Keithley 7017, Instruction Manual

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Operation
3-7
3.6.2 Filter testing
Filter frequency response and phase characteristics are key
circuit parameters that often require testing. The Model 7017
may be used in conjunction with a network analyzer to test
multiple filters on an automated basis.
Figure 3-4 shows a typical circuit configuration for testing
four filters. Note that the network analyzer input is connected
to the output of one Model 7017 multiplexer. One terminal
of each DUT is connected to a corresponding Model 7017
channel, while the remaining DUT terminals are connected
in common to the network analyzer output port.
The basic configuration shown in Figure 3-4 may also be
used for a variety of other tests. For example, the same gen-
eral scheme may be used to test amplifier S-parameters.
3.6.3 Tape head production testing
The Model 7017 can be used with an LCR bridge to produc-
tion test tape heads. Such testing generally involves measuring
device impedance variations to help control manufacturing
processes.
IN 1
IN 2
OUT A
IN 3
IN 4
IN 5
IN 6
Model 7017
OUT B
IN 7
IN 8
Network Analyzer
IN (PORT 1) OUT (PORT 2)
Filter 1
Filter 2
Filter 3
Filter 4
Figure 3-4
Filter testing
Figure 3-5 shows the general circuit configuration for pro-
duction testing using the Model 7017 along with a suitable
LCR bridge. Since 4-wire connections are required for such
measurements, a minimum of two Model 7017 cards are
necessary for this application. Each multiplexer switches
one of the four required signal paths to the DUTs, and each
pair of cards can test a maximum of four devices. Additional
cards can be added as described in paragraph 3.6.1 to ex-
pand device test capabilities by adding more multiplexer
channels.
Key parameters and advantages for using the Model 7017 for
these production tests are:
• Small-signal, high-frequency AC switching: 20mV,
100
µ
A @ 10MHz.
• Long relay life: >10
8
closures.
• High repeatability with little resistance variation be-
tween closures: < 10m
Ω
.