The **PLL500-17SC-R** is a low-phase-noise, high-performance Phase Locked Loop (PLL) clock multiplier IC designed primarily for crystal-to-output frequency synthesis. It is often used in applications requiring high-stability timing signals. ### 1. Key Specifications The following table summarizes the primary electrical and physical characteristics: | Feature | Specification | | :--- | :--- | | **Manufacturer** | PhaseLink (now part of Microchip/Micrel) | | **Package** | SOIC-8 (Small Outline Integrated Circuit) | | **Input Frequency** | 10MHz to 25MHz (typically via crystal) | | **Output Frequency** | Up to 130MHz (depends on configuration) | | **Operating Voltage** | 3.3V (±10%) | | **Output Type** | CMOS | | **Operating Temperature** | 0°C to 70°C (Commercial Grade) | --- ### 2. Functional Components The IC integrates several internal electronic stages to provide a clean clock signal: * **Crystal Oscillator Circuit:** Designed to work with a fundamental-mode crystal. It includes internal load capacitors to minimize external part count. * **Phase Frequency Detector (PFD):** Compares the reference frequency (input) with the feedback frequency to align the phase. * **Charge Pump & Internal Loop Filter:** Converts the phase error into a control voltage. The internal filter reduces the need for external resistors and capacitors. * **Voltage Controlled Oscillator (VCO):** Generates the high-frequency output signal based on the control voltage. --- ### 3. Pin Configuration (SOIC-8) Below is the typical pinout logic for the PLL500-17 series: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | XIN / CLK | Crystal input or reference clock input | | 2 | XOUT | Crystal output (leave floating if using CLK input) | | 3 | VDD | Power supply (3.3V) | | 4 | OE | Output Enable (Active High) | | 5 | GND | Ground | | 6 | CLKOUT | Main clock output | | 7, 8 | S0, S1 | Multiplier Selection Pins (Sets the output frequency ratio) | --- ### 4. Typical Application Circuit When designing with this part, the layout should minimize noise on the $V_{DD}$ line. ```mermaid graph LR XTAL[Crystal] --- Pin1[XIN] XTAL --- Pin2[XOUT] Power[3.3V Supply] --- Pin3[VDD] Pin6[CLKOUT] --- Load[FPGA / Processor] Decoupling[0.1uF Cap] --- Pin3 ``` ### 5. Benefits and Use Cases * **Low Jitter:** Suitable for telecommunications and high-speed data transfer. * **Space Saving:** The SOIC-8 package and integrated loop filter reduce PCB footprint. * **Flexibility:** The S0/S1 selection pins allow users to change the multiplication factor without replacing hardware. ---