NI USB-9229/9239 User Guide and Specifications 14 ni.com
Specifications
The following specifications are typical for the range 0 to 60 °C
unless otherwise noted. All voltages are relative to the AI– signal on each
channel unless otherwise noted.

Input Characteristics

Number of channels................................4 analog input channels
ADC resolution.......................................24 bits
Type of ADC..........................................Delta-Sigma (with analog
prefiltering)
Sampling mode.......................................Simultaneous
Data rate range (fs)
Minimum.........................................1.613 kS/s
Maximum........................................50 kS/s1
Data rates (fs).......................................... , n = 1, 2, ... 31.
Master timebase (internal)
Frequency........................................12.8 MHz
Accuracy..........................................±100 ppm max
Operating voltage ranges2
Overvoltage protection...........................±100 V
Input coupling.........................................DC
Input impedance (AI+ to AI–)................1 MΩ
1 Full performance requires the use of a USB 2.0 Hi-Speed host controller and USB 2.0 hubs.
2 Refer to the Safety Guidelines section for more information about safe operating voltages.
Measurement Voltage, AI+ to AI–
Nominal (V) Typic al (V ) Minimum (V)
NI USB-9229 ±60 ±62.64 ±61.5
NI USB-9239 ±10 ±10.52 ±10.3
50kS/s
n
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