The **PLL500-16SC-R** is a low-cost, high-performance **VCXO (Voltage Controlled Crystal Oscillator)** IC manufactured by Microchip Technology (originally PhaseLink). It is specifically designed to work with fundamental crystals to generate a low-jitter output clock. --- ### ## 1. Key Specifications The following table highlights the primary technical parameters of the device: | Feature | Specification | | :--- | :--- | | **Function** | VCXO (Voltage Controlled Crystal Oscillator) | | **Frequency Range** | 1 MHz to 36 MHz | | **Supply Voltage (VDD)** | 2.25V to 3.63V | | **Output Type** | CMOS | | **Control Voltage (VC)** | 0V to VDD | | **Package Type** | SOP-8 (Standard 8-pin Small Outline) | | **Pullability Range** | ±100 ppm to ±200 ppm (typical) | | **Operating Temperature** | 0°C to +70°C (Standard) | --- ### ## 2. Core Functional Components The IC integrates several critical electronic stages to ensure precise frequency control: 1. **Crystal Oscillator Circuit:** Designed to interface with a fundamental mode crystal. It uses the crystal's mechanical resonance to establish a stable reference frequency. 2. **Varactor Diodes:** Internal voltage-variable capacitors (varactors) are used to "pull" or tune the crystal's frequency based on the voltage applied to the **VC** pin. 3. **Phase-Locked Loop (PLL) / Buffer:** While the 500-16 series is primarily a VCXO, it includes buffering circuitry to drive CMOS loads with minimal phase noise. 4. **Output Enable (OE):** A digital input pin that allows the user to enable or disable the clock output for power saving or system synchronization. --- ### ## 3. Pin Configuration (SOP-8) To use this part in a circuit, the following pinout is standard: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **VC** | Voltage Control input for frequency tuning. | | 2 | **XIN** | Crystal input connection. | | 3 | **GND** | Ground connection. | | 4 | **XOUT** | Crystal output connection. | | 5 | **CLK** | CMOS Clock Output. | | 6 | **VDD** | Power supply (typically 3.3V). | | 7 | **OE** | Output Enable (High = Active, Low = High Impedance). | | 8 | **NC/FIN** | No connection or Frequency Input (variant dependent). | --- ### ## 4. Common Applications * **Set-Top Boxes:** Used for clock recovery in video streams. * **Networking:** Synchronizing data transfers in ADSL or Ethernet equipment. * **Audio/Video:** Precise timing for DACs (Digital-to-Analog Converters) to reduce jitter-induced distortion. * **Frequency Synthesis:** Acting as a tunable reference for larger PLL systems. --- ### ## 5. Part Number Breakdown * **PLL500-16**: Base part family (VCXO). * **S**: SOP Package. * **C**: Commercial temperature range. * **-R**: Tape and Reel packaging (for automated assembly).