LMH0356_08 Datasheet, PDF (12/16 Pages) National Semiconductor (TI) – 3 Gbps HD/SD SDI Reclocker with 4:1 Input Mux and FR4 EQs

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.
ENABLE
The ENABLE pin is used to enable or disable the LMH0356.
When the device is disabled, the output drivers and most of
the internal circuitry are powered down. The crystal oscillator /
external clock reference circuitry (XTAL IN and XTAL OUT)
remain active regardless of the state of ENABLE, allowing the
27 MHz reference clock signal to be generated and passed
on to additional reclockers. The ENABLE pin is active high
and has an internal pull-up device to enable the LMH0356 by
default.
CRYSTAL OR EXTERNAL CLOCK REFERENCE
The LMH0356 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 4.
TABLE 4. Crystal Parameters
Parameter
Value
Frequency
27 MHz
Frequency Stability
±50 ppm @ recommended
drive level
Operating Mode
Fundamental mode, Parallel
Resonant
Load Capacitance
20 pF
Shunt Capacitance
7 pF
Series Resistance
40Ω max.
Recommended Drive Level 100 µW
Maximum Drive Level
500 µW
Operating Temperature
Range
−10°C to +60°C
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