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Precision Edge
®
SY89875U
Micrel, Inc.
M9999-082407
hbwhelp@micrel.com or (408) 955-1690
DESCRIPTION
Integrated programmable clock divider and 1:2
fanout buffer
Guaranteed AC performance over temperature and
voltage:
• > 2.0GHz f
MAX
• < 200ps t
r
/t
f
• < 15ps within device skew
Low jitter design:
• < 10ps
PP
total jitter
• < 1ps
RMS
cycle-to-cycle jitter
Unique input termination and V
T
Pin for DC-coupled
and AC-coupled Inputs; CML, PECL, LVDS and
HSTL
LVDS compatible outputs
TTL/CMOS inputs for select and reset
Parallel programming capability
Programmable divider ratios of 1, 2, 4, 8 and 16
Low voltage operation 2.5V
Output disable function
–40°C to 85°C temperature range
Available in 16-pin (3mm x 3mm) MLF
®
package
FEATURES
2.5V, 2.0GHz ANY DIFF. IN-TO-LVDS
PROGRAMMABLE CLOCK DIVIDER AND 1:2
FANOUT BUFFER W/ INTERNAL TERMINATION
Precision Edge
®
SY89875U
APPLICATIONS
SONET/SDH line cards
Transponders
High-end, multiprocessor servers
Rev.: D Amendment: /0
Issue Date: August 2007
This low-skew, low-jitter device is capable of accepting a
high-speed (e.g., 622MHz or higher) CML, LVPECL, LVDS
or HSTL clock input signal and dividing down the frequency
using a programmable divider to create a lower speed
version of the input clock. Available divider ratios are 2, 4, 8
and 16, or straight pass-through.
The differential input buffer has a unique internal
termination design that allows access to the termination
network through a V
T
pin. This feature allows the device to
easily interface to different logic standards. A V
REF-AC
reference is included for AC-coupled applications.
The /RESET input asynchronously resets the divider. In
the pass-through function (divide by 1) the /RESET
synchronously enables or disables the outputs on the next
falling edge of IN (rising edge of /IN).
FUNCTIONAL BLOCK DIAGRAM
TYPICAL PERFORMANCE
Precision Edge is a registered trademark of Micrel, Inc.
MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc.
9
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Divide-by-4
C
ML/LVPECL/LVDS
622MHz
Clock In
OC-12 to OC-3
Translator/Divider
LVDS
155.5MH
z
Clock Ou
t
622MHz In
/
Q0
Q0
/IN
IN
155.5MHz Out
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