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Unformatted text preview: le rejection this at these particular frequencies? (3 points)
The frequency of a full-wave rectified since wave is twice that of the original since wave. For
mains power supplies the input is 50—60 Hz so the output is 100—120 Hz. Thus, the
performances of three-terminal regulators and filter capacitors at these are of interest to
Problem 6 Each of the circuits below has a serious flaw. Identify and briefly describe the
serious them. (6 points) (a) (b) Circuit (a): One cannot generate a negative voltage using the 7915 regulators as the figure
Circuit (b): There is no smoothing capacitor after the bridge rectifier 9 55:041 Electronic Circuits. The University of Iowa. Fall 2011. Problem 7 Modern three-terminal linear voltage regulators are very easy to use, and a great
boon to designers. However, a caveat with most of these regulators is that they require two
(see below) for reliable operation. (6 points)
(a) Explain the purpose of and .
(b) If these capacitors are so important, then why don’t IC manufacturers integrate them into
their regulators? (a) The regulator is a control system that monitors the output and makes adjustments as the
input (line) voltage or output (i.e., load) voltages fluctuate. These capacitors ensure
stability of this control system.
(b) Capacitors values of
are too large to integrate into ICs. They will consume
too much IC ―real-estate‖...
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This note was uploaded on 10/26/2013 for the course ECE 55:041 taught by Professor Kruger during the Fall '11 term at University of Iowa.
- Fall '11