HP E1313A Manual page 147

Note
Adding Settling Delay
for Specific Channels
146 Understanding the HP E1313/E1413
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we can use a gain of 64 and set the Range Amplifier to the 4 volt range. At
this setting the A/D resolution for one LSB drops to about 122 µvolts and
further reduces or removes any need for additional settling delay. This
improvement is accomplished without any reduction of the overall
measurement resolution.
Filter-amplifier SCPs can provide improvements in low-level signal
measurements that go beyond just settling delay reduction. Amplifying the
input signal at the SCP allows using less gain at the Range Amplifier (higher
range) for the same measurement resolution. Since the Range Amplifier has
to track signal level changes (from the multiplexer) at up to 100 KHz, its
bandwidth must be much higher than the bandwidth of individual
filter-amplifier SCP channels. Using higher SCP gain along with lower
Range Amplifier gain can significantly increase normal-mode noise rejection.
This method adds settling time only to individual problem measurements
rather then to all measurements as the
With the HP E1313/E1413, channels will be scanned in any order you
specify including multiple times, and you can specify which readings to
return and which to discard (see the
in Chapter 5). Using this capability you can set your scan sequence to
measure input channels from lowest level to highest level. This will
minimize channel settling problems. If you plan to continuously execute a
scan list, wrapping around from the last channel to the first channel can
present this high-level signal to low-level signal settling problem. To allow
for additional channel settling time here, you can measure the low-level
channel two or more times, but only return data from the final measurement
of that channel. Figure 4-10 will illustrate this idea.
Of course you do not need to specify the optimum sequence for the scan list
channels. You can simply place repeat channels in your existing scan list
anywhere extra settling delay is needed.
SAMPle:TIMer command does.
ROUTe:SEQuence:DEFine command
Chapter 4