AA Revision 2

What happens to the output of a comparator if the inverting input (−) is connected to a reference voltage of 2V and the non-inverting input (+) is at 1V?

• A) The output will be at the positive saturation voltage.
  

• B) The output will be at the negative saturation voltage.
  

• C) The output will be at zero volts.
  

• D) The output will be the same as the non-inverting input voltage.

The load line in a transistor circuit represents:

• A) The voltage-current relationship for the transistor itself.
  

• B) The maximum current the transistor can handle.
  

• C) The relationship between the collector current and collector-emitter voltage for a given load resistor.
  

• D) The power dissipation curve of the transistor.

Which one of the following is an example of the non-linear Op-amp application?

• Adder.

• Comparator.

• Inverting amplifier.

• Difference amplifier.

 Fig 3 shows an Op-amp circuit. Determine the voltage obtained at Vo.

• -15 V.

• -11.8 V

• 11.8 V

• 15 V.

Fig 2 shows a non-inverting Op-amp circuit. Calculate the volage gain, Av.

• -1

• -2

• 1

• 2

Fig 1 shows a basic switching regulator. If the output voltage tends to decrease due to an increase in the load, the conduction time of the switch transistor Q1 is

• longer.

• irregular.

• shorter.

• unchanged.

In a simple shunt regulator, a current controlled element is connected in parallel with the load. Identify the current controlled element

• Resistor.

• Capacitor.

• Transistor.

• Zener diode.

The capacitor filter in a power supply circuit is used to

• amplify the ac ripple voltage.

• reduce the ac ripple voltage.

• produce the ac ripple voltage.

• maintain the ac ripple voltage.

Determine which component of Fig 3 compensates for fluctuations in the output voltage.

• 
  

  Q1.

• Q2.

• R4.

• Z.

A voltage regulator has an open circuit output voltage of 30 V. When a load is connected across the output terminals, the load voltage drops to 29 V. Calculate the percentage voltage regulation.

• -3.33 %.

• 0 %.

• 3.33 %.

• 3.45 %.