Operation
5-12
Common-emitter characteristic tests
Common-emitter characteristics are determined by setting
the base current, I
B
, to specific values. At each I
B
value, the
collector-emitter voltage, V
CE
, is swept across the desired
range at specific intervals, and the collector current, I
C
, is
then measured. When the data results are plotted, the
result is the familiar family of common-emitter curves
(Figure 5-9).
Figure 5-9
Typical common-emitter characteristics
The same test configuration used for current gain tests can
be used for measuring common-emitter characteristics. The
Model 224 is used to set the base current, I
B
, to the desired
values. The Model 230 Voltage Source provides the collec-
tor-emitter voltage, V
CE
, and the Model 2000 DMM mea-
sures the collector current, I
C
.
Testing with matrix-digital I/O cards
The Model 7021 can be added to a matrix switching system
to enhance the test capabilities of that system. The follow-
ing paragraphs discuss an overall multiplexer/matrix
switching system and also briefly outline a typical test that
can be made with such a system.
Multiplexer and matrix card connections
Figure 5-10 shows a typical system using Model 7022 and
7021 cards together. In this instance, the multiplexer-digital
I/O card is configured as dual 1
×
12 and 1
×
18 multiplex-
ers. Note that the rows of the matrix-digital I/O card are
connected to the banks of the multiplexer-digital I/O card
through the analog backplane of the mainframe; no external
wiring is necessary to connect the two cards together.
0
1
2
3
4
5
10
8
4
2
6
V , volts
CE
+80
µ
a
+60
µ
a
+40
µ
a
+20
µ
a
I
= 0
B
ma
c
I
A
B
Rows
7022 Matrix Rows
2
2
2
2
Backplane
Jumpers
7021
Multiplexer
Banks
7001/7002 3-Pole
General Purpose
Backplane
DUTs
(12)
Instruments
2
2
1
2
3
4
Note: The 7021 Bank-to-Bank
jumpers must be removed.
DUTs
(18)
1
12
1
18
5
Figure 5-10
Connecting model 7021 and model 7022 cards together
Artisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com
Summary of Contents for 7021
Page 86: ...Artisan Scientific Quality Instrumentation Guaranteed 888 88 SOURCE www artisan scientific com...
Page 87: ...Artisan Scientific Quality Instrumentation Guaranteed 888 88 SOURCE www artisan scientific com...
Page 88: ...Artisan Scientific Quality Instrumentation Guaranteed 888 88 SOURCE www artisan scientific com...
Page 89: ...Artisan Scientific Quality Instrumentation Guaranteed 888 88 SOURCE www artisan scientific com...
Page 90: ...Artisan Scientific Quality Instrumentation Guaranteed 888 88 SOURCE www artisan scientific com...