PPT #3/4 Notes Flashcards
The _______ section of a power supply removes ripple, flattening the pulsating DC to make a more consistent load line.
filter
Filter circuit stores _______ when current is high and releases when _____
energy
low
A power source filter is combination of? (3)
Capacitors
Inductors
Resistors
Capacitor stores _______
Inductor stores _______-_______
Resistor is a voltage _______ device
voltage
magnetic-field
dropping
As pulsating voltage from the rectifier is applied to the capacitor, it charges to the _____ voltage applied
peak
The capacitive filter is connected in ________ with the load device
parallel
Between peaks, the capacitor discharges through the load and _____ gradually drop
volts
What is the amount of voltage drop before the capacitor begins to charge again called? It never goes to zero volts
Ripple voltage
RC stands for?
Recharge time
Adv and Disadv of capacitive filters?
low cost and low ripple at low load
high ripple at high load
Over time, surge currents may damage circuit fuses and diodes. True or false?
True
Purpose of and L section resistive filter?
Reduces surge currents
How does an L-section resistive filter reduce surge currents?
with a current limiting resistor that uses an RC time constant to slow charging of capacitor
Resistor should always be connected in _____ with the rectifier
series
Resistor connected in series with the rectifier serves what purpose?
protects it from high surge charging currents
The surge reducing device is known as a ?
current limiting inductor (coil)
On which principle does a current limiting inductor work?
counter electromotive force (CEFM) or counter voltage to oppose current
Two types of pi-section filters are?
Inductive and resistive
Which filters are more effective, Inductive or Resistive?
Inductive
The requirements of the _____ determine if voltage regulation is required
load
The voltage regulator is variable resistance that automatically changes as the output voltage changes. True or False?
True
Load current flows through a variable resistor and creates a ______ _____ across
voltage drop
The variable resistor and the load create a ___ voltage divider
DC
Resistance to maintain constant voltage drop can be adjusted even when input variations occur. True or False?
True
To maintain voltage drop across the load. The resistance can be _________
reduced
The limitation of a variable resistor circuit is?
it must be operated manually
A _______ is a variable resistor in parallel
shunt
A shunt regulator combined with the resistance of the power supply itself,
or with an additional resistor, forms a ______ ________
voltage divider
As shunt resistance increases, more voltage appears across it as an output to the load. True or False?
True
As shunt resistance decreases, voltage across decreases. True or False?
True
The resistance of a shunt regulator increases when the output voltage _________
decreases
A voltage _______ distributes the available voltage into those voltages required by the various loads.
divider
When is a voltage regulator used?
When it is required to provide voltages for loads with different voltage requirements
