MT9043 Zarlink Semiconductor, MT9043 Datasheet - Page 13

• Manufacturer Part Number: MT9043
• Description: T1/E1 System Synchronizer
• Manufacturer: Zarlink Semiconductor

5. TBR 4 November 1995
6. TBR 12 December 1993
7. TBR 13 January 1996
8. ITU-T I.431 March 1993
Applications
This section contains MT9043 application specific details for clock and crystal operation, reset operation, power
supply de coupling, and control operation.
Master Clock
The MT9043 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
the master timing source must be no greater than
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 MT9043 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.
For applications requiring
FOX F7C-2E3-20.0MHz
Frequency:
Tolerance:
Rise & Fall Time:
Duty Cycle:
CTS CB3LV-5I-20.0 MHz
Frequency:
Tolerance:
Rise & Fall Time:
Duty Cycle:
±
100ppm. For applications requiring an accurate Freerun Mode, such as AT&T TR62411, the tolerance of
20MHz
25ppm 0C to 70C
10ns (0.33V 2.97V 15pF)
20MHz
25ppm
10ns
40% to 60%
45% to 55%
±
32ppm clock accuracy, the following clock oscillator module may be used.
Figure 8 - Clock Oscillator Circuit
MT9043
OSCo
OSCi
No Connection
Zarlink Semiconductor Inc.
±
MT9043
32ppm.
20MHz OUT
+3.3V
+3.3V
13
GND
0.1uF
Data Sheet