General Description
The SY89467U is a 2.5/3.3V, 1:20 LVPECL fanout buffer with a 2:1 differential input multiplexer (MUX). A unique Fail-Safe Input (FSI) protection prevents metastable output conditions when the selected input clock fails to a DC voltage (when voltage between the pins of the differential input drops significantly below 100mV).

Features
• Selects between two inputs, and provides 20 precision LVPECL copies
• Fail-Safe Input
    – Prevents outputs from oscillating when input is invalid
• Guaranteed AC performance over temperature and supply voltage:
    – DC-to >1.5 GHz throughput
    – < 1200ps Propagation Delay (In-to-Q)
    – 270ps Rise/Fall times
• Ultra-low jitter design:
    – <1psRMS random jitter
    – <1psRMS cycle-to-cycle jitter
    – <10psPP total jitter (clock)
    – <0.7psRMS MUX crosstalk induced jitter
• Unique, patented MUX input isolation design minimizes adjacent channel crosstalk
• Unique patented internal termination and VT pin accepts DC- and AC-coupled inputs (CML, PECL, LVDS)
• Wide input voltage range: VCC to GND
• 2.5V ±5% or 3.3V ±10% supply voltage
• -40°C to +85°C industrial temperature range
• Available in 64-pin TQFP package

Applications
• Fail-safe clock protection
• SONET clock distribution
• Backplane distribution