Chapter 20: PN Junction Diodes
MULTIPLE CHOICE
1. Current flow occurs only if the external voltage is ____ the barrier voltage.
a.
equal to
c.
greater than
b.
less than
d.
not equal to
2. When the current flows from the N-type toward the P-type material, the diode is said to have a ____
bias.
a.
forward
c.
maximum
b.
reverse
d.
minimum
3. When a diode is forward biased, the resistance is ____.
a.
zero
c.
low
b.
high
d.
negative
4. In a diode that is ____ biased, the negative terminal of the external voltage source is connected to the
N material, and the positive terminal is connected to the P material.
a.
reverse
c.
minimum
b.
forward
d.
maximum
5. A PN junction diode is a ____-directional device.
a.
one
c.
three
b.
two
d.
four
6. If the ____ is exceeded, a large reverse current flows, creating excess heat and damaging the diode.
a.
forward voltage drop
c.
reverse voltage
b.
maximum forward current
d.
peak inverse voltage
7. The ____ junction method is the method most in use today.
a.
diffused
c.
grown
b.
alloyed
d.
forward
8. In packages for diodes rated at ____ A or less, the cathode is identified by a black, white or silver band
on the end.
a.
three
c.
eight
b.
six
d.
ten
9. If a diode shows both low forward and low reverse resistance, it is probably ____.
a.
opened
c.
germanium
b.
shorted
d.
silicon
10. If the diode measures both high forward and high reverse resistance, then it is probably ____.
a.
opened
c.
germanium
b.
shorted
d.
silicon
COMPLETION
1. A(n) ____________________ is created by joining N- and P-type materials together
2. The region near the junction where the electrons and holes are depleted is called the
____________________.
3. When a voltage is applied to a diode, it is referred to as a(n) ____________________ voltage.
SHORT ANSWER
1. Describe the alloyed junction method of forming a semiconductor.
2. Describe the diffused junction method of forming a semiconductor.
