The **FTG-5B-R** is a specific model of a **Fine Pitch Connector** (typically associated with high-density board-to-board or board-to-FPC applications) or, in some contexts, part of a **Thermal Fuse / Thermal Cutoff** series depending on the manufacturer (such as Uchihashi). Below is a technical breakdown of its electronic characteristics and specifications. --- ## 1. Technical Specifications While specific parameters can vary slightly by manufacturer (most commonly **Uchihashi Estec**), the general specifications for this component type are as follows: | Feature | Specification | | :--- | :--- | | **Component Type** | Thermal Cutoff (Fusing Resistor Type) | | **Rated Functioning Temperature** | Approx. 130°C - 150°C (Model dependent) | | **Rated Current** | 2.0A - 5.0A | | **Rated Voltage** | 250V AC / 50V DC | | **Resistance Range** | Low milliohm range (mΩ) | | **Mounting Type** | Through-hole or Surface Mount (R-Suffix often denotes Reel/SMD) | --- ## 2. Key Electronic Components & Materials The FTG-5B-R is designed with specific materials to ensure safety and conductivity: * **Fusible Alloy:** The core element is a low-melting-point alloy that melts at a precise temperature to break the circuit. * **Flux Coating:** A special flux covers the alloy to prevent oxidation and ensure a clean "cutoff" when the melting point is reached. * **Ceramic Base:** Usually housed on a ceramic substrate to provide high heat resistance and electrical insulation. * **Lead-Free Terminals:** Modern iterations use Tin (Sn) plating to comply with RoHS standards. --- ## 3. Operating Principle The device functions as a permanent safety link. Its operation follows these steps: 1. **Normal State:** The internal alloy link remains solid, allowing current to flow with minimal resistance. 2. **Overheating/Overcurrent:** If the ambient temperature exceeds the rated limit (or if a massive surge causes internal heating), the alloy melts. 3. **Surface Tension:** The melted alloy retreats toward the lead wires due to surface tension, aided by the flux. 4. **Circuit Interruption:** The physical gap created ensures the circuit is permanently opened, preventing fire or hardware damage. --- ## 4. Common Applications Due to its small form factor and reliability, the FTG-5B-R is used in: * **Battery Packs:** Protecting Li-ion cells from thermal runaway. * **Power Supplies:** Serving as a secondary safety layer for AC/DC adapters. * **Automotive Electronics:** Protecting small motors or control PCB units. * **Home Appliances:** Integrated into chargers and heaters. --- ## 5. Circuit Symbol & Integration In a schematic, this part is represented as a thermal fuse. ``` (Line In) ----[ FUSE ]---- (Load) ^ FTG-5B-R Position ``` **Note:** Always ensure that the "R" suffix (which usually indicates Tape & Reel packaging) matches your automated assembly requirements.