The **FSM8JSMLSTR** is a specific part number for a surface-mount, tactile electronic switch manufactured by **TE Connectivity (ALCOSWITCH)**. It is widely used in consumer electronics, industrial controls, and PC peripherals. --- ### 1. Technical Specifications The following table highlights the core electrical and mechanical characteristics of the FSM8JSMLSTR: | Parameter | Specification | | :--- | :--- | | **Switch Type** | Tactile (Momentary) | | **Actuator Style** | Round Button (Top Actuated) | | **Mounting Type** | Surface Mount (SMT) / Gull Wing | | **Operating Force** | 160 gf (grams-force) | | **Contact Rating** | 50 mA @ 12 VDC | | **Contact Material** | Silver Plated | | **Body Dimensions** | 6.00mm x 6.00mm | | **Actuator Height** | 9.50mm | | **Life Cycle** | 100,000 Cycles | --- ### 2. Physical Design and Packaging * **Dimensions:** It features a standard 6x6mm footprint, which is an industry standard for tactile switches, making it easily replaceable or compatible with many PCB layouts. * **Height:** The "8" in the series often refers to the specific height profile. With a 9.5mm actuator height, it is tall enough to protrude through a device casing or faceplate. * **Packaging:** The "TR" suffix indicates **Tape & Reel** packaging, designed for automated "pick and place" assembly lines. --- ### 3. Pinout and Circuitry The FSM8JSMLSTR is a **SPST-NO** (Single Pole Single Throw - Normally Open) switch. ```text (1) --- [ ] --- (2) | (3) --- [ ] --- (4) ``` * Internal Connection: Pins 1 & 2 are internally connected, and Pins 3 & 4 are internally connected. * Function: When the button is pressed, it completes the circuit between the 1-2 pair and the 3-4 pair. --- ### 4. Typical Applications Due to its tactile feedback (the "click" sensation), this component is used in: * **Reset Buttons:** On routers, modems, or microcontrollers (like Arduino/ESP32). * **User Interfaces:** Volume buttons, menu navigation, or power toggles. * **Industrial:** Control panels where a physical confirmation of a button press is required.