Overview

Description

The IDT8V89308I is a PLL based synchronous multiplier specifically designed for applications utilizing Broadcom PHYs and Switches. This high performance device is optimized for Ethernet / SONET PDH frequency translation and clock jitter attenuation. The device contains two internal frequency multiplication stages that are cascaded in series. The first stage is a low bandwidth PLL that is optimized to provide reference clock jitter attenuation. The second stage is a FemtoClock® frequency multiplier that provides the low jitter, high frequency Ethernet output clock that easily meets Gigabit and 10 Gigabit Ethernet jitter requirements. Pre-divider and output divider multiplication ratios are selected using device selection control pins. The multiplication ratios are optimized to support most common clock rates used in Ethernet, SONET, PDH applications. IDT8V89308I requires the use of an external, inexpensive fundamental mode crystal and uses external passive loop filter components which allows configuration of the PLL loop bandwidth and damping characteristics. The device is packaged in a space-saving 32-VFQFN package and supports industrial temperature range.

Features

  • Two LVPECL output pairs Each output supports independent frequency selection at 25MHz, 125MHz and 156.25MHz
  • One differential input supports the following input types: LVPECL, LVDS
  • Accepts input frequencies 8kHz, 25MHz,125MHz and 155.52MHz
  • First stage PLL bandwidth can be optimized for jitter attenuation and reference tracking using external loop filter connection
  • FemtoClock frequency multiplier provides low jitter, high frequency output
  • Absolute pull range: 50ppm
  • FemtoClock VCO frequency: 625MHz
  • RMS phase jitter @ 25MHz, using a 25MHz crystal (12kHz '- 5MHz): 0.238ps (typical), 0.30ps (maximum)
  • RMS phase jitter @ 125MHz, using a 25MHz crystal (12kHz '- 20MHz): 0.223ps (typical), 0.30ps (maximum)
  • RMS phase jitter @ 156.25MHz, using a 25MHz crystal (12kHz '- 20MHz): 0.223ps (typical), 0.30ps (maximum)
  • 3.3V supply voltage
  • -40°C to 85°C ambient operating temperature
  • Available in lead-free (RoHS 6) package

Comparison

Applications

Documentation

Design & Development

Models