DS3112+W Maxim Integrated Products, DS3112+W Datasheet - Page 132

• Manufacturer Part Number: DS3112+W
• Description: IC MUX T3/E3 3.3V 256-PBGA
• Manufacturer: Maxim Integrated Products

Specifications of DS3112+W

• Controller Type: Framer, Multiplexer
• Interface: Parallel/Serial
• Voltage - Supply: 3.135 V ~ 3.465 V
• Current - Supply: 150mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 256-PBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

14.12 G.747 Framing Structure and E12 Multiplexing
The G.747 frame structure is made up of five 168-bit sets
after another (...Set1/Set2/Set3/Set4/Set5/Set1...) to make up the complete G.747 frame structure. The
Frame Alignment Signal (FAS) is placed in the first 9 bits of Set 1. Set 2 contains the Remote Alarm
Indication (RAI) bit and a Parity Bit (PAR) as well as a reserved bit, which is fixed to a one. The PAR bit
will be set to a one when there are odd numbers of ones from the tributaries in the preceding frame and it
will be set to a zero when there is an even number of ones. The parity calculation does not include the
FAS, RAI, reserved bit, or Justification Control Bits. The three tributaries are bit interleaved starting with
a bit from Tributary 1 immediately after the FAS in Set 1. The first three bits of Sets 3, 4, and 5 are the
Justification Control Bits. Bits 4 to 6 of Set 5 are the Stuffing Bits. The Justification Control bits control
when data will be stuffed into the Stuffing Bit positions. When a majority of the three Justification
Control Bits from a particular tributary is set to zero, the Stuffing Bit position will be used for tributary
data. When the Justification Control Bits are majority decoded to be one, the Stuffing Bit will not be used
for tributary data.
Figure 14-9. G.747 Frame Structure
Set 1
Bit 1
Set 2
Bit 1
Set 3
Bit 1
Set 4
Bit 1
Set 5
Bit 1
NOTE 1:
NOTE 2:
NOTE 3:
NOTE 4:
RAI
c
c
c
FAS (111010000)
11
12
13
BIT 1 OF SET 1 IS TRANSMITTED FIRST.
BJI
CJI
SJ
PAR
c
c
c
21
22
23
TRIBUTARY BITS
JUSTIFICATION CONTROL BITS
STUFFING BITS
c
c
c
1
31
32
33
b
11
s
1
b
21
s
2
b
31
J = TRIBUTARY NUMBER
J = TRIBUTARY NUMBER
J = TRIBUTARY NUMBER
s
3
b
132 of 133
12
...bits from the tributaries...
...bits from the tributaries...
...bits from the tributaries...
b
22
(Figure
b
I = BIT NUMBER
I = CONTROL STUFFING BIT NUMBER
32
...bits from the tributaries...
14-9). The five sets are transmitted one
b
13
...bits from the tributaries...
Bit 168
Bit 168
Bit 168
Bit 168
Bit 168
DS3112