The **XR2-5V1-R** is a specific model of a **Miniature Signal Relay**, commonly manufactured by brands like **Coto Technology**. It is designed for high-reliability switching in telecommunications, instrumentation, and medical equipment. --- ## 1. Core Technical Specifications The following table highlights the primary electrical and physical characteristics of the XR2-5V1-R: | Feature | Specification | | :--- | :--- | | **Relay Type** | Reed Relay / Signal Relay | | **Coil Voltage** | 5 VDC | | **Contact Form** | SPST-NO (1 Form A) | | **Contact Rating (Switching)** | 0.5 Amps | | **Max Switching Voltage** | 200 VDC | | **Coil Resistance** | ~500 Ohms (standard for 5V) | | **Mounting Type** | Surface Mount (SMD) | | **RoHS Status** | Compliant (indicated by the "-R" suffix) | --- ## 2. Key Components and Design The XR2 series is built with a focus on high-frequency performance and miniaturization. ### A. Reed Switch Technology Inside the device is a hermetically sealed reed switch. Because the contacts are sealed in glass with an inert gas, they are protected against oxidation and corrosion, ensuring a long mechanical life (often exceeding $10^9$ operations). ### B. The Coil (5V) The "5V" in the part number indicates the nominal operating voltage. It is designed to be driven directly by TTL or CMOS logic levels, making it ideal for interfacing with microcontrollers like Arduino or ESP32 without needing high-power driver circuits. ### C. Magnetic Shielding Many XR2 models include internal magnetic shielding. This prevents magnetic interference between multiple relays when they are mounted close together on a high-density PCB. --- ## 3. Applications Due to its small footprint and high-speed switching capabilities, the XR2-5V1-R is typically found in: 1. **Automated Test Equipment (ATE):** Used for routing low-level signals to measurement instruments. 2. **Telecommunications:** Handling signal switching in modems or line cards. 3. **Security Systems:** High-reliability sensors and alarm loops. 4. **Medical Instrumentation:** Where isolation and low leakage currents are critical. --- ## 4. Part Number Breakdown * **XR2:** Series identifier (typically Surface Mount Reed Relay). * **5V:** 5 Volt nominal coil voltage. * **1:** Configuration code (usually 1 Form A / Normally Open). * **-R:** RoHS compliant (Lead-free).