MK2059-01 Datasheet, PDF (1/10 Pages) Integrated Circuit Systems – VCXO-Based Frame Clock Frequency Translator

MK2059-01
VCXO-Based Frame Clock Frequency Translator
Description
The MK2059-01 is a VCXO (Voltage Controlled Crystal
Oscillator) based clock generator that produces
common telecommunications reference frequencies.
The output clock is phase locked to an 8kHz (frame
rate) input reference clock. The MK2059-01 also
provides jitter attenuation. Included in the selection of
output frequencies are these common system clocks:
1.544 MHz (T1)
2.048 (E1)
19.44 MHz (OC-3)
16.384 MHz (8x E1)
This monolithic IC, combined with an external
inexpensive quartz crystal, can be used to replace a
more costly hybrid VCXO retiming module. Through
selection of external loop filter components, the PLL
loop bandwidth and damping factor can be tailored to
meet input clock jitter attenuation requirements. A loop
bandwidth down to the Hz range is possible.
Features
• Generates T1, E1, OC-3 and other common telecom
clock frequencies from an 8kHz frame clock
• Configurable jitter attenuation characterisitics,
excellent for use as a Stratum source de-jitter circuit
• 2:1 Input MUX for input reference clocks
• VCXO-based clock generation offers very low jitter
and phase noise generation
• Output clock is phase and frequency locked to the
selected input reference clock
• Fixed input to output phase relationship
• +115ppm minimum crystal frequency pullability
range, using recommended crystal
• Industrial temperature range
• Low power CMOS technology
• 20 pin SOIC package
• Single 3.3V power supply
Block Diagram
8kHz Ref Input ^ICLK2
1
8kHz Ref Input ^ICLK1
0
ISEL
3
S E L 2 :0
IS E T
Phase
D e te c to r
Charge
Pump
Pullable xtal
X1
X2
VDD
VDD ³
VCXO
Output
D iv id e r
Feedback
Divider
CHGP
VIN
GND 4
CLK
MDS 2059-01 B
1
Revision 071001
Integrated Circuit Systems, Inc. q 525 Race Street, San Jose, CA 95126 q tel [phone] q www.icst.com