ECE315_output_stages

Power amplifiers are needed to

• drive small load resistance

• increase the output resistance

• deliver large current levels

• deliver large voltage swings

Emitter Followers are

• Class B power amplifiers

• Class A power amplifiers

• Class AB power amplifiers

• Class C power amplifiers

Which of the following has the highest theoretical power efficiency?

• Emitter Follower

• Push-Pull Output Stage

• Improved Pull-Pull Output Stage

Replacing the PNP in a push-pull stage with a composite transistor (NPN assisted with a PNP) results in

• lower output resistance

• higher output resistance

• lower input resistance

• higher input resistance

Biasing an improved push-pull output stage requires

• 1 diode

• 2 diodes

• 3 diodes