The **ALV-621-R** is a specific electronic component primarily identified as a **tactile switch** (or tact switch) manufactured by companies like **Dipty** or **Alpha**. It is a surface-mount device (SMD) used to provide a physical user interface for electronic devices. --- ### 1. Key Technical Specifications Below are the standard technical parameters for the ALV-621-R series: | Parameter | Specification | | :--- | :--- | | **Component Type** | Tactile Switch (Push Button) | | **Mounting Type** | SMD (Surface Mount Device) | | **Dimensions** | 6.2mm x 6.2mm | | **Actuation Force** | 160gf (Grams-force) / 250gf (varies by suffix) | | **Voltage Rating** | 12V DC | | **Current Rating** | 50mA | | **Contact Resistance** | ≤ 100mΩ | | **Life Cycle** | ~100,000 to 500,000 cycles | --- ### 2. Physical Construction The ALV-621-R consists of several internal electronic parts: 1. **Cover/Frame:** Usually made of stainless steel or plastic to protect the internal mechanism. 2. **Actuator (Stem):** The button part you press. In the "621" series, the height of this stem can vary. 3. **Contact Dome:** A precision-engineered metal snap-dome. When pressed, it collapses to complete the circuit and provides the "click" tactile feedback. 4. **Base:** A high-temperature resistant plastic (LCP or Nylon) that holds the terminals. 5. **Terminals:** Silver-plated brass or copper leads that are soldered to the PCB. --- ### 3. Circuit Configuration Most ALV-621-R switches use a **SPST (Single Pole Single Throw)** configuration. ```mermaid graph LR A[Terminal 1] --- B((Switch)) B((Switch)) --- C[Terminal 2] style B fill:#f9f,stroke:#333,stroke-width:2px ``` * **Normally Open (NO):** The circuit is disconnected until the button is pressed. * **Momentary Action:** The switch returns to the "Open" position as soon as the finger is removed. --- ### 4. Common Applications * **Consumer Electronics:** Remote controls, microwave panels, and calculators. * **Industrial:** Reset buttons on PCBs and interface controls. * **Computing:** Mouse buttons or power buttons on laptops. ---