P STYLE=" margin-top: 12pt;" CLASS="Normal">1: All things being equal (such as output power), why do switching
power supplies weigh so much less than (and are

    also physically smaller than) an equivalently-rated
linear power supply?  Assume both supplies plug into the

    wall, and convert 115 VAC to a low voltage such
as +5 VDC.

In a switching power
supply, the line voltage is directly rectified and filtered, allowing
for the use of a small, lightweight transformer to reduce the voltage. 
In a linear power supply, a heavy transformer is required to convert
the line voltage.

2: Of the following sources of electrical power, which is the cleanest
(i.e. which introduces the least amount of electrical noise?): Lindear
power supplies, switching power supplies, DC generators, batteries.

Batteries are the cleanest
and most portable power available for electronics.

3: List as many design considerations as you can that you would take
into account when attempting to design a

    micro-power circuit.

..

4: For the linear voltage regulator that you read about (the LM2940T),
what range of inputs are acceptable for you to

    expect this device to operate properly?  Describe
the inputs as thoroughly as you can, not just the range of input

    voltages.

..

5: You can use a transformer to convert 60 Hz AC power at 115 V to
other voltages, both lower and higher than the voltage supplied. 
Can you use a transformer to convert DC voltages to higher or lower
voltages?  Explain why you can or cannot do this.

..

6: What does a rectifier do?

A rectifier converts
alternating current (AC) to direct current (DC).

Honor Code:  I have not given nor received any aid on this examination,
nor have I concealed any violation of the Honor Code.

[signed]    [signed]    [signed]  

Debby Chen   Lindsay Harding   Michael Millat