XRT94L33IB-L Exar Corporation, XRT94L33IB-L Datasheet - Page 23

• Manufacturer Part Number: XRT94L33IB-L
• Description: IC MAPPER DS3/E3/STS-1 504TBGA
• Manufacturer: Exar Corporation

Specifications of XRT94L33IB-L

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

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3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
F8
E8
TxTOHFrame
TxTOH
O
I
CMOS
TTL
Transmit TOH Input Port – Input pin:
This input pin, along with the “TxTOHIns” input pin, the
“TxTOHEnable” and “TxTOHFrame” and “TxTOHClk” output
pins function as the “Transmit TOH Input Port”.
To externally insert user values of TOH into the outbound
STS-3 data stream via the “Transmit TOH Input Port”, do the
following.
•
“TxTOHEnable” upon the rising edge of “TxTOHClk.
• Whenever “TxTOHEnable” pulses “HIGH”, then the user’s
external circuitry should drive the “TxTOHIns” input pin
“HIGH”.
• Next, the user should output the next TOH bit, onto this
input pin, upon the rising edge of “TxTOHClk”. The “Transmit
TOH Input Port” will sample the data (on this input pin) upon
the falling edge of “TxTOHClk”.
Note:
Transmit TOH Input Port – STS-3/STM-1 Frame Indicator:
This output pin, along with “TxTOHClk”, “TxTOHEnable output
pins, and the “TxTOH” and “TxTOHIns” input pins function as
the “Transmit TOH Input Port”.
This output pin will pulse high (for one period of TxTOHClk),
one “TxTOHClk” clock period prior to the first “TOH bit” of a
given STS-3 frame, being expected via the “TxTOH” input pin.
To externally insert user values of TOH into the “outbound”
STS-3 data stream via the “Transmit TOH Input Port”, do the
following.
• Continuously sample the state of “TxTOHEnable” and this
output pin upon the rising edge of “TxTOHClk”.
•
then the user’s external circuitry should drive the “TxTOHIns”
input pin “HIGH”.
• Next, the user should output the next TOH bit, onto the
“TxTOH” input pin, upon the rising edge of “TxTOHClk”.
Note:
23
Whenever the “TxTOHEnable” output pin pulse “HIGH”,
Continuously sample the state of “TxTOHFrame” and
Data at this input pin will be ignored (e.g., not
sampled) unless the “TxTOHEnable” output pin is
“HIGH” and the “TxTOHIns” input pin is pulled
“HIGH”.
the “Transmit TOH Input Port” can use this particular
output pin to denote the boundary of STS-3 frames.
The external circuitry (which is being interfaced to
XRT94L33
Rev.1.2.0.