Chapter 3 Flashcards
1
Q
Thyristors are primarily used as ______ devices
A
Switching
2
Q
When holding current drops below it’s minimum value, the thyristors will
A
Turn off
3
Q
The term “trigger” refers to turning _____ a thyristor device
A
On
4
Q
The SCR has _____ semiconductor layers and _____ junctions
A
4 and 3
5
Q
The trigger time for a SCR with a capacitor at its gate ranges from
A
0 to 180 degrees
6
Q
The SCR is triggered by a _______ voltage applied to its gate
A
Positive
7
Q
The gate lead of an SCR is used to turn it
A
On
8
Q
A ______ voltage can be applied across an SCR
A
Both a and b (AC and D.C.)
9
Q
Once the SCR is triggered on, it can be turned off in a D.C. circuit when a
A
Holding current falls below the minimum point
10
Q
The ______ is a bidirectional device
A
Diac
