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Flashcards in D6 DIODES Deck (45)
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1

The diode is a (linear/non-linear) device:

non-linear

2

A diode in reverse breakdown can be used as a

voltage regulator or voltage reference

3

As long as a Zener diode is in reverse breakdown, an approximately ____ voltage called ____ will be found across a parallel load

constant, Vz

4

If the current through a Zener diode in breakdown is less than zero, then

the diode no longer controls the voltage across itself and therefore, any parallel loads

5

True/False: The Zener diode has a non-zero Zener resistance, Rz

True

6

In a pn junction diode, the point where the semiconductor material changes from p to n type is called the

metallurgical junction

7

The pn junction diode is constructed using the impurity process called _____

doping

8

The p-type region of a diode is also called the

anode (the arrow) +

9

The n-type region of a diode is also called the

cathode (the line) -

10

In a Conventional diode the + charge moves

the + charge moves in the direction opposite to current (electron flow)

11

which is positive anode or cathode

the cathode attracts + charge. The anode attracts negative charge.

12

Zener diodes are designed to operate in

reverse = Zener voltage otherwise in forward bias they drop only 0.7 volts

13

Which transistor has the arrow of the emitter poiNting towards the base (PNP/NPN)

PNP

14

How can one spot is the Bias is forward or reversed?

Negative to Positive is forwards
Positive to Positive is reversed
Compare to battery and resistors in circuit

15

What makes silicon more desirable to use than germanium?

Silicon has more resistance to heat than germanium.

16

What happens with a negative temperature coefficient?

Negative temperature coefficient means increase temperature=decrease in resistance.

17

What are the two semiconductor elements suitable for electronic applications?

Silicon (Si) 0.7 VD
and Germanium (Ge) 0.3 VD

18

Crystal lattice structure is part of what?

Covalent bonding where 8 electrons are shared = a stable 8 electron arrangement

19

Pentavalent is what type of impurity

N-type, pure semiconductor crystal with 5 electrons, CATHODE

20

Trivalent is what type of impurity

P- type with 3 electrons and a semiconductor crystal, ANODE

21

As temperature of a material increases it electrical resistance decreases

Negative Temperature Coefficient

22

Silicon has__________resistance than germanium at room temperature

1000 times more

23

Semiconductor materials .

Have characteristics that fall between insulators and conductors

24

When using semiconductors, what is the major problem that must be controlled?

Heat and the changes caused by heat.

25

Holes constantly drift towards

drift towards the NEGATIVE terminal of the voltage source.

26

Electrons always flow

towards the POSITIVE terminal of the voltage source

27

What are 2 pentavalent impurities?

Arsenic & Antimony

28

What are 2 trivalent impurites?

Indium & Gallium

29

Electrons in the outer band or shell of an element are characterized by their:

Energy

30

The conductivity of P-type and N-type semiconductor materials depends on:

the doping level.