Characteristics Of Transistors - Keithley 595 Instruction Manual

APQLlcATlONS
5.2.4 IV Characteristics of Transistors
Common Emitter Characteristics: Data for common emit-
ter charactexistics are generally obtained by setting the base
Although the Model 595 is not a general purpose transistor
current (l,) to a known value and measuring the collector
tester, it can be useful in measurematS requiring only low
current (I$ as the collector emitter voltage (V,,) is varied.
currents. Typical transistor N measurements are those
The circuit for this measurement is shown in Figure 5-3.
necessary to plot the common emitter characteristics of a
This process is then repeated for a number of base current
bipolar transistor or the common source characteristics of
settings. Data may be plotted showing characteristics such
a FET. Setups for each of these measurements are descriid
as those in Figure 5-4.
in this section. The same principles apply to other semicon-
ductor N characteristic measurements.
r--------y
MODEL 995
,SHIELD t
,
I
I
-0 INPUT
; /Ic iy
---o GUARD METER
( CURRENT )
I
_______ ---------
I
B$C VCE t
--o GUARD
VOLTAGE
I
0 OUTPUT
SOURCE
6 0 GUARD
I
(WHITE BINDING POST)
I
I
I
I
I
I
L--------J
Figure 5-3. Connections for Bipolar Common-Emitter IV Characteristics
10
7-
6-
1&&A
&I-
4-
Ie-IOnA
3-
2-
O
I I I I
I I I
I I
0 I 2 3 4
VCE ( VkTS 5
7 8 9
IO
Figure 5-4. Typical Bipolar Common-Emitter Characteristics
5-4