Section 3: Functions and features
Model 2651A High Power System SourceMeter® Instrument Reference Manual
3-24
2651A-901-01 Rev. A / March 2011
Solving for
k
and
b
provides the following formulas:
( )
log10(V
end
- A) - log10(V
start
- A)
N-1
k = V
start
- A
b = 10
Where:
V
end
= The source value at the end point
V
start
= The source value at the start point
N
= The number of points in the sweep
A
= The asymptote value
NOTE
The number of points in a sweep is one greater than the number of steps in the sweep.
The following figure is an example of a five-point logarithmic sweep from 1 V to 10 V.
Figure 38: Logarithmic staircase sweep (1V to 10V, five steps)
Delay
Delay
Delay
Delay
Stop
(10)
Measure
#1
Measure
#2
Measure
#3
Measure
#5
X = Measurement point
X
X
X
X
Delay
X
Measure
#4
1
10
5.6234
3.1623
1.7783
Log
scale
Start
Log points = 5
Volts
