XRT75R12DIB-F Exar Corporation, XRT75R12DIB-F Datasheet - Page 124

• Manufacturer Part Number: XRT75R12DIB-F
• Description: Peripheral Drivers & Components (PCIs) 12 Channel 3.3V-5V temp -45 to 85C
• Manufacturer: Exar Corporation

Specifications of XRT75R12DIB-F

• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 3.3 V to 5 V
• Package / Case: TBGA-420
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XRT75R12D
TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
During this effort, we learned the following.
MAJOR PATTERN A
MAJOR PATTERN A consists of two "sub" or minor-patterns, (which we will refer to as "MINOR PATTERN P1
and P2).
MINOR PATTERN P1 consists of a string of seven (7) clock pulses, followed by a single gap (no clock pulse).
An illustration of MINOR PATTERN P1 is presented below in Figure 65.
It should be noted that each of these clock pulses has a period of approximately 19.3ns (or has an
"instantaneously frequency of 51.84MHz).
MINOR Pattern P2 consists of string of five (5) clock pulses, which is also followed by a single gap (no clock
pulse). An illustration of Pattern P2 is presented below in
HOW MAJOR PATTERN A IS SYNTHESIZED
MAJOR PATTERN A is created (by the Mapper IC) by:
F
F
1.
IGURE
IGURE
Repeating MINOR PATTERN P1 (e.g., 7 clock pulses, followed by a gap) 63 times.
Upon completion of the 63rd transmission of MINOR PATTERN P1, MINOR PATTERN P2 is transmitted
repeatedly 36 times.
This "DS3 Clock" and "Data" signal, which is output from the Mapper IC consists of two major "repeating"
patterns (which we will refer to as "MAJOR PATTERN A" and "MAJOR PATTERN B". The behavior of
each of these patterns is presented below.
65. I
66. I
LLUSTRATION OF
LLUSTRATION OF
1
1
MINOR PATTERN P1
MINOR PATTERN P2
2
2
3
3
4
4
120
5
5
Figure
6
66.
Missing Clock Pulse
Missing Clock Pulse
7
REV. 1.0.3