Question

Student Assessment 1. The complementary PNP/NPN emitter follower circuit is intended as a: a small signal voltage amplifier 6 high frequency amplifier. C high output impedance amplifier. d current/power amplifier 2. If a complementary PNP/NPN output pair is driven with dual polarity power () supplies then the input and output terminals will be at: a half of the positive supply voltage 6 0V (ground). C half of the negative supply voltage. a +0.6V. The Transfer Characteristic of a complementary PNP/NPN output amplifier will be a linear above +0.6V. b a square-law curve. c linear up and down to saturation. d linear over the full range of voltage. The diodes in the base bias network are to: a compensate for temperature. b set the quiescent current to 100mA C prevent reverse currents. d prevent cross-over distortion. The emitter resistors are included in the circuit for the purpose of: a limiting the output power. b preventing damage to the transistors. C setting the quiescent collector current. d stabilizing the quiescent conditions. Crossover distortion is due to: a the need for the transistor to have 0.6V bias to turn on. b the change from low to middle frequencies. c the change from middle to high frequencies. d errors in the power crossing over into the load.

Answer 1

1)

Option D correct !!

Because complementary emitter follower circuit have low output impedance , so have high output current and so provide high current gain .

2)option B

Ground / 0V

3)option C!!

The transfer characteristics show linear graph upto saturation voltage limits for both positive and negative voltages .

4)option C !!

Diodes prevent reverse current while being in reverse bias to incoming current .

5)option B !!

These resistors are bleeding resistors that dissipate excess current as power loss in them .

6)option D

Crossover distortion occurs when one side of amplifier waveform crossing through load is about to reverse !!