Keithley 6430 User Manual

8-4 Data Store
Average
The average mode displays the mean (average) of all measured readings stored in the buffer.
The following equation is used to calculate mean:
where: y is the average.
X
i
is a stored reading.
n is the number of stored readings.
Standard deviation
This mode displays the standard deviation of buffered readings. The following equation is
used to calculate standard deviation:
where: y is the average.
X
i
is a stored reading.
n is the number of stored readings.
Timestamp format
Buffer readings can be recalled using the absolute timestamp format or the delta format. For
the absolute format, readings are referenced to zero seconds. For the delta format, the times-
tamp indicates the time between the displayed reading and the previous reading.
Perform the following steps to set the timestamp format:
1. While in the normal display mode, press CONFIG and then STORE to display the
timestamp choices.
2. Place the cursor on ABSOLUTE or DELTA and press ENTER.
Timestamp accuracy
Because of internal timing methods, the timestamp value is only approximate. The method
in which the timestamp is implemented limits its use in time-critical applications. If accurate
test timing is crucial, it is recommended that an external timer be used in conjunction with the
SourceMeter.
y
X
i
i 1=
n
∑
n
---------------=
y
X
i
2
i n 1–=
n
∑
1
n
---
X
i
i 1=
n
∑
 
 
 
2
 
 
 
–
n 1–
---------------------------------------------------------------=

Keithley 6430 Specifications

General

Brand	Keithley
Model	6430
Category	Measuring Instruments
Language	English