PPSoC101
1. Select all of the common characteristics of a power converter
a. Voltage regulation
b. Efficiency
c. Noise, Distortion, Power Factor
d. Communications interface
e. Size
2. Select the three power converter topologies
a. Buck
b. Boost
c. Buck-Boost
3. What is the steady-state transfer function for a buck converter?
a. Vo=D*Vi
b. Vo=D/Vi
c. Vo=Vi/(1-D)
d. Vo= -D*Vi/(1-D)
4. What is the steady-state transfer function for a boost converter?
a. Vo=D*Vi
b. Vo= -D*Vi/(1-D)
c. Vo=D*Vi*2
d. Vo=Vi/(1-D)
5. What is the steady-state transfer function for a buck-boost converter?
a. Vo=D*Vi
b. Vo= -D*Vi/(1-D)
c. Vo=D*Vi*2
d. Vo=Vi/(1-D)
6. What parameters are important when considering a power converter?
a. The accuracy of the output voltage
b. The efficiency of power conversion
c. The size + cost of the components used to achieve power conversion
d. The noise at the output of the converter.
e. The converter’s ability to protect itself and the system load from
overvoltages, overcurrents, overtemperatures or any such fault
conditions.
PPSoC110
1. What prevents power converters from reaching 100% efficiency?
a. Nonidealities existing in circuit components
b. The inherent size of the power converter
c. The input voltage
2. What is the reprecaution of staying in an interval (or loop) for too long? (select all
that apply)
a. The greater relative loss are that coincide with that interval
b. Decreased current
c. Increased voltage
d. The transfer function of the system changes
3. What components are responsible for ohmic losses for the converter?
a. DC resistance of the inductor
b. Series resistance of the capacitor
c. Parallel resistance of the capacitor
d. AC impedance of the inductor
4. Which circuit diagram corresponds to a step down converter with the MOSFET
turned on?
IIN
iMOSFET
VPWM
L iL RDCR
VOUT
VIN
+ VL -
IOUT
+
COUT
RLOAD
iDIODE
-
L iL RDCR
VOUT
+ VL -
RD IOUT
COUT +
RLOAD
VD
-
a.
b.
IIN
RON iMOSFET
L iL RDCR
VOUT
VIN
+ VL - IOUT
COUT +
RLOAD
-
5. Which component attributes the most to power loss efficiency loss?
a. Diode
b. Resistors
c. Inductor
d. Capacitor
6. What is a possible replacement for the Diode?
a. Resister
b. Inductor
c. MOSFET
d. Capacitor
PPSoC120
1. What applications does the discontinuous conduction mode (DCM) occur? (select
all that apply)
a. DC-DC converters
b. Inverters containing two quadrant switches
c. Converters containing two quadrant switches
d. Inverters containing four quadrant switches
2. Which properties of a converter changes during the discontinuous conduction
mode (DCM)? (select all that apply)
a. Conversion Ratio
b. Output Impedance
c. The Nonidealities of the components used
d. Supply Voltage
3. What is the transfer function for buck converter during DCM?
a. Vo=Vin*(D1/(D1+D2)
b. Vo=Vin*(D2/(D1+D2)
c. Vo=Vin*(D1+D2)/D1
4. When does DCM typically occurs?
a. with large inductor current ripple in a converter operating at light
load and containing current-unidirectional switches
b. with small inductor current ripple in a converter operating at heavy load
and containing current-unidirectional switches
c. with large inductor current ripple in a converter operating at light load and
containing current-directional switches
5. At what conditions do continuous and discontinuous conduction modes occur?
a. CCM:I > iL, DCM:I iL
c. CCM:IV> vC, DCM:V vC