ST70235A STMicroelectronics, ST70235A Datasheet - Page 12

• Manufacturer Part Number: ST70235A
• Description: Transceiver 144-Pin TQFP
• Manufacturer: STMicroelectronics

Specifications of ST70235A

• Package: 144TQFP
• Power Supply Type: Analog
• Typical Operating Supply Voltage: 1.8|3.3 V
• Minimum Operating Supply Voltage: 1.62|3 V
• Maximum Operating Supply Voltage: 1.98|3.6 V
• Case: QFP

ST70235A
Figure 6 : Generic TC Layer Functions
ATM Specific TC Layer Functions
The 2 bytes streams (fast and slow) are received
from the byte-based processing unit. When ATM
cells are transported, this block provides basic cell
functions such as cell synchronization, cell
payload descrambling, idle/unassigned cell filter,
cell Header Error Correction (HEC) and detection.
The cell processing happens according to ITU-T
I.163 standard. Provision is also made for BER
Figure 7 : ATM Specific TC Layer Functions
Figure 8 : Interface Module
12/28
To/From
Demapper
DATA PATX MERGER
From
Generic
TC
DE-INTERLEAVER
INTERLEAVER
From
ATM
TC
SLOW
FAST
SLOW ATM
FAST ATM
CELL SCRAMBLER
CELL SCRAMBLER
FAST
SYNCHRONIZER
SYNCHRONIZER
DESCRAMBLER
DESCRAMBLER
DECODING
CODING
RS
measurements at this ATM cell level. When non
cell oriented byte streams are transported, the cell
processing unit is not active. The interface module
collects cells (from the cell-based function
module). Cells are stored in FIFO’s (424 bytes or
8 cell wide, transmit buffers have the same size),
from which they are extracted by 2 interface
submodules, one providing a Utopia level 1
interface and the other a Utopia level 2 interface.
HEC
HEC
UTOPIA
UTOPIA
UTOPIA
UTOPIA
F
I
DESCRAMBLER
DESCRAMBLER
INSERTION/
INSERTION/
SCRAMBLER
SCRAMBLER
LEVEL
LEVEL
LEVEL
LEVEL
FILTER
FILTER
CELL
CELL
BER
BER
1
2
1
2
PMD
PMD
Indication Bits AOC EOC
To
Interface
Module
DEFRAMER
FRAMER
F
I
To
ATM
TC