SY89464U
Precision LVPECL 1:10 Fanout with 2:1 Runt
Pulse Eliminator MUX and Internal Termination General Description
The SY89464U is a low jitter 1:10 LVPECL fanout
buffer with a 2:1 differential input multiplexer (MUX)
optimized for redundant source switchover
applications. Unlike standard multiplexers, the
SY89464U’s unique 2:1 Runt Pulse Eliminator
(RPE) MUX prevents any short cycles or “runt”
pulses during switchover. In addition, a unique FailSafe Input (FSI) protection prevents metastable
output conditions when the selected input clock fails
to a DC voltage (voltage between the pins of the
differential input drops below 100mV).
The differential input includes Micrel’s unique, 3-pin
internal termination architecture that allows
customers to interface to any differential signal (ACor DC-coupled) as small as 100mV (200mVPP)
without any level shifting or termination resistor
networks in the signal path. The outputs are 800mV,
100K-compatible LVPECL with fast rise/fall times
guaranteed to be less than 220ps.
The SY89464U operates from a 2.5V В±5% or 3.3V
В±10% supply and is guaranteed over the full
industrial temperature range of –40В°C to +85В°C. The …