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11
NI 9229/9239
The NI 9229/9239 analog inp
u
t channels are floating with respect
to earth gro
u
nd and each other. The incoming analog signal on each
channel is conditioned, b
u
ffered, and then sampled by a 24-bit
Delta-Sigma ADC.
Each channel provides an independent signal path and ADC,
enabling yo
u
to sample all fo
u
r channels sim
u
ltaneo
u
sly. Refer to
Fig
u
re 5 for an ill
u
stration of the circ
u
itry for one channel.
Figure 5.
Input Circuitry for One Channel of the NI 9229/9239
NI 9229/9239
AI+
AI–
ADC
Amplifier
Overvoltage
Protection
Prefilter