The term **8-SM-R** typically refers to a specific package sizing or series designation used in electronic components, most commonly associated with **Surface Mount Technology (SMT)** devices like oscillators, crystals, or LED displays. Below is a breakdown of the technical aspects, specifications, and common applications for parts carrying the "8-SM-R" designation. --- ### 1. Technical Specifications Overview In the context of frequency control components (like Quartz Crystals or Oscillators), the "8-SM-R" often denotes a specific footprint and packaging style. | Feature | Description | | :--- | :--- | | **Package Type** | Surface Mount Device (SMD) | | **Number of Pins/Pads** | Usually 2, 4, or 8 (depending on the specific component type) | | **Material** | Ceramic base with a metal seam-sealed lid | | **Mounting Style** | Reflow soldering compatible | | **Standard Size** | Often corresponds to 7.0 x 5.0 mm or 5.0 x 3.2 mm footprints | ### 2. Common Component Types Parts labeled with this nomenclature are generally found in the following categories: #### A. Crystal Units (XTAL) These are passive components used to create an electrical signal with a precise frequency. * **Resonance Mode:** Fundamental or 3rd Overtone. * **Frequency Range:** Typically 8MHz to 150MHz. * **Stability:** High thermal stability, often used in clocking circuits. #### B. Seven-Segment Displays Some manufacturers use "8-SM-R" to describe an 8-digit or 0.8-inch Surface Mount Red (R) LED display. * **Color:** Red (indicated by the 'R'). * **Configuration:** Common Anode or Common Cathode. #### C. Integrated Circuits (SOIC-8) In some legacy catalogs, "8-SM" refers to an **8-pin Small Outline** package. * **Pitch:** 1.27mm. * **Application:** Op-amps, EEPROMs, or voltage regulators. --- ### 3. Key Advantages of the SM-R Series 1. **Miniaturization:** Designed for high-density PCB layouts where space is at a premium. 2. **Automated Assembly:** The flat top surface is designed for high-speed "Pick and Place" machines. 3. **Environmental Resistance:** Most "R" designated parts (especially crystals) are RoHS compliant and feature hermetic sealing to protect against moisture and oxidation. --- ### 4. Identification Guide When sourcing or replacing an 8-SM-R part, check the following: * **The Prefix:** (e.g., *ABS08* or *ECS*) tells you the manufacturer and specific technology. * **Frequency/Voltage:** Look for markings on the top of the casing (e.g., `24.000` for 24MHz). * **The "R" Suffix:** Usually stands for **RoHS Compliant**, **Red** (for LEDs), or **Tape & Reel** (for packaging). ---