
Application Notes
AN1006
2002 Teccor Electronics
Thyristor Product Catalog
AN1006 - 9
http://www.teccor.com
+1 972-580-7777
3. Set 
Max Peak Volts
 to 
75 V
. (
80 V
 on 370)
4. Set 
Mode
 to
 DC
.
5. Set 
Horizontal
 knob to
 Step Generator
.
6. Set 
Vertical
 knob to approximately 10% of the maximum I
H
specified.
Note: Due to large variation of holding current values, the
scale may have to be adjusted to observe holding current.
7. Set 
Number of Steps
 to 
1
.
8. Set 
Step/Offset Polarity
 to non-inverted (button extended, 
on 577 button depressed).
9. Set 
Offset
 by depressing
 0 
(zero). (Press 
Aid
 and O
ppose
 at 
same time on 370.)
10. Set 
Terminal Selector
 to 
Step Generator-Emitter Grounded.
Procedure 8: I
H(Forward)
To measure the I
H (Forward)
 parameter:
1. Set
Polarity
 to (+).
2. Set
Left-Right Terminal Jack Selector
 to correspond with 
location of test fixture.
3. Increase 
Variable Collector Supply Voltage
 to maximum 
position (
100
).
4. Set 
Step Family
 by depressing
 Single.
This could possibly cause the dot on the CRT to disappear,
depending on the vertical scale selected).
5. Decrease 
Variable Collector Supply Voltage
 to the point 
where the line on the CRT changes to a dot. The position of 
the beginning point of the line, just before the line becomes a 
dot, represents the holding current value. 
(Figure AN1006.13)
Figure AN1006.13 I
H (Forward)
 = 8.2 mA
Procedure 9: I
H(Reverse)
To measure the I
H (Reverse)
 parameter:
1. Set 
Polarity
 to (–).
2. Repeat Procedure 7 measuring I
H(Reverse)
. (Read measure-
ments from upper right corner of the screen.)
Procedure 10: I
GT
To measure the I
GT
 parameter:
1. Set 
Polarity
 to (+).
2. Set
Number of Steps
 to 
1
. (Set number of steps to 
0 
(zero) 
on 370.)
3. Set 
Offset
 by depressing 
Aid
. (On 577, also set 
Zero
 button 
to 
Offset
. Button is extended.) 
4. Set
Offset Multiplier
 to 
0
 (zero). (Press 
Aid
 and 
Oppose
 at 
same time on 370.)
5. Set 
Terminal Selector
 to 
Step Generator-Emitter Grounded. 
6. Set 
Mode
 to
 Norm.
7. Set 
Max Peak Volts
 to 
15 V
. (
16 V
 on 370)
8. Set
Power Dissipation
 to 
10 W
.
9. Set
Step Family
 by depressing
 Single
.
10. Set
Horizontal
 knob to 
2 V/DIV
.
11. Set 
Vertical
 knob to 
50 mA/DIV
.
12. Set 
Step/Offset Polarity
 to non-inverted position (button 
extended, on 577 button depressed).
13. Set 
Variable Collector Supply Voltage
 until voltage 
reaches 12 V on CRT.
14. After 12 V setting is completed, change 
Horizontal
 knob to
Step Generator
.
Procedure 11: I
GT
 – Quadrant I [MT2 (+) Gate (+)]
To measure the I
GT
 – Quadrant I parameter:
1. Set 
Step/Offset Amplitude
 to approximately 10% of rated 
I
GT
.
2. Set 
Left-Right Terminal Jack Selector
 to correspond with 
location of test fixture.
3. Gradually increase 
Offset Multiplier
 until device reaches 
conduction point. (Figure AN1006.14) Measure I
GT
 by follow-
ing horizontal axis to the point where the vertical line passes 
through the axis. This measured value is I
GT
. (On 370, I
GT
 is 
numerically displayed on screen under offset value.)
Figure AN1006.14 I
GT
 in Quadrant I = 18.8 mA
5
mA
100m
PER
V
E
R
T
DIV
PER
H
O
R
I
Z
DIV
PER
S
T
E
P
()k
DIV
9m
PER
DIV
50
mA
IH
50
mA
10
PER
V
E
R
T
DIV
PER
H
O
R
I
Z
DIV
PER
S
T
E
P
()k
DIV
9m
PER
DIV
5
mA
IGT