National Instruments SC Express PXIe-4309, User Manual

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© National Instruments | 2-11
PXIe-4309 User Manual
Single Convert Acquisition
The PXIe-4309 takes a single convert per channel and returns that as a sample. Figure 2-9
depicts a single convert acquisition of a single channel.
Figure 2-9. Single Convert Acquisition of a Single Channel
Figure 2-10 depicts a single convert acquisition of two channels on the same ADC. The settling
time increases as the aggregate sample rate decreases to allow for more settling time to reduce
settling and ghosting errors.
Figure 2-10.
Single Convert Acquisition of Two Channels on the Same ADC
Table 2-5 shows the max sampling rate based on the maximum number of channels per ADC.
Table 2-5. Maximum Sample Rate (Hardware-Timed Single Point, On-Demand, and
External Sample Clock)
Maximum Channels per ADC Maximum Sample Rate Aggregate Rate
1 900 kHz 900 kHz
2 180 kHz
360 kHz
3 120 kHz
4 90 kHz
Time
S t a mp
Sa mple
Sa mple
Clock
S
ingle Con
v
er
t per
Sa
mple
Convert
Clock
Convert
CH0 CH0
1 2
CH0 CH0
1 2 3
S ETTLING CH8 S ETTLING CH0 S ETTLING CH8 S ETTLING CH0
1
Time
S t a mp
Sa mple
Convert
Sa mple
Clock
1 2 3
Convert
Clock
M
u
ltiple Ch
a
nnel
s
(2) per ADC
S
ingle Con
v
er
t per
Sa
mple
2
CH0 CH8 CH0 CH8