ATT Actual Exam Questions With Reviewed 100%
Correct Detailed Answers Guaranteed Pass!!
What are 5 parts of a power supply? Input, rectifier, filter, regulator, protection
Which two parts of a power supply are
Regulator and protection
optional?
To convert AC power into smooth DC
What is the purpose of a power supply?
power
What does the input of a power supply
Step up or down the AC input voltage
do?
What does the rectifier do in a power
Changes AC into pulsating DC
supply?
What does the filter do in a power sup-
Changes pulsating DC into smooth DC
ply?
How type of components do filters use? Reactive components
maintains the output voltage at a con-
What does a regulator do in a power
stant level despite changes in load cur-
supply?
rent
What does the protection circuit do in Prevents damage to power supply if load
power supply? becomes faulty, limits or disables output
The half wave rectifier is the same as
Series limiter
what circuit?
Which rectifier is the least efficient using
Half-wave
only half the input?
Which two rectifiers require two input sig-
Full-wave and bridge
nals 180 degrees out of phase?
Which rectifier uses a center tapped
Full wave
transformer?
How is frequency determined for half Output frequency is same as input fre-
wave rectifier? quency
How is frequency determined for full
Output is twice the input frequency
wave rectifier?
How is frequency determined for bridge
Output is twice the input frequency
rectifier?
What is the purpose of series voltage To adjust voltage drop to maintain V out
regulators? at constant level
1/7
, In a series voltage regulator, V out IN- Load current decreases OR DC input in-
CREASES when what happens? creases
In series voltage regulator, V out DE- Load current increases OR DC input de-
CREASES when what happens? creases
If load current decreases or DC input in-
creases, what needs to be done to main- Increase R1 resistance to increase volt-
tain constant level of V out (series volt age drop on R1
regulator)?
If load current increases or DC input
decreases, what needs to be done to Increase R1 resistance to decreases
maintain constant level of V out (series voltage drop on R1
voltage regulator)?
What is the purpose of parallel voltage Adjust current flow to maintain V out at
regulator? constant level
In parallel voltage regulator, V out in- DC input increases or load current de-
creases when what happens? creases
In parallel voltage regulator, V out de- When DC input decreases or load cur-
creases when what happens? rent increases
What makes a zener diode different from Zener diode is designed operate in
junction diode? breakdown
When does zener diode conduct reverse When reverse bias voltage is HIGHER
current? than Vz (diode acts like resistor)
When diode is forward biased, what is
0.7V
the output voltage in shunt regulator?
When reverse biased lower than Vz,
Acts like an open
what happens to zener diode?
If reverse biased lower than Vz, what is
Output is applied voltage
output voltage of shunt regulator?
When reverse biased higher than Vz,
what is the output voltage of shunt reg- Vz
ulator?
Which component changes resistances
to maintain constant V out (zener diode Q1
regulator)?
2/7
Correct Detailed Answers Guaranteed Pass!!
What are 5 parts of a power supply? Input, rectifier, filter, regulator, protection
Which two parts of a power supply are
Regulator and protection
optional?
To convert AC power into smooth DC
What is the purpose of a power supply?
power
What does the input of a power supply
Step up or down the AC input voltage
do?
What does the rectifier do in a power
Changes AC into pulsating DC
supply?
What does the filter do in a power sup-
Changes pulsating DC into smooth DC
ply?
How type of components do filters use? Reactive components
maintains the output voltage at a con-
What does a regulator do in a power
stant level despite changes in load cur-
supply?
rent
What does the protection circuit do in Prevents damage to power supply if load
power supply? becomes faulty, limits or disables output
The half wave rectifier is the same as
Series limiter
what circuit?
Which rectifier is the least efficient using
Half-wave
only half the input?
Which two rectifiers require two input sig-
Full-wave and bridge
nals 180 degrees out of phase?
Which rectifier uses a center tapped
Full wave
transformer?
How is frequency determined for half Output frequency is same as input fre-
wave rectifier? quency
How is frequency determined for full
Output is twice the input frequency
wave rectifier?
How is frequency determined for bridge
Output is twice the input frequency
rectifier?
What is the purpose of series voltage To adjust voltage drop to maintain V out
regulators? at constant level
1/7
, In a series voltage regulator, V out IN- Load current decreases OR DC input in-
CREASES when what happens? creases
In series voltage regulator, V out DE- Load current increases OR DC input de-
CREASES when what happens? creases
If load current decreases or DC input in-
creases, what needs to be done to main- Increase R1 resistance to increase volt-
tain constant level of V out (series volt age drop on R1
regulator)?
If load current increases or DC input
decreases, what needs to be done to Increase R1 resistance to decreases
maintain constant level of V out (series voltage drop on R1
voltage regulator)?
What is the purpose of parallel voltage Adjust current flow to maintain V out at
regulator? constant level
In parallel voltage regulator, V out in- DC input increases or load current de-
creases when what happens? creases
In parallel voltage regulator, V out de- When DC input decreases or load cur-
creases when what happens? rent increases
What makes a zener diode different from Zener diode is designed operate in
junction diode? breakdown
When does zener diode conduct reverse When reverse bias voltage is HIGHER
current? than Vz (diode acts like resistor)
When diode is forward biased, what is
0.7V
the output voltage in shunt regulator?
When reverse biased lower than Vz,
Acts like an open
what happens to zener diode?
If reverse biased lower than Vz, what is
Output is applied voltage
output voltage of shunt regulator?
When reverse biased higher than Vz,
what is the output voltage of shunt reg- Vz
ulator?
Which component changes resistances
to maintain constant V out (zener diode Q1
regulator)?
2/7
