Keithley 6220 Reference Manual page 192

6-6 Averaging Filter, Math, and Buffer
The noise window for the two filter types are compared in
using the Filter Window (1%), it also shows a window violation occurring after the
sixth A/D conversion. When the voltage makes the transition from Voltage A to
Voltage B, the window violation causes the "A" A/D conversions to be flushed out
of the stack and replaced with copies of the first "B" A/D conversion.
NOTE
Filter example
Filter Type - Moving
Filter Window = 0.01% of range
Filter Count = 10
Ten readings fill the stack to yield a filtered reading. Assume the next reading
(which is the 11
however, the stack will be loaded with that same reading. Each subsequent valid
reading will then displace one of the loaded readings in the stack. The FILT
annunciator will flash until 10 new readings fill the stack.
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - TestEquipmentDepot.com
The noise window cannot be set from the front panel. It
can only be set using remote programming.
th
) is outside the window. A reading will be processed (displayed);
Return to
Model 6220/6221 Reference Manual
Section 6 topics
Figure 6-2. For the filters