## Overview of the EB2-4.5SNUL-R The **EB2-4.5SNUL-R** is a high-performance, miniature signal relay manufactured by **KEMET** (formerly NEC/Tokin). It belongs to the EB2 series, which is widely recognized for its compact size, high reliability, and low power consumption. This specific model is a **single-coil latching relay**, designed for space-constrained PCB applications. --- ### Key Specifications and Parameters | Parameter | Specification | | :--- | :--- | | **Contact Form** | 2 Form C (DPDT - Double Pole Double Throw) | | **Nominal Coil Voltage** | 4.5 VDC | | **Coil Type** | Single Coil Latching | | **Contact Rating** | 30W, 62.5VA (Max 220VDC / 250VAC) | | **Switching Current** | 1A (Maximum) | | **Power Consumption** | Approx. 100 mW | | **Mounting Type** | Surface Mount (SMT) | | **Terminal Shape** | Gull-wing (Standard SMT leads) | --- ### Part Number Breakdown To understand the specific features of this component, we can decode the suffix: * **EB2**: Series name (Compact, 2nd generation signal relays). * **4.5**: Indicates the rated coil voltage (4.5 Volts). * **S**: Represents **Single-coil latching** type. * **NUL**: Indicates UL/CSA recognized safety standards and high breakdown voltage. * **-R**: Indicates the packaging type (**Taping/Reel**) for automated SMT assembly. --- ### Functional Characteristics #### 1. Latching Mechanism Unlike standard non-latching relays that require continuous power to stay engaged, the **Single-coil Latching** mechanism only requires a brief pulse to switch states. Once switched, it remains in that position without further power. To switch it back, the polarity of the pulse must be reversed. #### 2. Contact Reliability The contacts are typically made of **Silver alloy with gold overlay**, ensuring low contact resistance and high reliability even when switching low-level signals (dry circuits). #### 3. Compact Design The EB2 series is known for its low profile, making it ideal for high-density mounting on printed circuit boards. --- ### Typical Applications * **Telecommunications:** PABX systems, modems, and line cards. * **Instrumentation:** Measurement equipment and oscilloscopes. * **Consumer Electronics:** Audio-visual equipment and smart home controllers. * **Medical Equipment:** Portable diagnostic devices requiring low power consumption. ---