LMK04816 - Three Input Low Noise Clock Jitter Cleaner with Dual Loop PLLs

The LMK04816 device is the industry’s highest performance clock conditioner with superior clock jitter cleaning, generation, and distribution with advanced features to meet next generation system requirements. The dual-loop PLLATINUM architecture enables 111-fs RMS jitter (12 kHz to 20 MHz) using a low-noise VCXO module or sub-200-fs RMS jitter (12 kHz to 20 MHz) using a low-cost external crystal and varactor diode.

The dual-loop architecture consists of two high-performance phase-locked loops (PLL), a low-noise crystal oscillator circuit, and a high-performance voltage controlled oscillator (VCO). The first PLL (PLL1) provides a low-noise jitter cleaner function while the second PLL (PLL2) performs the clock generation. PLL1 can be configured to either work with an external VCXO module or the integrated crystal oscillator with an external tunable crystal and varactor diode. When used with a very narrow loop bandwidth, PLL1 uses the superior close-in phase noise (offsets below 50 kHz) of the VCXO module or the tunable crystal to clean the input clock. The output of PLL1 is used as the clean input reference to PLL2 where it locks the integrated VCO. The loop bandwidth of PLL2 can be optimized to clean the far-out phase noise (offsets above 50 kHz) where the integrated VCO outperforms the VCXO module or tunable crystal used in PLL1.

• Ultralow RMS Jitter Performance
  • 100-fs RMS Jitter (12 kHz to 20 MHz)
  • 123-fs RMS Jitter (100 Hz to 20 MHz)
• Dual-Loop PLLATINUM™ PLL Architecture
  • PLL1
    • Integrated Low-Noise Crystal Oscillator
      Circuit
    • Holdover Mode When Input Clocks are Lost
      • Automatic or Manual Triggering and
        Recovery
  • PLL2
    • Normalized 1-Hz PLL Noise Floor of
      –227 dBc/Hz
    • Phase Detector Rate Up to 155 MHz
    • OSCin Frequency-Doubler
    • Integrated Low-Noise VCO
    • VCO Frequency Ranges From 2370 MHz
      to 2600 MHz
• Three Redundant Input Clocks With LOS
  • Automatic and Manual Switch-Over Modes
• 50% Duty Cycle Output Divides, 1 to 1045 (Even
  and Odd)
• LVPECL, LVDS, or LVCMOS Programmable
  Outputs
• Precision Digital Delay, Fixed or Dynamically-
  Adjustable
• 25-ps Step Analog Delay Control, Up to 575 ps
• 1/2 Clock Distribution Period Step Digital Delay,
  up to 522 Steps
• 13 Differential Outputs; up to 26 Single-Ended
  • Up to 5 VCXO and Crystal-Buffered Outputs
• Clock Rates of Up to 2600 MHz
• 0-Delay Mode
• Three Default Clock Outputs at Power Up
• Multi-Mode: Dual PLL, Single PLL, and Clock
  Distribution
• Industrial Temperature Range: –40°C to +85°C
• 3.15-V to 3.45-V Operation
• Package: 64-Pin WQFN (9.0 × 9.0 × 0.8 mm)