Basic Electronic Theory

When used in a circuit, an LED is generally operated at about

20mA or less

Which of the following makes the best conductor?

Aluminum

Which of the following can be thought of as an AC switch?

Diac

How many diodes are required to form a bridge rectifier?

Four

What is the name given to the areas where P-type materials join N-type materials to form a diode?

Gate junction

The figure above shows the electrical symbol for a(n)______

NPN transistor

What is the average number of valence electrons in a conductor atom?

One or two

What semiconductor material comprises the base of an NPN transistor?

P-type germanium

An SRC is made from adjoining layers of semiconductor material in the________

PNPN arrangement

Which of the following is an excellent conductor but too expensive to use on a larger scale?

Silver

How many diodes are required to convert three-phase AC power to high-efficiency DC power?

Six

High-power transistors are manufactured in which configurations?

Studs and heats sinks

Which statement about transistors is correct?

There are three types of junction field-effect transistors.

A transistor is made bv joining how many lavers of semiconductor material?

Three

Which of the following can be viewed as a diac with a gate terminal added?

Triac

How many diodes are required to form a transformer center-tap full-wave rectifier circuit?

Two

The schematic symbol for an LED is the same as that ofa diode with the addition of a(n)

arrow pointing away from the diode

On a transistor, control voltages are applied to the________

base

A__________________rectifier will produce the smoothest DC output voltage.

bridge

One end of a diode has a beveled end which indicates that it is the

cathode

In the figure above, the lead marked C is the transistor___________

collector

In order to permit the emergence of the maximum number of photons in an LED, the conducting surface___________

connected to the P-type material is much smaller

The applied voltage does not have to exceed the breakage voltage in order for conduction to begin on a(n)__________

diac

The process of giving off light by applying an electrical source of energy is called

electroluminescence

In the figure above, the lead marked A is the transistor__________

emitter

By adding ____________________to semiconductor material, P-type material will be created.

gallium

The two basic types of diodes are the silicon and the___________

germanium

The difference between an SCR and a diode is that an SCR_______

has three terminals

The point at which avalanche break over occurs in a diode is known as the_________

peak inverse voltage

Convert AC power to DC power using_______

rectifier diodes

The difference between an N-channel and a P-channel JFET is_______

the polarity of the voltage

The term solid state refers to_____________

the use of semiconductor material in electronic components

When possible, transistor casings will have some marking to indicate_____

which leads are connected to the emitter, collector, or base

Silicon is widely used as a semiconductor because it

withstands heat