The **MCS3AS** is a surface-mount (SMD) quartz crystal oscillator, primarily used in high-frequency applications where miniaturization and precision are critical. It is commonly utilized in telecommunications, consumer electronics, and industrial equipment. ### 1. General Specifications The MCS3AS typically features the following technical characteristics: | Feature | Specification Details | | :--- | :--- | | **Package Type** | SMD (Surface Mount Device) | | **Package Size** | ~3.2mm x 2.5mm | | **Frequency Range** | 10.0 MHz to 125.0 MHz (typical) | | **Supply Voltage (Vdd)** | 1.8V, 2.5V, or 3.3V (model dependent) | | **Frequency Stability** | ±20ppm to ±100ppm | | **Output Type** | CMOS / HCMOS | --- ### 2. Pin Configuration The MCS3AS usually follows a standard 4-pin layout. Below is the typical pinout: 1. **Pin 1 (Enable/Disable):** High level or open allows oscillation; Low level stops oscillation (High Impedance). 2. **Pin 2 (Ground):** Connects to the system ground. 3. **Pin 3 (Output):** The clock signal output. 4. **Pin 4 (Supply Voltage):** Connects to the positive power supply. --- ### 3. Key Electronic Characteristics * **Low Phase Jitter:** Designed for timing-sensitive circuits to ensure data integrity during high-speed transmissions. * **Tri-state Function:** Pin 1 allows the output to be "disconnected" electronically, which is useful for testing or power-saving modes. * **Hermetic Sealing:** Usually ceramic-packaged with a metal lid to protect the quartz crystal from environmental moisture and aging. --- ### 4. Typical Application Circuit When integrating the MCS3AS, it is standard practice to include a decoupling capacitor. ```mermaid graph LR VCC((Vcc)) --- C1[0.01uF Capacitor] C1 --- GND((GND)) VCC --- Pin4[Pin 4: Vdd] Pin1[Pin 1: OE] --- VCC Pin2[Pin 2: GND] --- GND Pin3[Pin 3: OUT] --- MCU[Microcontroller/IC] ``` ---