The **MHO+27TCD-R** is a specific model of a **Quartz Crystal Oscillator**, typically manufactured by companies like **Mercury Electronic**. These components are critical for providing a stable clock signal in digital circuits. --- ### 1. Part Number Breakdown To understand the electronic capabilities of this part, we can decode the typical nomenclature used for this series: | Segment | Meaning | Specification Details | | :--- | :--- | :--- | | **MHO** | Series Name | Metal Hybrid Oscillator (usually HCMOS/TTL compatible). | | **+** | RoHS Compliant | Indicates the part is lead-free. | | **27** | Voltage Code | Typically represents **2.7V or 3.3V** operation. | | **TCD** | Stability/Temp | Refers to Temperature Coefficient and Operating Range. | | **-R** | Packaging | Indicates **Tape & Reel** packaging for automated assembly. | --- ### 2. Key Technical Specifications Based on the standard parameters for the MHO series, the electronic characteristics are as follows: * **Frequency Range:** Usually available from 1.0 MHz to 150 MHz (The specific frequency is typically printed on the physical casing). * **Output Logic:** **HCMOS/TTL**. This means it can drive standard digital logic gates directly. * **Supply Voltage ($V_{DD}$):** Optimized for low power, typically **3.3V** (range 2.7V to 3.6V). * **Frequency Stability:** Often ±25ppm to ±100ppm depending on the specific "TCD" grade. * **Operating Temperature:** Generally covers the industrial range (**-40°C to +85°C**). * **Package Type:** Through-hole (4-pin DIP) or SMD equivalent, often housed in a metal "can" to reduce Electromagnetic Interference (EMI). --- ### 3. Pin Configuration For a standard 4-pin crystal oscillator in this series, the pinout is generally: | Pin Number | Function | Description | | :--- | :--- | :--- | | **1** | NC or Tri-state | No connection or Output Enable (OE). | | **2** | GND | Ground connection. | | **3** | Output | The generated clock signal (Square wave). | | **4** | $V_{DD}$ | Positive Power Supply. | --- ### 4. Common Applications Because of its stability and standard logic output, the MHO+27TCD-R is used in: 1. **Microcontrollers:** Providing the master clock for CPUs. 2. **Networking:** Timing for Ethernet or Wi-Fi modules. 3. **Industrial Controls:** Synchronization in automation hardware. 4. **Embedded Systems:** General-purpose timing for PCB designs. --- ### 5. Implementation Example (Schematic Logic) When integrating this into a circuit, a decoupling capacitor (typically 0.1µF) is required between $V_{DD}$ and GND to filter noise. ```cpp // Logic Representation of Clock Usage void setup() { // The MHO+27TCD-R provides the hardware pulses // that increment the System Tick Timer. pinMode(CLOCK_INPUT_PIN, INPUT); } ```