Operation Theory
45
Figure 21 shows a typical D/A timing diagram. D/A updates its out-
put on each rising edge of DAWR. The meaning of the counters
above is dis-cussed more in the following sections.
Figure 4-14: Typical D/A timing of waveform generation (Assuming the data
in the data buffer are 2V, 4V, -4V, 0V)
Note
:
The maximum D/A update rate is 1MHz. Therefore, the min-
imum setting of the UI_counter is 40 while using an internal
TIMEBASE(40MHz).
Trigger Modes
Post-Trigger Generation
Use post trigger when you want to perform DA waveform right
after a trigger event occurs. In this trigger mode DLY1_Counter is
not used and you don’t need to specify it. Figure 4-15 shows a sin-
gle waveform generated right after a trigger signal is detected. The
trigger signal could come from a software command, an analog
trigger or a digital trigger. Please refer to section 4.5 for detailed
information.
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