The **G3T18AH-R** is a high-quality subminiature toggle switch manufactured by **NKK Switches**. It belongs to the G3T series, which is specifically designed for surface-mount (SMD) applications and is known for its reliability in low-logic-level circuits. --- ### ## Technical Specifications The following table highlights the core electrical and mechanical parameters of the G3T18AH-R: | Parameter | Specification | | :--- | :--- | | **Circuit** | SPDT (Single Pole Double Throw) | | **Switch Function** | (ON) - OFF - (ON) *[Note: ( ) indicates momentary]* | | **Current Rating** | 0.4VA Max @ 28V AC/DC Max | | **Mounting Type** | Surface Mount (Right Angle) | | **Actuator Type** | Standard Lever (Toggle) | | **Terminal Type** | Gull Wing (SMD) | | **Mechanical Life** | 50,000 Cycles | | **Electrical Life** | 50,000 Cycles | --- ### ### Key Electronic Components & Materials 1. **Contact Mechanism:** * The switch utilizes **Gold-plated contacts**. Gold is used because it provides high reliability in low-voltage (logic level) applications by preventing oxidation and ensuring stable conductivity. 2. **Housing/Case:** * Constructed from **Polyphenylene Sulfide (PPS)**. This high-performance plastic is used because it can withstand the high temperatures of infrared (IR) or vapor phase reflow soldering. 3. **Sealing:** * The device is **process sealed**. It features an internal O-ring and a sealed base, allowing it to undergo automated cleaning/washing after soldering without contaminating the contacts. --- ### ### Application and Usage Because the G3T18AH-R is rated for **0.4VA (Volt-Amps)**, it is strictly for logic-level signals and not for power switching. * **Logic Switching:** Ideal for interfacing with Microcontrollers (MCUs) or FPGAs. * **Momentary Action:** Since it is an `(ON) - OFF - (ON)` configuration, the toggle springs back to the center (OFF) position when released. This makes it perfect for "Up/Down" or "Increase/Decrease" user inputs. * **Space Constraint:** The right-angle SMD design allows it to be mounted on the edge of a PCB to save vertical space. --- ### ### Typical Circuit Representation In a standard digital circuit, the switch is usually connected with pull-up resistors: ```c // Logic Flow Example [VCC 3.3V] --- [Resistor] --- [Switch Terminal 1] --- [GPIO Input] [Switch Center Pin] --- [GND] ```