XRT94L31IB Exar Corporation, XRT94L31IB Datasheet - Page 11

• 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

REV. 1.0.1
PIN DESCRIPTION OF THE XRT94L31 (REV. B)
PIN #
P1
SIGNAL NAME
REFTTL
I/O
I
TTL
TYPE
19.44MHz or 77.76MHz Clock Synthesizer Reference Clock Input
Pin:
The function of this input pin depends upon whether or not the Clock
Synthesizer block is enabled.
If Clock Synthesizer is Enabled.
If the Clock Synthesizer block is enabled, then it will be used to generate
the 155.52MHz, 19.44MHz and/or 77.76MHz clock signal for the Trans-
mit STS-3/STM-1 circuitry. In this mode, the user should apply a clock
signal of any of the following frequencies to this input pin.
•
•
•
•
Afterwards, the user needs to write the appropriate data into the Trans-
mit Line Interface Control Register (Address Location = 0x0383) in order
to (1) configure the Clock Synthesizer Block to accept any of the above-
mentioned signals and generate a 155.52MHz, 19.44MHz or 77.76MHz
clock signal, (2) to configure the Clock Synthesizer to function as the
Clock Source for the STS-3/STM-1 block.
If Clock Synthesizer is NOT Enabled:
If the Clock Synthesizer block is NOT enabled, then it will NOT be used
to generate the 19.44MHz and/or 77.76MHz clock signal, for the STS-3/
STM-1 block. In this configuration seting, the user MUST apply a
19.44MHz clock signal to this input pin.
N
OTE
19.44 MHz
38.88 MHz
51.84 MHz
77.76 MHz
: The user must place a clock signal to this input pin in order to
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC
perform READ and WRITE operations to much of the SONET/
SDH-related registers via the Microprocessor Interface.
11
DESCRIPTION
XRT94L31