LMH0346SQ NSC [National Semiconductor], LMH0346SQ Datasheet - Page 11

• Manufacturer Part Number: LMH0346SQ
• Description: 3 Gbps HD/SD SDI Reclocker with Dual Differential Outputs
• Manufacturer: NSC [National Semiconductor]

SCO_EN
Input SCO_EN enables the SCO/SDO2 differential output to
function either as a serial clock or second serial data output.
SCO/SDO2 functions as a serial clock when SCO_EN is high.
This pin has an internal pull-down device. The default state
(low) enables the SCO/SDO2 output as a second serial data
output.
CRYSTAL OR EXTERNAL CLOCK REFERENCE
The LMH0346 uses a 27 MHz crystal or external clock signal
as a timing reference input. A 27 MHz parallel resonant crystal
and load network may be connected to the XTAL IN/EXT CLK
and XTAL OUT pins. Alternatively, a 27 MHz LVCMOS com-
patible clock signal may be input to XTAL IN/EXT CLK. Pa-
rameters for a suitable crystal are given in
Table
3.
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Frequency
Frequency Stability
Operating Mode
Load Capacitance
Shunt Capacitance
Series Resistance
Recommended Drive Level
Maximum Drive Level
Operating Temperature Range
Parameter
TABLE 3. Crystal Parameters
27 MHz
±50 ppm @
recommended drive level
Fundamental mode,
Parallel Resonant
18–20 pF
7 pF
40Ω max.
100 µW
500 µW
−10°C to +60°C
Value
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