SY89465U Datasheet, PDF (1/19 Pages) Micrel Semiconductor – Precision LVDS 1:10 Fanout with 2:1 Runt Pulse Eliminator MUX and Internal Termination

SY89465U
Precision LVDS 1:10 Fanout with 2:1 Runt
Pulse Eliminator MUX and Internal Termination
General Description
The SY89465U is a low jitter, 1:10 LVDS fanout
buffer with a 2:1 differential input multiplexer (MUX)
optimized for redundant source switchover
applications. Unlike standard multiplexers, the
SY89465Us 2:1 Runt Pulse Eliminator (RPE) MUX
prevents any short cycles or “runt” pulses during
switchover. In addition, a unique Fail-Safe Input
(FSI) 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, 3-pin internal
termination architecture that allows customers to
interface to any differential signal (AC- or DC-
coupled) as small as 100mV (200mV_PP) without any
level shifting or termination resistor networks in the
signal path. The outputs are LVDS-compatible with
fast rise/fall times guaranteed to be less than 220ps.
The SY89465U operates from a 2.5V ±5% supply
and is guaranteed over the full industrial
temperature range of –40°C to +85°C. The
SY89465U is part of Micrel’s high-speed, Precision
Edge^® product line.
All support documentation can be found on Micrel’s
web site at: www.micrel.com.
Features
Precision Edge^®
• Selects between two sources, and provides 10
precision LVDS copies
• Guaranteed AC performance over temperature and
supply voltage:
– Wide operating frequency: 1kHz to >1.5GHz
– < 1200ps In-to-Out t_pd
– < 220ps t_r/t_f
• Unique, patent-pending input isolation design
minimizes adjacent channel crosstalk
• Fail-Safe Input prevents oscillations
• Ultra-low jitter design:
– <1ps_RMS random jitter
– <1ps_RMS cycle-to-cycle jitter
– <10ps_PP total jitter (clock)
– <0.7ps_RMS MUX crosstalk induced jitter
• Unique patented input termination and VT pin accepts
DC- and AC-coupled inputs (CML, PECL, LVDS)
• 325mV LVDS output swing
• 2.5V ±5% supply voltage
• -40°C to +85°C industrial temperature range
• Output enable
• Available in 44-pin (7mm x 7mm) MLF™ package
Applications
• Redundant clock switchover
• Fail-safe clock protection
Markets
• LAN/WAN
• Enterprise servers
• ATE
• Test and measurement
Precision Edge is a registered trademark of Micrel, Inc.
MLF and MicroLeadFrame are trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
December 2005
M9999-120105-A
[e-mail] or [phone]