## Technical Overview of EB2-4.5TNUH-R The **EB2-4.5TNUH-R** is a specific model within the EB2 series of miniature signal relays manufactured by **KEMET** (formerly TOKIN). These relays are widely used in telecommunications, test equipment, and consumer electronics due to their compact size and high reliability. --- ### 1. Part Number Breakdown Understanding the suffix codes helps identify the specific electronic characteristics of this component: | Code | Meaning | Description | | :--- | :--- | :--- | | **EB2** | Series Name | Miniature Signal Relay (Surface Mount Type) | | **4.5** | Nominal Voltage | 4.5V DC Coil Voltage | | **T** | Latching Type | Double Coil Latching (Remains in state without continuous power) | | **NU** | Standard Type | Standard UL/CSA recognized version | | **H** | High Insulation | Minimum 1000V AC breakdown voltage between open contacts | | **-R** | Packaging | Embossed Tape & Reel packaging | --- ### 2. Key Electrical Specifications This relay is designed for low-power signal switching rather than high-power load switching. | Parameter | Value | | :--- | :--- | | **Contact Form** | 2 Form C (DPDT - Double Pole Double Throw) | | **Coil Voltage** | 4.5 VDC | | **Set/Reset Power** | ~140 mW | | **Max Switching Voltage** | 220V DC / 250V AC | | **Max Switching Current** | 1A | | **Contact Resistance** | 75 mΩ max. (initial) | | **Operating Temperature** | -40°C to +85°C | --- ### 3. Core Features * **Double Coil Latching:** Unlike non-latching relays that require constant current to stay "on," this model uses two coils. One pulse to the "Set" coil flips the switch, and it stays there mechanically until a pulse is sent to the "Reset" coil. This is excellent for battery-powered devices to save energy. * **Compact Footprint:** Designed for high-density SMT (Surface Mount Technology) PCB mounting. * **High Reliability:** Features gold-overlay silver alloy contacts, which prevent oxidation and ensure stable switching for low-level signals. * **Safety Compliance:** Meets Telcordia (1500V) and FCC (1500V) surge requirements. --- ### 4. Typical Applications * **Telecommunications:** PBX systems and modems. * **Measurement Equipment:** Oscilloscopes and signal generators. * **Medical Electronics:** Portable diagnostic tools. * **Audio/Video:** Signal routing and switching.