## Electronic Overview: EB2-12SNU-R Relay The **EB2-12SNU-R** is a high-performance, miniature signal relay manufactured by **KEMET** (formerly NEC/Tokin). It belongs to the EB2 series, which is specifically designed for low power consumption and high reliability in telecommunication and electronic instrumentation. --- ### 1. Key Technical Specifications The following table highlights the primary electrical and physical characteristics of the component: | Feature | Specification | | :--- | :--- | | **Relay Type** | Latching (Single Coil) | | **Contact Form** | 2 Form C (DPDT - Double Pole Double Throw) | | **Nominal Coil Voltage** | 12 VDC | | **Contact Rating** | 30W, 62.5VA (Max 220VDC / 250VAC) | | **Contact Current** | 2A (Maximum) | | **Coil Resistance** | 1440 $\Omega$ (approx.) | | **Power Consumption** | ~100 mW | | **Mounting Type** | Surface Mount (SMT) | | **Termination** | Gull-wing leads | --- ### 2. Detailed Part Number Breakdown Understanding the nomenclature helps identify the specific features of this variant: * **EB2**: Series name (Compact, surface mount). * **12**: Nominal coil voltage (12 Volts). * **S**: Latching type (Single coil). * **NU**: Standard version (Compliant with FCC Part 68). * **-R**: Packaging style (Tape and Reel). --- ### 3. Core Functional Features #### **Latching Mechanism (Single Coil)** Unlike standard non-latching relays that require continuous power to hold the contacts in position, the **EB2-12SNU-R** uses a permanent magnet. A short pulse of 12V electricity moves the contacts, and they remain in that state even after power is removed. This makes it ideal for battery-operated devices. #### **Contact Reliability** The contacts are typically **gold-clad silver alloy**. This construction prevents oxidation and ensures low contact resistance, which is critical for switching low-level signals (dry circuits) without signal degradation. #### **Dielectric and Isolation** * **Breakdown Voltage:** Designed to withstand 1000VAC between open contacts. * **Surge Strength:** Capable of withstanding 1500V (FCC Part 68 compliant), providing protection against lightning and power surges in telecom lines. --- ### 4. Typical Applications * **Telecommunications:** Switching test equipment, PABX, and modems. * **Measurement Equipment:** Oscilloscopes and signal generators. * **Medical Electronics:** Low-power diagnostic portable devices. * **Consumer Electronics:** High-end audio switching where signal integrity is paramount. --- ### 5. Circuit Implementation Note When designing for a **Single Coil Latching** relay, the polarity of the pulse matters: 1. **To Set:** Apply positive voltage to Pin 1 and negative to Pin 10 (or as per datasheet). 2. **To Reset:** Reverse the polarity of the pulse to the same two pins.