44
Chapter 4
User Maintenance
Wear Check
Wear Check
The wear check allows you to obtain an idea about the deterioration of the fixture in order
to ensure that the desired measurement accuracy is obtained. This check comprises “User
Limit Setting”, “Reference Value Acquisition” and “Measuring Impedance Shift”. Using a
desired frequency, the impedance (Rs, Ls) of the fixture itself is measured. It is
recommended to use a frequency that is also used under the conditions where the fixture is
normally used.
Normally, “User Limit Setting” should be conducted under the following circumstances.
•
When the equipment is used for the first time following purchase.
•
When the required measurement accuracy is changed.
Normally, “Reference Value Acquisition” should be conducted under the following
circumstances.
•
When the equipment is used for the first time following purchase.
•
Following replacement of parts.
Normally, “Measuring Impedance Shift” should be conducted under the following
circumstances.
•
Once daily and before fixture compensation is performed.
Example of User Limit Values Setting
It is necessary to decide wear check user limit values suitable for the DUT and the
demanded measurement accuracy. An example follows below.
To measure the inductors L: 10 nH and Q: 10 at a frequency (f) of 100 MHz with a
measurement accuracy degree of 20%;
Using the above conditions, the inductor’s reactance X and resistance R are determined in
the following manner.
From
we understand that when R changes 20% (100 m
Ω
) Q
should be approximately 20%, and when L changes 20% (2 nH), L and Q both change
20%. Accordingly, in order to measure both L and Q with a measurement accuracy of 20%
or less, at least the error of L and R must be less than 2 nH and 120 m
Ω
, respectively.
While remembering that L and R change together and keeping in mind other error factors
than the deterioration of the fixture, the respective values should be set to 25% in this
example, i.e., 500 pH and 30 m
Ω
.
L:
10 nH
Q:
10
Frequency:
100 MHz
Demanded Accuracy:
20% for both L and Q
X
2
π
fL
6
Ω
=
=
R
X Q
⁄
0.6
Ω
=
=
Q
X R
⁄
2
π
fL R
⁄
=
=
Содержание 16196A
Страница 7: ...6...
Страница 12: ...Chapter 1 11 Installation Guide Incoming Inspection 1 Installation Guide Figure 1 1 16196A B C D Contents...
Страница 18: ...17 2 Product Overview 2 Product Overview...
Страница 37: ...36 Chapter3 Operation Connecting and Measuring DUTs...
Страница 38: ...37 4 User Maintenance 4 User Maintenance...
Страница 41: ...40 Chapter4 User Maintenance Overview Figure 4 1 Flowchart of User Maintenance...
Страница 59: ...58 Chapter4 User Maintenance Assembling Check...
Страница 68: ...67 6 Service 6 Service This chapter describes the proper maintenance of the fixture and parts replacement...
Страница 85: ...84 Chapter6 Service Assembling Check...
