The **FTS-4B-R** refers to a specific series of **Four-Terminal (Kelvin) Kelvin Sockets/Contactors**, typically manufactured by companies like **Ironwood Electronics** or **Loranger**. These parts are precision-engineered components used in the semiconductor testing industry. Below is a detailed breakdown of the electronic and mechanical parts of the FTS-4B-R series. --- ### 1. Core Function and Design The "4B" in the part number usually signifies a **4-point (Kelvin) connection**. This is critical for measuring low resistances accurately by separating the current-carrying wires from the voltage-sensing wires, eliminating the effect of lead and contact resistance. ### 2. Key Electronic & Physical Components | Component | Description | Material/Specification | | :--- | :--- | :--- | | **Contact Pins** | High-performance spring probes or pogo pins. | Typically Gold-plated Beryllium Copper (BeCu). | | **Insulator Body** | The housing that holds the pins in alignment. | High-temperature plastics (e.g., Torlon, Ultem, or PEEK). | | **Contact Interface** | The point where the DUT (Device Under Test) touches the socket. | Designed for low inductance and low contact resistance. | | **Terminals** | The interface to the PCB or Test Equipment. | Solder tail or compression mount. | --- ### 3. Technical Specifications The electronic performance of the FTS-4B-R series is defined by its ability to maintain signal integrity during high-speed or high-power testing. * **Current Rating:** Usually ranges from **0.5A to 3A** per pin depending on the specific pin diameter. * **Contact Resistance:** Typically **<50 mOhms**. * **Operating Temperature:** Generally rated from **-55°C to +155°C** (varies by material). * **Life Cycle:** Rated for **500,000 to 1,000,000 actuations**. ### 4. Application Use Cases * **Burn-in Testing:** Stressing chips at high temperatures to identify early failures. * **Characterization:** Measuring the precise electrical traits of a new integrated circuit (IC). * **Production Testing:** Final QC check before chips are packaged and shipped. --- ### 5. Part Number Breakdown (General Template) While specific manufacturers vary, the nomenclature usually follows this logic: ```text FTS - 4B - R | | | | | └── "R" often denotes RoHS compliance or a specific Revision. | └─────── 4-Beam or 4-Terminal (Kelvin) configuration. └───────────── Force/Test Socket series. ```