Keithley 6485 - Operation Consideration; Response Time

4-10 Range, Units, Digits, Rate, and Filters Model 6485 Picoammeter Instruction Manual
Figure 4-3
Digital filter types; moving and repeating
Response time
The various filter parameters have the following effects on the time needed to display,
store, or output a filtered reading:
• Filter classification: The time to the first reading is the same for both classifica-
tions, but thereafter, the moving mode yields a faster reading than repeating mode.
Also, advanced has a faster response to changes in the input signal than averaging.
• Number of reading conversions: Speed and noise are tradeoffs.
• Noise window: For the advanced filter, a tradeoff of speed, noise, and response to input
signal changes.
Operation consideration
• The digital filter operation will reset (start over) whenever the zero check operation
is performed or the range is changed.
Conversion
#10
#9
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#1
Conversion
Reading
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Reading
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Conversion
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Conversion
Reading
#11
A. Class - Average, Readings = 10, Type - Moving
Conversion
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Reading
#1
Conversion
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Conversion
Reading
#2
Conversion
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Conversion
Reading
#3
B. Class - Average, Readings = 10, Type - Repeating