XRT94L31IB Exar Corporation, XRT94L31IB Datasheet - Page 26

• Manufacturer Part Number: XRT94L31IB
• Description: IC MAPPER DS3/E3/STS-1 504TBGA
• Manufacturer: Exar Corporation

Specifications of XRT94L31IB

• Applications: Network Switches
• Interface: Bus
• Voltage - Supply: 3.14 V ~ 3.47 V
• Package / Case: 504-LBGA
• Mounting Type: Surface Mount
• Product: Mapper
• Lead Free Status / RoHS Status: Contains lead / RoHS Compliant

XRT94L31
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC
PIN DESCRIPTION OF THE XRT94L31 (REV. B)
PIN #
E10
D11
C8
B6
B8
TXPOHENABLE
SIGNAL NAME
TXPOHINS
TxPOH_0
TxPOH_1
TxPOH_2
I/O
O
I
I
TTL
TTL
TTL
TYPE
Transmit Path Overhead Input Port - Insert Enable Input pin:
This pin is used for the Transmit AU-4/VC-4 Mapper POH Processor
Block when TUG-3 mapping is used.
These input pins, along with TxPOH, TxPOHEnable, TxPOHFrame and
TxPOHClk function as the Transmit Path Overhead (TxPOH) Input
Port.These input pins are used to enable or disable the TxPOH input
port.
If these input pins are pulled "High", then the TxPOH port will sample
and latch data via the corresponding TxPOH input pins, upon the falling
edge of TxPOHClk.
N
Transmit Path Overhead Input Port - POH Indicator Output pin:
This pin is used for the Transmit AU-4/VC-4 Mapper POH Processor
Block when TUG-3 mapping is used.
Th[s output pins, along with TxPOH, TxPOHIns, TxPOHFrame and
TxPOHClk function as the Transmit Path Overhead (TxPOH) Input Port.
These output pins will pulse "High" anytime the TxPOH port is ready to
accept and process POH bytes. These output pins will be "Low" at all
other times.
Transmit Path Overhead Input Port - Input pin.
These input pins are used to insert the POH data into each of the 3
Transmit SONET POH Processor blocks (for insertion and transmission
via the outbound STS-3 signal.If the user is only inserting POH data via
these input pins:
In this mode, the external circuitry (which is being interfaced to the
Transmit Path Overhead Input Port is suppose to monitor the following
output pins;
TxPOHFrame_n
TxPOHEnable_n
TxPOHClk_n
The TxPOHFrame_n output pin will toggle "High" upon the rising edge of
TxPOHClk_n approximately one TxPOHClk_n period prior to the TxPOH
port being ready to accept and process the first bit within J1 byte (e.g.,
the first POH byte). The TxPOHFrame_n output pin will remain "High"
for eight consecutive TxPOHClk_n periods. The external circuitry should
use this pin to note STS-1 SPE frame boundaries.
The TxPOHEnable_n output pin will toggle "High" upon the rising edge
of TxPOHClk_n approximately one TxPOHClk_n period prior to the
TxPOH port being ready to accept and process the first bit within a given
POH byte.
To externally insert a given POH byte:
This data bit will be sampled upon the very next falling edge of
TxPOHClk_n. The external circuitry should continue to keep the
TxPOHIns_n input pin "High" and advancing the next bits (within the
POH bytes) upon each rising edge of TxPOHClk_n.
OTE
a. assert the TxPOHIns_n input pin by toggling it "High", and
b. place the value of the first bit (within this particular POH byte) on
: Conversely, if these input pins are pulled "Low", then the TxPOH
this input pin upon the very next rising edge of TxPOHClk_n.
port will NOT sample and latch data via the corresponding
TxPOH input pins.
26
DESCRIPTION
REV. 1.0.1