Keysight Technologies 3458A Guide D'utilisation page 206

5 Digitizing
Direct sampling remarks
– You cannot use autorange for direct-sampled measurements; you must specify
– The multimeter's triggering hierarchy (trigger arm event, trigger event, and
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the range as the first parameter of the DSAC or DSDC command (max._input
parameter). The max._input parameters and the ranges they select are:
max._input parameter
0 to .012
>.012 to .120
>.120 to 1.2
>1.2 to 12
>12 to 120
>120 to 1E3
Notice that when using the DINT memory/output format, the full scale values
for direct-sampling are 500% (5 times) the ranges of 10 mV, 100 mV, 1 V, 10 V,
and 100 V. This is particularly important to consider when specifying the
percentage for level triggering. When specifying the level triggering voltage,
use a percentage of the range. For example, assume the input signal has a
peak value of 20 V and you are using the 10 V range. If you want to level
trigger at 15 V specify a level triggering percentage of 150% (LEVEL 150
command). (The slew rate of the multimeter's amplifiers may be exceeded
when measuring a signal with a frequency >2 MHz and an amplitude >120% of
range; signals ≤120% of range with frequencies up to 12 MHz do not cause
slew rate errors.)
sample event) applies to direct-sampling. This means that these events must
occur in the proper order before direct sampling begins. Refer to
more information on the triggering hierarchy. For direct sampling, you can use
either the TIMER sample event and the NRDGS n,TIMER command; or the
SWEEP command (SWEEP is the simpler to program). The NRDGS and
SWEEP commands are interchangeable; the multimeter uses whichever
command was specified last. (When using the SWEEP command, the sample
event is automatically set to TIMER.)
Selects range
10 mV
100 mV
1 V
10 V
100 V
1000 V
Full scale
SINT format DINT format
12 mV
120 mV
1.2 V
12 V
120 V
1050 V
Keysight 3458A User's Guide
50 mv
500 mV
5.0 V
50 V
500 V
1050 V
Chapter 4 for