XRT84L38IB Exar Corporation, XRT84L38IB Datasheet - Page 279

• Manufacturer Part Number: XRT84L38IB
• Description: Network Controller & Processor ICs 8 Ch T1/E1 Framer
• Manufacturer: Exar Corporation

Specifications of XRT84L38IB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

REV. 1.0.1
The table below shows the combinations of Transmit Multiplex Enable bit and Transmit Interface Mode Select
[1:0] bits and the resulting Transmit Back-plane Interface data rates.
When the Transmit Multiplex Enable bit is set to zero, the framer is configured in non-channel-multiplexed
mode. The possible data rates are XRT84V24 Compatible 2.048Mbit/s, MVIP 2.048Mbit/s, 4.096Mbit/s and
8.192Mbit/s. In non-channel-multiplexed mode, payload data of each channel are taken from the Terminal
Equipment separately. Each channel uses its own Transmit Serial Clock, Transmit Serial Data, Transmit
Single-frame Synchronization signal and Transmit Multi-frame Synchronization signal as interface between the
framer and the Terminal Equipment. Section 1.1.2.1, 1.1.2.2 and 1.1.2.3 provide details on how to connect the
Transmit Payload Data Interface block with the Terminal Equipment when the Back-plane interface data rate is
1.544Mbit/s.
When the Back-plane interface data rate is MVIP 2.048Mbit/s, 4.096Mbit/s and 8.192Mbit/s, the Transmit
Serial Clock, Transmit Serial Data, Transmit Single-frame Synchronization signal and Transmit Multi-frame
Synchronization signal are all configured as inputs. The Transmit Serial Clock is always an input clock with
frequency of 2.048 MHz for all data rates. The TxMSync_n signal is configured as the Transmit Input Clock
with frequencies of 2.048 MHz, 4.096 MHz and 8.192 MHz respectively. It serves as the primary clock source
for the High-speed Back-plane Interface.
The table below summaries the clock frequencies of TxSerClk_n and TxInClk_n inputs when the framer is
operating in non-multiplexed High-speed Back-plane mode.
TRANSMIT MULTIPLEX ENABLE BIT = 0
When the Transmit Multiplex Enable bit is set to one, the framer is configured in channel-multiplexed mode.
The possible data rates are bit-multiplexed 16.384Mbit/s, HMVIP 16.384Mbit/s and H.100 16.384Mbit/s. In
channel-multiplexed mode, every four channels share the Transmit Serial Data and Transmit Single-frame
Synchronization signal of one channel as interface between the framer and the local Terminal Equipment. The
TxMSync_n signal of one channel is configured as the Transmit Input Clock with frequencies of 16.384 MHz. It
serves as the primary clock source for the High-speed Back-plane Interface.
Payload and signaling data of Channel 0-3 are multiplexed onto the Transmit Serial Data pin of Channel 0.
Payload and signaling data of Channel 4-7 are multiplexed onto the Transmit Serial Data pin of Channel 4. The
T
M
T
RANSMIT
ODE
RANSMIT
E
S
NABLE
ELECT
0
0
1
1
I
NTERFACE
0
0
0
0
1
1
1
1
M
ULTIPLEX
B
B
IT
IT
1
T
M
RANSMIT
ODE
T
M
RANSMIT
ODE
S
ELECT
0
1
0
1
I
NTERFACE
S
ELECT
0
0
1
1
0
0
1
1
I
NTERFACE
B
IT
0
B
IT
1
I
NTERFACE
MVIP 2.048Mbit/s
B
2.048Mbit/s
4.096Mbit/s
8.192Mbit/s
ACK
T
M
RANSMIT
259
ODE
-
PLANE
D
ATA
S
ELECT
R
0
1
0
1
0
1
0
1
I
NTERFACE
ATE
B
IT
0
2.048 MHz
2.048 MHz
2.048 MHz
2.048 MHz
T
X
S
B
XRT84V24 Compatible 2.048Mbit/s
ER
ACK
C
Bit Multiplexed 16.384Mbit/s
LK
-
OCTAL T1/E1/J1 FRAMER
PLANE
HMVIP 16.384Mbit/s
H.100 16.384Mbit/s
MVIP 2.048Mbit/s
4.096Mbit/s
8.192Mbit/s
I
NTERFACE
T
-
X
MS
2.048 MHz
4.096 MHz
8.192 MHz
XRT84L38
YNC
D
-
ATA
/T
X
I
N
R
C
ATE
LK