tmxf28155 ETC-unknow, tmxf28155 Datasheet - Page 571

• Manufacturer Part Number: tmxf28155
• Description: Tmxf28155 Super Mapper 155/51 Mbits/s Sonet/sdh X28/x21 Ds1/e1
• Manufacturer: ETC-unknow

Preliminary Data Sheet
May 2001
23 Digital Jitter Attenuation Controller Functional Description
23.1 Introduction
This section describes the functions of the digital jitter attenuator (DJA) controller used in the Super Mapper device.
The DJA controller contains 28 DJA blocks. Each DJA block can operate in two different modes, as a DS1 or an E1
jitter attenuator. In both modes, the DJA blocks can be provisioned to operate as a second-order PLL always, or it
can switch to act as a first-order PLL during VT pointer adjustments to help meet MTIE requirements. The block will
also insert the proper AIS signal if the primary block AIS control input is active. The PLL bandwidth can be set over
a wide range to accommodate a number of different system constraints.
23.2 Features
Figure 98
Agere Systems Inc.
The DJA block accepts/delivers DS1/E1 clock, data, and AIS indications from/to the cross connect block.
AIS in will cause the correct AIS clock to be inserted, and the AIS indication will be passed back to the cross con-
nect.
The DJA blocks operate in the second-order PLL mode under normal conditions. The DJA blocks can be provi-
sioned to enter the first-order PLL mode following VT level pointer adjustments. The period of time in the first-
order mode is provisionable via registers.
The PLL bandwidth is provisionable between 0.1 Hz and 0.5 Hz. The damping factor for these bandwidths varies
between 2 and 0.5.
shows the DJA block with I/O connections to other blocks within the Super Mapper device.
E1_XCLK
D S1_XC LK
Figure 98. DJA Block with I/O Connections to Other Blocks in the Device
M IC R O IN TER FAC E
AT TEN UAT OR
DIGIT AL
JITTER
C ONT RO L
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
XC _JD ATA[28:1]
XC _JC LK[28:1]
XC _JPTR ADJ[28:1]
XC _JAIS[28:1]
D JA_C LK[28:1]
D JA_D ATA[28:1]
D S1_AISC LK
E1_AISCLK
TMXF28155/51 Super Mapper
(continued)
C ON NEC T
CR OSS
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