diode applications Flashcards
Which diode(s) has (have) a zero level current and voltage drop in the ideal model?
A) Si
B) Ge
C) Both Si and Ge
D) Neither Si nor Ge
C) Both Si and Ge
In a voltage regulator network with fixed RL and R, what element dictates the minimum level of source voltage?
A) VZ
B) IZ
C) IZM
D) None of the above
A) VZ
A Zener diode is in a _______ impedance region in the forward bias while it has a _______ impedance region in the reverse bias.
A) very large, low
B) very large, very large
C) low, low
D) low, very large
D) low, very large
The load line is defined by the _______ and a characteristic curve is defined by the _______.
A) quiescent point, device
B) device, network
C) network, device
D) None of the above
C) network, device
The PIV rating of the diodes in a full-wave rectifier must be larger than _______ Vm.
A) 0.318
B) 0.636
C) 2
D) 1
D) 1
Rectifiers are commonly used in battery chargers.
A) True
B) False
A) True
The slope of the load line depends on the _______.
A) type of the diode used
B) characteristic curve
C) load resistor
D) source voltage
C) load resistor
The combination of a short circuit in series with an open circuit always results in a(n) _______ circuit.
A) open
B) short
C) neither short nor open
D) unknown
A) open
The source voltage must be _______ the voltage drop across the diode to conduct the diode.
A) larger than
B) smaller than
C) the same as
D) None of the above
A) larger than
What is the peak inverse voltage across each diode in a voltage doubler?
A) Vm
B) 2 Vm
C) 0.5 Vm
D) 0.25 Vm
B) 2 Vm
List the categories of clippers.
A) Series
B) Parallel
C) Series and parallel
D) None of the above
C) Series and parallel
An open circuit can have any voltage across its terminals, but the current is always ________.
A) 5 A
B) 0 A
C) 1 A
D) ∞
B) 0 A
A diode is in the “_____” state if the current established by the applied sources is such that its direction matches that of the arrow in the diode symbol, and VD ≥ 0.7 V for Si and VD ≥ 0.3 V for Ge.
A) off
B) on
C) neutral
D) quiescent
B) on
The x-intercept of the load line with the characteristic curve is determined by the _______.
A) load resistor
B) diode
C) source voltage and the load resistor
D) source voltage
D) source voltage
For the “off” state of a Zener diode, the voltage across the diode should be _______.
A) greater than VZ
B) zero
C) less than VZ but greater than zero
D) None of the above
C) less than VZ but greater than zero
As the load resistor increases, the slope of the dc load line and the levels of diode current ______.
A) increase
B) decrease
C) remain unchanged
D) are unpredictable
B) decrease
A germanium diode is approximated by _______ equivalent for voltages less than 0.3 V.
A) a short circuit
B) a series circuit
C) a parallel circuit
D) an open circuit
D) an open circuit
The dc voltage level of a silicon diode is _______ its ideal model.
A) smaller than
B) larger than
C) the same as
D) None of the above
B) larger than
The full-wave voltage doubler provides _______ filtering action than (as) the half-wave voltage doubler.
A) better
B) poorer
C) the same
D) None of the above
A) better
For the ideal diode the transition between states will occur at the point on the characteristic curve when VD = _______ V and ID = _______ A.
A) 0.3, 0
B) 0, 0
C) 0.7, 0
D) 0.7, 0.3
B) 0, 0
The quiescent point (Q-point) is defined by a(n) _______.
A) ac network
B) dc network
C) ac and dc network
D) None of the above
B) dc network
Determine the total discharge time for the capacitor in a clamper having C = 0.01 µF and R = 500 kΩ.
A) 5 ms
B) 25 ms
C) 2.5 ms
D) 50 ms
B) 25 ms
The absence of the Si or Ge and VD label on a diode denotes _______ notation.
A) approximate model
B) ideal model
C) exact model
D) None of the above
B) ideal model
A short circuit has a _____ drop across its terminals, and the current is limited only by the surrounding network.
A) 5 V
B) 0 V
C) 1 V
D) ∞
B) 0 V
Zener diodes are used in regulator networks to _______.
A) generate voltage
B) consume power
C) maintain a fixed voltage across the load resistor
D) protect the load
C) maintain a fixed voltage across the load resistor
The ratio of the total swing of the output of a clamper to its input total swing is _______.
A) 1
B) 2
C) 0.5
D) 0
A) 1
With the Zener diode in the “on” state, increasing IL will _____ IZ and _____IR.
A) decrease, increase
B) increase, decrease
C) decrease, keep the same level of
D) increase, keep the same level of
C) decrease, keep the same level of
Once the Zener diode is in the “on” state, VZ is always _______ VL.
A) larger than
B) smaller than
C) the same as
D) None of the above
C) the same as
