## Overview of JFR2-4J3-R The **JFR2-4J3-R** is a specific electronic component belonging to the **Tactile Switch** or **Pushbutton Switch** category, commonly manufactured by specialized switch producers. These components are designed for PCB (Printed Circuit Board) mounting to provide human-machine interface (HMI) input. --- ### 1. Technical Specifications Below are the typical electrical and mechanical parameters for this class of component: | Parameter | Specification | | :--- | :--- | | **Component Type** | Tactile Switch | | **Circuit Configuration** | SPST (Single Pole Single Throw) | | **Mounting Type** | Surface Mount (SMD) / Through-Hole | | **Actuation Force** | Typically 1.6N to 2.5N | | **Contact Rating** | 50mA @ 12VDC | | **Operating Temperature** | -25°C to +70°C | | **Travel** | 0.25mm ± 0.1mm | --- ### 2. Key Internal Components The JFR2 series utilizes several precise parts to function: 1. **Actuator (Button):** The top part that the user presses. Usually made of high-temperature thermoplastic (e.g., LCP or Nylon). 2. **Contact Dome:** A metallic "snap" dome (often stainless steel or phosphor bronze) that provides the tactile feedback and completes the circuit. 3. **Base (Housing):** The frame that holds the contacts and protects the internal mechanism. 4. **Terminals:** Lead-frame pins (often silver-plated) that connect the switch to the circuit board traces. --- ### 3. Pin Configuration & Logic As a standard SPST tactile switch, the internal logic is "Normally Open" (NO). ```text (1) ------- (2) | | [ O ] <-- Contact Bridge (Press to Close) | | (3) ------- (4) ``` * **Pins 1 & 2** are internally connected. * **Pins 3 & 4** are internally connected. * Pressing the button bridges the gap between the 1-2 pair and the 3-4 pair. --- ### 4. Common Applications * **Consumer Electronics:** Handheld devices, remote controls, and white goods. * **Industrial:** Control panels and reset buttons. * **Computing:** Peripheral devices and power buttons. ---