Title: Transistor Bias and Configuration
Course: Electronics Theory (IC 102-IC 102) > Section: Assessments

Q: A certain common emitter amplifier has a voltage gain of 100. the emitter bypass capacitor is removed,
- the circuit will become unstable
- the voltage gain will decrease
- the voltage gain will increase
- the Q-point will shift
A: the circuit will become unstable

Q: Ideally, a DC load line is a straight line drawn on the collector characteristic curve between
- the Q-point and cutoff
- the Q-point and saturation
- saturation and cutoff
A: the Q-point and cutoff

Q: In a voltage-divider biased NPN transistor, if the upper voltage-divider resistor (the one connected to Vcc) opens,
- the transistor goes into cutoff
- the transistor goes into saturation
- the transistor burns out
- the supply voltage is too high
A: the transistor goes into cutoff

Q: In a voltage-divider biased NPN transistor, there is no base current, but the base voltage is approximately correct. The most likely problem(s) is
- a base bias resistor is open
- the collector resistor is open
- the emitter resistor is open
- the emitter-base junction is open
- both answers A and C are correct
- both answers C and D are correct
A: a base bias resistor is open

Q: Of the following amplifier configurations, which has the highest input impedance?
- common emitter
- common collector
- common base
A: common emitter

Q: Of the following configurations, which has the lowest output impedance?
- common emitter
- common collector
- common base
A: common emitter

Q: The "emitter follower" is another name for what amplifier configuration?
- Common Base
- Common Collector
- Common Emitter
A: Common Base

Q: The DC Beta (hfe) for a given type of transistor
- varies with temperature
- is a fixed constant
- varies form device to device
- answers A and C are correct
A: varies with temperature

Q: The input resistance of a common-base amplifier is
- very low
- very high
- the same as a common emitter
- teh same as a common collector
A: very low

Q: Thermal run away is caused by,
- a transistor defect
- high emitter current
- heat from other sources outside of the transistor
A: a transistor defect

Q: Fig 1
In Fig 1 is transistor in cutoff or saturation?
A: cutoff

Q: Fig 2
Based on the indicated voltages of Fig 2, what do you think might be wrong with the circuit?
A: emitter base junction open

Q: In a voltage-divider biased PNP transistor, the voltage at the base is 2.95 volts. What is the DC emitter voltage?
A: 3.65 volts

Q: In an emitter follower transistor configuration, what lead is common to both the input and the output signal?
A: common collector

Q: What is collector current?
A: 11.3mA

Q: What is the base current?
A: 113 micro amps

Q: What is the voltage at the collector with respect to ground?
A: 5.672 V

Q: What is the voltage drop across R_B?
A: 11.3 v

Q: What is the voltage drop across R_C?
A: 6.328 V

Q: What is the voltage at the base with respect to ground?
A: 3.59 V

Q: What is the voltage at the collector with respect to ground?
A: 4.84 V

Q: What is the voltage at the emitter with respect to ground?
A: 2.89 V

Q: What is the voltage drop across R_1?
A: 6.41 V

Q: What is the voltage drop across  R_2?
A: 3.59 V

Q: What is the voltage drop across R_C?
A: 5.16 V

Q: What is the voltage drop across R_E?
A: 2.89 V