The **MHO+34TCD-R** is a specific model of a **Crystal Oscillator**, typically manufactured by companies like **Mercury Electronic**. It belongs to the category of Frequency Control products, used to provide a stable clock signal for electronic circuits. Below is a breakdown of its technical specifications and electronic components. --- ### 1. Technical Specifications Table | Parameter | Details | | :--- | :--- | | **Component Type** | Crystal Oscillator (XO) | | **Package Type** | SMD (Surface Mount Device) | | **Package Size** | 3.2mm x 2.5mm (Standard 3225 size) | | **Output Type** | HCMOS / TTL Compatible | | **Supply Voltage (Vcc)** | +3.3V DC (Common for '3' series) | | **Operating Temperature** | -40°C to +85°C (Industrial Grade) | | **RoHS Status** | Compliant (Lead-Free) | --- ### 2. Part Number Breakdown The nomenclature of these parts usually follows a specific coding logic: * **MHO:** Series designation (often indicating a Metal-Hybrid or Miniature Oscillator). * **+:** Usually indicates RoHS compliance. * **3:** Represents the operating voltage (3.3 Volts). * **4:** Represents the frequency stability (often ±50ppm or ±25ppm depending on the specific datasheet version). * **TCD:** Refers to the internal temperature compensation and output characteristics. * **R:** Indicates **Tape & Reel** packaging for automated assembly. --- ### 3. Internal Components and Function The device is an "Active" oscillator, meaning it contains more than just a quartz crystal. Inside the 4-pin ceramic package, you will find: 1. **Quartz Crystal Blank:** A precision-cut piece of quartz that vibrates at a specific frequency via the piezoelectric effect. 2. **Oscillator IC:** A CMOS integrated circuit that provides the necessary amplification and feedback to maintain oscillation. 3. **Bypass Capacitor:** Internal filtering to reduce power supply noise (though external decoupling is still recommended). 4. **Tri-state Function:** Most "TCD" variants include an "Enable/Disable" function on Pin 1, allowing the output to be turned off to save power without powering down the whole system. --- ### 4. Pin Configuration | Pin Number | Function | Description | | :--- | :--- | :--- | | **1** | OE or NC | Output Enable (High = Active, Low = High Impedance) | | **2** | GND | Ground / Case | | **3** | Output | Frequency Signal Output | | **4** | Vdd/Vcc | Power Supply (+3.3V) | --- ### 5. Common Applications * **Networking:** Routers, Switches, and Modems. * **Computing:** Microprocessor clocks and peripheral controllers. * **Industrial:** PLCs and embedded sensors requiring stable timing over a wide temperature range.