Texas Instruments LMK04208 Ultra Low Noise Clock Jitter Cleaner

Texas Instruments LMK04208 Ultra-Low Noise Clock Jitter Cleaner is a high-performance clock conditioner with superior clock jitter cleaning, generation, and distribution. This device includes advanced features to meet next-generation system requirements. The dual loop PLLatinum™ architecture is capable of 111fs, RMS jitter (12kHz to 20MHz) using a low-noise VCXO module or sub-200fs rms jitter (12kHz to 20MHz) 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) of the Texas Instruments LMK04208 provides low-noise jitter cleaner functionality, while the second PLL (PLL2) performs the clock generation.

Features

  • Ultra-low RMS jitter performance
    • 111fs, RMS jitter (12kHz to 20MHz)
    • 123fs, RMS jitter (100Hz to 20MHz)
  • Dual loop PLLatinum™ PLL architecture
  • PLL1:
    • Integrated low-noise crystal oscillator circuit
    • Holdover mode when input clocks are lost
    • Automatic or manual triggering/recovery
  • PLL2:
    • Normalized PLL noise floor of –227dBc/Hz
    • Phase detector rate of up to 155MHz
    • OSCin frequency-doubler
    • Integrated low-noise VCO or external VCO mode
  • Two redundant input clocks with LOS
    • Automatic and manual switch-over modes
  • 50% duty cycle output divides, 1 to 1045 (even and odd)
  • Six LVPECL, LVDS, or LVCMOS programmable outputs
  • Digital delay (fixed or dynamically adjustable)
  • 25ps step analog delay control
  • Seven differential outputs, up to 14 single-ended
    • Up to six VCXO/crystal buffered outputs
  • Clock rates of up to 1536MHz
  • 0-delay mode
  • Three default clock outputs at power-up
  • Multi-mode: dual PLL, single PLL, and clock distribution
  • –40°C to +85°C industrial temperature range 
  • 3.15V to 3.45V operation
  • 64-Pin WQFN package (9mm × 9mm × 0.8mm)

Applications

  • Data converter clocking
  • Wireless infrastructure
  • Networking, SONET/SDH, DSLAM
  • Medical, video, military, and aerospace
  • Test and measurement

Simplified Schematic

Schematic - Texas Instruments LMK04208 Ultra Low Noise Clock Jitter Cleaner
Publicerad: 2016-10-27 | Uppdaterad: 2022-03-11