MK2049-35
3.3 V Communications Clock PLL
Description
The MK2049-35 is a Phase-Locked Loop (PLL)
based clock synthesizer that accepts multiple input
frequencies. With an 8 kHz clock input as a
reference, the MK2049-35 generates T1, E1, T3,
E3, OC3/3, Gigabit Ethernet, and other
communications frequencies. This allows for the
generation of clocks frequency-locked to an 8 kHz
backplane clock, simplifying clock synchronization
in communications systems.
This part also has a jitter-attenuated Buffer
capability. In this mode, the MK2049-35 is ideal
for filtering jitter from with high jitter clocks.
ICS/MicroClock can customize these devices for
many other different frequencies. Contact your
ICS/MicroClock representative for more details.
Features
• Packaged in 20 pin SOIC
• 3.3 V ±5% operation
• Meets the TR62411, ETS300 011, and GR-1244
specification for MTIE, Pull-in/Hold-in Range,
Phase Transients, and Jitter Generation for
Stratum 3, 4, and 4E
• Accepts multiple inputs: 8 kHz backplane clock,
or 10 to 50 MHz
• Locks to 8 kHz ±100 ppm (External mode)
• Buffer Mode allows jitter attenuation of
10-50 MHz input and x1/x0.5 or x1/x2 outputs
• Exact internal ratios enable zero ppm error
• Output clock rates include T1, E1, T3, E3,
and OC3 submultiples
• See the MK2049-01, -02, and -03 for more
selections at VDD = 5 V, and the MK2049-34 for
more selections at 3.3 V
GND
3
RES
Block Diagram
VDD
3
FS3:0
4
Clock
Input
Reference
X1
Crystal
Crystal
Oscillator
X2
External/
Buffer Mode
Mux
PLL
Clock
Synthesis,
Control, and
Jitter
Attenuation
Circuitry
Output
Buffer
Output
Buffer
Output
Buffer
CLK
CLK/2
8 kHz
(External
Mode only)
FCAP
CAP1
CAP2
1
Revision 121300
Integrated Circuit Systems, Inc. • 525 Race Street • San Jose • CA • 95126 • (408)295-9800tel• www.icst.com
MDS 2049-35 A
ICS [ INTEGRATED CIRCUIT SYSTEMS ]
