22
TIMEBASE
DATA
D1
D253 D254
Acquisition
In Progress
Trigger
Acquisition starts right after this clock edge
D2
5
5
2
D
4
D
3
D
D256
Analog
signal
Trigger mode = post-trigger, DataCnt = 256, ScanIntrv = 1
Figure 3-4: Basic Acquisition Timing Of Digitizer
3.2.3 AI Data Format
The following table illustrates the idea transfer characteristics of various input ranges of the
PCI/PXI-69816/26/46. The data format of the PCI/PXI-69816/26/46 is straight binary.
Description
Analog Input Range
Digital Code (HEX)
Full-scale Range
±1 V
±0.2 V
Least significant bit 30.52 μV
6.10 μV
FSR – 1LSB
0.999969 V
0.199993 V
FFFF
Mi 1LSB
30.5 μV
6.10 μV
8001
Midscale
0.0 V
0.0 V
8000
Midscale - 1LSB
-30.5 μV
-6.10 μV
7FFF
-FSR
-1.000 V
-0.200 V
0000
Table 3-2: AI Data Format
