3 - Programming the DC Source
When a measurement is initiated, the dc source continuously samples either the instantaneous output voltage or current. As shown in figure
OFFSET = |
|
4096 DATA POINTS |
|
OFFSET = |
|
4096 DATA POINTS |
|
OFFSET = 0 |
|
4096 DATA POINTS |
|
OFFSET = 0 to 2 9 | 4096 DATA POINTS |
TIME |
|
ACQUISITION |
|
TRIGGER |
|
Figure 3-6. Pre-event and Post-event Triggering
To offset the beginning of the acquisition buffer relative to the acquisition trigger, use:
SENSe:SWEep:OFFSet:POINts <offset>
The range for the offset is
Pulse Measurement Example (Agilent 66312A, 66332A only)
The following program illustrates how to make a pulse measurement over the GPIB. The measurement function is set to ACDC, which gives the best results for current waveforms that have ac content. The measurement incorporates 100 readings taken at time intervals of 20 microseconds, for a total measurement time of 2 milliseconds. The trigger point for the pulse measurement occurs at 0.1 amperes on the positive slope of the current pulse. The measurement offset is programmed so that 20 measurement points prior to the trigger are also returned as part of the measurement sample.
Because measurement triggers are initiated by the current pulse, a FETCh command is used to return the measurement data. FETCh commands are also used to return the MAXimum, MINimum, HIGH, and LOW values of the measurement.
NOTE: MEASure commands cannot be used to return data in this example because they always acquire NEW measurement data each time they are used.
The program can be run on any controller operating under Agilent BASIC. To generate output pulses, an electronic load is programmed to generate
30