The **MH23FDG-R** is a specific electronic component typically identified as a **tactile switch** (or tact switch) manufactured by companies like Mitsumi or similar specialized switch vendors. It is commonly used in consumer electronics for user interface controls. --- ### 1. General Specifications The MH23 series consists of surface-mount (SMT) or through-hole tactile switches known for their high reliability and small footprint. | Feature | Typical Specification | | :--- | :--- | | **Type** | Tactile Switch | | **Circuit Configuration** | SPST (Single Pole Single Throw), Normally Open | | **Mounting Type** | Surface Mount (SMD/SMT) or Snap-in | | **Actuation Force** | 1.0N to 2.5N (varies by sub-model) | | **Travel Distance** | 0.2mm to 0.3mm | | **Life Cycle** | 100,000 to 500,000 cycles | --- ### 2. Key Internal Components The functionality of the MH23FDG-R relies on several precision-engineered layers: 1. **Actuator (Stem):** The physical button pressed by the user. In the "FDG" variant, this is usually a low-profile plastic plunger. 2. **Contact Dome (Snap Plate):** A circular or cross-shaped metal disc (usually stainless steel or phosphor bronze). When pressed, it buckles to provide tactile feedback and completes the electrical circuit. 3. **Base:** A heat-resistant thermoplastic (like LCP) that houses the terminals and protects the internal dome. 4. **Terminals:** Silver or gold-plated copper alloy pins that are soldered to the PCB. 5. **Cover:** A metal frame or film that holds the assembly together and protects against dust. --- ### 3. Part Number Breakdown (Typical) While naming conventions can vary slightly by manufacturer, the suffix codes usually indicate: * **MH23:** The base series (Dimensions/Family). * **F/D/G:** These letters often refer to the height of the stem, the operating force (e.g., 160gf), and the plating material. * **-R:** Generally indicates **Tape & Reel** packaging for automated pick-and-place assembly. --- ### 4. Application Areas Because of its small size and momentary action, you will find this part in: * **Portable Electronics:** Smartphones, tablets, and smartwatches. * **Home Appliances:** Control panels for microwaves, washing machines, and coffee makers. * **Automotive:** Dashboard buttons, steering wheel controls, and key fobs. * **Industrial:** Reset buttons on PCBs and interface controllers. --- ### 5. Schematic Representation The switch is represented in a circuit diagram as a simple open contact: ```text (Terminal 1) ----\ ---- (Terminal 2) \ (Switch) ```