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Efficient Switching Regulator
for the PowerToad
- Itty James Samuel
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Design an efficient switching regulator
Software interface to Multisim
What is the PowerToad?
www.powertoad.com
2 - AC to DC voltage
Converter
Laptop Computer with
USB
6 - A product
specific
connector.
6
Variable DC
Power
1
AC input
5
2
6
USB
4
3
5
Pod
Power
Appliance
DC Power
Circuitry
24 V DC
input
Ethics
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Fire hazard of new switching regulator
solution
The implemented solution damages a device
Copyright infringements of the design
Historical Review
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Different topologies of switching regulators
Buck regulator most commonly used
Techniques to make buck regulator more
efficient
Buck Regulator
Q1
L0
I Q1
T on
VO ~ Vdc
T
IO
R1
Vdc
V1
D1
EA
C0
Vea
R2
VREF
Current/
voltage
Amplifier
VT
PWM
Vwm
Considerations for efficient design
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Increase the duty cycle
Two-stage device
Earlier designs used the same idea, but had voltage
spikes due to leakage inductance
An extra inductor winding is added to compensate
voltage and reduce spikes
Soft Switching
MultiSim 7
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Java interface to simulate buck regulators
Enter values for a switching regulator
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Vin, Vout, I (current), Vref
Interface produces a netlist, which can be
imported into MultiSim
Calculates Inductor, capacitor, and resistor
values
Milestones
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Discuss with PowerToad Executives
Design
Simulation
Develop simple interface to Multisim
Implementation and replace old circuit
Experiment