National Instruments NI PXI-665 Series, User Manual

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Appendix A Specifications
CLKOUT Characteristics
Output frequency
From PXI_CLK10 ....................................10 MHz
From OCXO/TCXO .................................10 MHz
From DDS
1 ...............................................1 MHz to 105 MHz
Duty cycle .........................................................40 to 60%
Output impedance .............................................50
Ω , nominal
Output coupling ................................................AC
Amplitude, software configurable to two voltage levels (low and high drive)
Square wave rise/fall time (10 to 90%)
High or low drive......................................0.5 - 2.5 ns
PFI <0..5>
Input Characteristics
Frequency range................................................DC to 105 MHz
Input impedance................................................50
Ω , nominal, or 1 k Ω

±10%,

35 pF, software-selectable
Input coupling ...................................................DC
Voltage level......................................................0 V to 5 V
Absolute maximum input voltage
2
...................±5.25 V, max
1
The lower limit is load dependent because of the AC coupling. This limit is less than 1 MHz for
high-impedance loads.
Open Load Square Wave
Low Drive 2.0 Vp-p, typical
High Drive 5.0 Vp-p, typical
50
Ω

Load Square Wave
Low Drive 1.0 Vp-p, typical
High Drive 2.5 Vp-p, typical
2
Stresses beyond those listed can cause permanent damage to the device. Exposure to absolute maximum
rated conditions for extended periods of time can affect device reliability. Functional operation of the
device outside the conditions indicated in the operational parts of the specifications is not implied.