Section 3: Functions and features
Series 2600B System SourceMeter® Instrument Reference Manual
3-26
2600BS-901-01 Rev. C / August 2016
In this example:
A
= 0,
V
start
= 1,
V
end
= 10,
N
= 5
Using the formula above,
k
= 1
Step size (
b
) for the sweep in the above figure is calculated as follows:
Figure 57: Logarithmic staircase sweeps (2)
Log Step Size
log10(stop-0) log10(start-0)
–
Points 1
–
-----------------------------------------------------------------------------
=
log10(10) log10(1)
–
5 1
–
-----------------------------------------------------
=
1 0
–
(
)
4
-----------------
=
0.25
=
Therefore,
b = 10
(log step size)
= 1.7783
The five log steps for this sweep are listed in the Logarithmic sweep points table below.
Logarithmic sweep points
Source point
(N)
Source level
(V)
Step number
(i)
1
1
0
2
1.7783
1
3
3.1623
2
4
5.6234
3
5
10
4
When this sweep starts, the output will go to the start level (1 V) and sweep through the symmetrical
log points.
To configure a logarithmic staircase sweep, use the
smu
X
.trigger.source.log
Y
()
function. This
function configures the source values the source-measure unit (SMU) will output when performing a
logarithmic sweep. After configuring the sweep, you must also enable the source action by setting the
following attribute:
smu
X
.trigger.source.action
