XRT94L33IB-L Exar Corporation, XRT94L33IB-L Datasheet - Page 324

• 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

XRT94L33
Rev.1.2.0.
Figure 72 A Simple Illustration of the “External Circuit” being interfaced to the “TxPOH Input Port”
Note:
•
“TxPOHEnable_n” pin “low”, then it should enter a “WAIT STATE” (e.g., where it waits for __ periods of
“TxPOHClk_n” to elapse). Afterwards, the external circuit should exit this “WAIT STATE” and then place the
very first bit (e.g., the most significant bit) of the “outbound” K1 byte onto the “TxPOH_n” input pin, upon the
very next falling edge of “TxPOHClk_n”. This data bit will be sampled and latched into the “Transmit STS-3c
POH Processor” block circuitry, upon the very next rising edge of “TxPOHClk_n”.
Note:
• Afterwards, the “external circuit” should serially place the remaining fifteen bits (of the K1 and then K2
bytes) onto the “TxPOH_n” input pin, upon each of the next fifteen falling edges of “TxPOHClk_n”.
• The “external circuit” should then revert back to continuously sampling the states of the “TxPOHEnable_n”
and “TxPOHFrame_n” output pins and repeat the above-mentioned process.
Figure 73 presents an illustration of the “TxPOH Input Interface” waveforms, when the “external circuit” is
writing the K1 and K2 bytes into the “TxPOH Input Port”.
Figure 73 Illustration of the “TxPOH Input Interface” waveforms, when the “External Circuit” is writing
the “K1 and K2 bytes” into the “TxPOH Input Port”
Whenever the “external circuit” samples the “TxPOHFrame_n” output pin “high” and also the
The “TxPOHIns_n” line (in Error! Reference source not found.) is “dashed” because this controlling this signal
This “WAIT STATE” period is necessary because the K1 and K2 are the _ and byte within the TOH.
is not necessary if the user has executed “STEP 2” above.
XRT94L43 Device
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
TxPOHEnable_n
TxPOHFrame_n
TxPOHClk_n
TxPOHIns_n
TxPOH_n
324
TxPOHData_OUT
TxPOHFrame_IN
TxPOHEnable_IN
TxPOH_INSERT
TxPOHClk_IN
External Circuit
xr