National Instruments PXI-6289 User Manual page 74

Chapter 4 Analog Input
Figure 4-19. AI Convert Clock Too Fast For AI Sample Clock; AI Convert Clock Pulses Are
AI Sample Clock
AI Convert Clock
Channel Measured
Figure 4-20. AI Sample Clock and AI Convert Clock Improperly Matched;
AI Sample Clock
AI Convert Clock
Channel Measured
Figure 4-21. AI Sample Clock and AI Convert Clock Properly Matched
AI Sample Clock
AI Convert Clock
Channel Measured
It is also possible to use a single external signal to drive both AI Sample Clock and AI Convert
Clock at the same time. In this mode, each tick of the external clock causes a conversion on the
ADC. Figure 4-22 shows this timing relationship.
Figure 4-22. One External Signal Driving Both Clocks Simultaneously
4-28 | ni.com
0
Sample #1
Leads to Aperiodic Sampling
0 1
Sample #1
0
Sample #1
AI Sample Clock
AI Convert Clock
Channel Measured
Gated Off
1 2 3 0 1 2 3
Sample #2
0 1
2 3
Sample #2
1 2 3 0 1 2 3
Sample #2
0 1 2 3
0 1 2 3
Sample #1 Sample #2 Sample #3
0 1 2 3
Sample #3
2 3
0
Sample #3
0 1 2 3
Sample #3
0 1 ...