Volver a Renesas Electronics

Renesas Electronics 9ZXL1231E & 9ZXL1251E Clock Buffers

Renesas Electronics 9ZXL1231E and 9ZXL1251E Clock Buffers are 2nd generation enhanced-performance 12-output DB1200ZL differential buffers for PCIe Gen1-4 and UPI. These Renesas Electronics 9ZXL1231E / 9ZXL1251E buffers are pin-compatible upgrades to the 9ZXL1231A and 9ZLX1251A clock buffers offer a much-improved phase jitter performance and increased system security features. The 9ZXL1231E / 9ZXL1251E buffers offer fixed external feedback, which maintains low drift for critical QPI/UPI applications. Typical applications include servers, storage, networking, and Solid State Drives (SSD).

Features

  • LP-HCSL outputs eliminate 24 resistors and save 41mm2 of area (1231E)
  • Selectable PLL BW minimizes jitter peaking in cascaded PLL topologies
  • 12 OE# pins are hardware control of each output
  • Spread spectrum compatible tracks spreading input clock for EMI reduction
  • Hardware/SMBus control of PLL bandwidth and bypass changes mode without a power cycle
  • PCIe clocking architectures supported
    • Common Clocked (CC)
    • Independent Reference (IR) with and without spread spectrum
  • Output features
    • 12 Low-Power (LP) HCSL output pairs with 85Ω Zout (1251E)
    • 12 Low-Power (LP) HCSL output pairs (1231E)

Specifications

  • Less than 50ps cycle-to-cycle jitter 
  • Less than 50ps output-to-output skew
  • Input-to-output delay fixed at 0ps
  • Less than 50ps input-to-output delay variation
  • Less than 0.5ps rms PCIe Gen4 phase jitter
  • Phase jitter QPI/UPI > = 9.6GB/s < 0.2ps rms
  • Less than < 1.0ps rms phase jitter IF-UPI

Applications

  • Servers
  • Storage
  • Networking
  • SSDs

Block Diagram

Block Diagram - Renesas Electronics 9ZXL1231E & 9ZXL1251E Clock Buffers
Publicado: 2018-07-09 | Actualizado: 2023-02-01