circuits: 1. **Current Sensing:** Because of the low ohmic value, it is ideal for measuring current flow in power management circuits with minimal voltage drop. 2. **Precision Measurement:** Used in medical instrumentation or high-end audio equipment where signal integrity and low thermal noise are critical. 3. **Automotive Electronics:** Frequently found in ECUs and sensors where long-term reliability under thermal cycling is required. --- ### 4. Comparison: Thin Film vs. Thick Film | Feature | RG2-105S-R15 (Thin Film) | Standard Resistor (Thick Film) | | :--- | :--- | :--- | | **Noise** | Extremely Low | Moderate | | **Stability (Life)** | ±0.1% drift | >1.0% drift | | **Reliability** | AEC-Q200 Compliant | Standard | | **Cost** | Higher | Lower |