Chapter 10 SSD&S vocabulary and review questions

What are the forward voltage drops usually associated with germanium and silicon?

0.2 volts for germanium and 0.6 volts for silicon.

Common-Collector Amplifier

A bipolar junction transistor (BJT) with both the input and output signals connected to the collector.

Common-Base Amplifier

A bipolar-junction transistor with both the input and output signals connected to the base.

Common-Emitter Amplifier

A bipolar-junction transistor with both the input and output signals connected to the emitter.

What is another name for a common-emitter circuit?

A common-emitter circuit is sometimes called a grounded-emitter circuit.

Frequency-Response Curve

A graph that shows a given bandwidth.

Wide Bandwidth

A large range of frequencies over which an amplifier operates.

What is a multistage amplifier?

A multistage amplifier couples together, or connects, various stages of amplification in order to build up the output to the required level.

Cascade Amplifier

A series of connected amplifiers in which the output of one amplifier is connected to the input of another amplifier.

What causes clipping?

A signal may be clipped due to an operating point too close to saturation, an operating point located too close to cutoff, or an input signal that is too large for a normal operating amplifier.

Narrow Bandwidth

A small range of frequencies over which an amplifier operates.

Decibel (dB)

A unit of measure used to express the relative intensity of sound.

What is amplification?

Amplification is the process of taking a small signal and making it larger.

Linear Amplifier

An amplifier that increases and maintains the exact duplicate of an input signal.

What is a linear amplifier?

An amplifier that increases and maintains the exact duplicate of an input signal.

Transistor Tester

An electric device that tests the electrical characteristics of transistors and diodes.

Define distortion.

Any undesirable change in a signal.

Distortion

Any undesirable change in a signal.

Phase Inversion

As the input increases, the output decreases.

What is phase inversion?

As the input increases, the output signal decreases. As the input signal decreases, the output signal increases.

What are the major amplifier coupling techniques?

Capacitive coupling, transformer coupling, and direct coupling.

What are the four main classes of amplifier operation?

Class A amplifier operation, Class A amplifier operation, Class AB amplifier operation, and Class C amplifier operation.

What are the advantages of using Darlington circuits?

Fewer components are required and there is no less incurred in the coupling. The Darlington circuit can be used as an output stage of a transistor amplifier that is driven by a stage of low or intermediate power.

Isolation Amplifier

The common collector circuit is often used as an isolation amplifier because of its high input impedance.

Where are common-collector circuits used?

The common-collector circuit is used widely in applications where its high input resistance and low output resistance can perform useful functions. The circuit is often used to couple high-impedance loads.

Explain the difference between amplifier current gain and beta (B).

The current gain for an amplifier is not the same as the current gain for an individual transistor, which is shown as beta (β). Beta refers to the transistor as a single device. It does not refer to the entire amplifier circuit containing the transistor. The amplifier gain for a particular transistor circuit should always be less than the β of the single transistor in the circuit.

Define input impedance.

The loading effect an amplifier presents to an incoming signal.

Input Impedance

The loading effect an amplifier presents to an incoming signal.

Define output impedance.

The loading effect an amplifier presents to another device.

Output Impedance

The loading effect an amplifier presents to another device.

Half-Power Point

The point on a frequency-response curve where the power output is one-half the maximum value.

Impedance Matching

The process of setting the input impedance of a load equal to the output impedance of a signal source.

Bandwidth

The range of frequencies over which the gain of an amplifier is maximum and relatively constant.

Define bandwidth.

The range of frequencies over which the gain of an amplifier is maximum and relatively constant.

Current Gain

The ratio of output current to input current.

Power Gain

The ratio of output power to input power.

Voltage Gain

The ratio of output voltage to input voltage.

Gain

The ratio of the amplitude of an output signal to the amplitude of an input signal.

What is gain?

The ratio of the amplitude of an output signal to the amplitude of an output signal to the amplitude of an input signal.

Alpha (a)

The ratio of the change in collector current (IC) to the change in emitter current (IE) with a constant collector voltage.

Describe the three basic types of transistor amplifiers.

The three basic types of transistor amplifiers are the common-emitter, common-base, and common-collector transistor amplifier.

What is another name for a Class A amplifier?

They are also called linear amplifiers.

What is a decibel?

Unit of measure used to express the relative intensity of sound.

Class C Operation

is located closest to cutoff point.

Class B Operation

is located near the lower end of the load line closer to cutoff.

Class AB Operation

is somewhere between Class A and Class B amplifiers on the load line.

Class A Operation

is well above the cutoff condition for an amplifier.

Single-Stage Amplifier

only has one transistor.