MT9045AN Zarlink Semiconductor, Inc., MT9045AN Datasheet - Page 15

• Manufacturer Part Number: MT9045AN
• Description: Framer, Framer Circuit, T1/E1/OC3 System Synchronizer
• Manufacturer: Zarlink Semiconductor, Inc.

MT9045
Data Sheet
MT9045 provides a fast lock pin (FLOCK), which, when set high enables the PLL to lock to an incoming
reference within approximately 500 ms.
MT9045 and Network Specifications
The MT9045 fully meets all applicable PLL requirements (intrinsic jitter/wander, jitter/wander tolerance,
jitter/wander transfer, frequency accuracy, frequency holdover accuracy, capture range, phase change slope
and MTIE during reference rearrangement) for the following specifications.
1. Bellcore GR-1244-CORE June 1995 for Stratum 3, Stratum 4 Enhanced and Stratum 4
2. AT&T TR62411 (DS1) December 1990 for Stratum 3, Stratum 4 Enhanced and Stratum 4
3. ANSI T1.101 (DS1) February 1994 for Stratum 3, Stratum 4 Enhanced and Stratum 4
4. ETSI 300 011 (E1) April 1992 for Single Access and Multi Access
5. TBR 4 November 1995
6. TBR 12 December 1993
7. TBR 13 January 1996
8. TU-T I.431 March 1993
9. TU-T G.813 August 1996 for Option1 clocks for 2048 kbit/s interfaces
10. ITU-T G.812 June 1998 for type IV clocks for 1,544 kbit/s interfaces and 2,048 kbit/s interfaces
Applications
This section contains MT9045 application specific details for clock and crystal operation, reset operation, power
supply decoupling, and control operation.
Master Clock
The MT9045 can use either a clock or crystal as the master timing source.
In Freerun Mode, the frequency tolerance at the clock outputs is identical to the frequency tolerance of the
source at the OSCi pin. For applications not requiring an accurate Freerun Mode, tolerance of the master timing
±
source may be
100ppm. For applications requiring an accurate Freerun Mode, such as AT&T TR62411, the
±
tolerance of the master timing source must be no greater than
32ppm.
Another consideration in determining the accuracy of the master timing source is the desired capture range.
The sum of the accuracy of the master timing source and the capture range of the MT9045 will always equal
230ppm. For example, if the master timing source is 100ppm, then the capture range will be 130ppm.
Clock Oscillator - when selecting a Clock Oscillator, numerous parameters must be considered. This includes
absolute frequency, frequency change over temperature, output rise and fall times, output levels and duty cycle.
Zarlink Semiconductor Inc.
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