Model 2651A High Power System SourceMeter® Instrument Reference Manual
Section 3: Functions and features
2651A-901-01 Rev. A / March 2011
3-3
Filters
The filter feature lets you set the filter response to stabilize noisy measurements. The Model 2651A
uses a digital filter, which is based on reading conversions. The displayed, stored, or transmitted
reading is calculated using one or more reading conversions (from 1 to 100).
Filter types
The Model 2651A has three filter types. These three filter types are broken down into two averaging
filters and one median filter.
The two averaging filters are repeating and moving (see figure below). For the repeat filter (which is
the power-on default), the stack (filter count) is filled, and the conversions are averaged to yield a
reading. The stack is then cleared, and the process starts over.
Figure 32: Moving average and repeating filters
Conversion
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A. Type: Moving average, readings = 10
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B. Type: Repeating, readings = 10
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