82V2608BB IDT, Integrated Device Technology Inc, 82V2608BB Datasheet - Page 21

• Manufacturer Part Number: 82V2608BB
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of 82V2608BB

• Utopia Level: Level 2
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 2.97V
• Operating Supply Voltage (max): 3.63V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Package Type: BGA
• Pin Count: 208
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Not Compliant

Spaced Mapping
signed (i.e., 4, 8, 12, 16, 20, 24 and 28). Refer to Figure-6. Suppose T1
time slot x is mapped to E1 time slot y. We have y=x+int((x-1)/3), where
IDT82V2608
INTERFACE
In this mode, T1 to E1 mapping makes every fourth time slot unas-
1.5 M T1
Stream
1.5 M T1
stream
2 M E1
stream
Stream
2 M
F
time slot
Framing
F
A
A
E1
F
u
0
X
A
0
1
1. X=unused bits
2. u=unassigned time slot
3. F
4. Mapping rule: If T1 time slot x is mapped to E1 time slot y, y = x+int(x/3). Here int(n) is
the largest integer no greater than n.
1. X=unused bit
2. u=unassigned time slot
3. F
1
1
X
1
2
A
A
, F
, F
2
2
X
2
B
B
3
and F
and F
X
3
4
C
C
X
are T1 framing bits for frame A, B and C respectively.
4
are T1 framing bits for frame A, B and C respectively.
u
5
Frame A
X
14 15 16 17 18
14 15 16 17 18
5
6
Frame A
Figure-6 Spaced Mapping Mode
Figure-5 G.802 Mapping Mode
X
6
signalling
time slot
7
E1
u
7
8
u
8
9
9
21
F
22
B
int(n) is the largest integer no greater than n. The framing bit is assigned
to the first bit of TS0. This distribution of unassigned time slots averages
out the idle time slots and optimizes the framer’s slip buffer’s usage.
23 24 F
X
23 24 F
24 25 26 27 28
27 28
X
u
X
B
F
B
B
29
X
1
X
1
u
30
X
2
X
2
u
31
X
Frame B
Frame B
X
u
0
X
X
1
31
Inverse Multiplexing for ATM
u
23 24 F
X
23 24 F
2
u
0
X
1
X
C
December 4, 2006
C
2
1
31
1
2
2