SY89844U
Precision LVDS Runt Pulse Eliminator 2:1
MUX with 1:2 Fanout and Internal Termination General Description
The SY89844U is a low jitter LVDS, 2:1 input
multiplexer (MUX) optimized for redundant source
switchover
applications.
Unlike
standard
multiplexers, the SY89844U unique 2:1 Runt Pulse
Eliminator (RPE) MUX prevents any short cycles or
“runt” pulses during switchover. In addition, a unique
Fail-Safe Input protection prevents metastable
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
input termination architecture that allows customers
to interface to any differential signal (AC-or DCcoupled) as small as 100mV (200mVpp) without any
level shifting or termination resistor networks in the
signal path. The outputs are 325mV LVDS with fast
rise/fall times guaranteed to be less than 150ps.
The SY89844U operates from a 2.5V В±5% supply …