20
Quick Results Guide
Digits
The SourceMeter can display readings at 3
½
-digit, 4
½
-digit, 5
½
-digit or 6
½
-digit resolu-
tion. In situations where the last digits of the reading are noisy, you can turn those digits off by
decreasing display resolution.
To set display resolution, press the DIGITS key until the desired number of digits are dis-
played. Another way to set display resolution is with the following menu sequence:
Press CONFIG > press DIGITS > select 3.5, 4.5, 5.5, or 6.5.
NOTE
Changing DIGITS does not affect measurement SPEED, but changing measurement
speed does affect DIGITS.
Filter
Filtering is used to stabilize noisy readings. In general, the more filtering that is applied, the
more stable (and accurate) the reading. However, more filtering also means slower speed.
The filtering process consists of filling a stack with the specified number of reading conver-
sions (filter count), and then averaging them to yield a filtered reading. The SourceMeter has
two filter types; moving and repeating.
Repeating filter
The stack is filled with the specified number of reading conversions. The reading conver-
sions are averaged to yield a filtered reading. The stack is then cleared, and the process starts
over. Use this filter for sweeping so readings for other source levels are not averaged with the
present source level.
Moving filter
The first reading conversion is placed in the stack, and is copied to the other stack locations
to fill it. Therefore, the first filtered reading is the same as the first reading conversion. The
stack type is first-in, first-out. Each subsequent conversion replaces one of the copied readings
in the stack, which is then averaged to yield the next filtered reading. Note that as this process
continues, a true average is not yielded until the stack is filled with new reading conversions
(no copies in stack).
Once the stack is filled, each subsequent conversion placed into the stack replaces the oldest
conversion. The stack is re-averaged, yielding a new filtered reading.
