Electronics #2: Operational Amplifier & Power Amplifier

Which of the following is (are) power amplifiers?

• Class A

• Class B or AB

• Class C or D

• All of the above

A differential amplifier....

• is a part of an Op-amp

• has one input and one output

• has two outputs

• answers (1) and (2)

By how much does the output signal vary for a class AB power amplifier?

• 360°

• 180°

• Between 180° and 360°

• Less than 180°

Which type of power amplifier is biased for operation at less than 180º of the cycle?

• Class A

• Class B or AB

• Class C

• Class D

When a differential amplifier is operated single-ended,..

• the output is grounded

• one input is grounded and signal is applied to the other

• the output is not inverted

• both inputs are connected together

In differential-mode, …………….

• the gain is one

• only one supply voltage is used

• opposite polarity signals are applied to the inputs

• the outputs are of different amplitudes

Which type of amplifier uses pulse (digital) signals in its operation?

• Class A

• Class B or AB

• Class C

• Class D

Which of the power amplifiers has the lowest overall efficiency?

• Class A

• Class B or AB

• Class C

• Class D

Which of the following describe(s) a power amplifier?

• It can handle large power.

• It can handle large current.

• It does not provide much voltage gain.

• All of the above

_______ amplifiers primarily provide sufficient power to an output load to drive a speaker from a few watts to tens of watts.

• Small-signal

• Power

• Large-signal

• None of the above