Low Voltage Power Supplies I - a PDH Online Course for Engineers, Architects and Surveyors

Low Voltage Power Supplies II - Linear Regulators

Course Outline

Voltage regulators are a mechanism for providing a fixed DC voltage that does not vary from its nominal value under changing conditions of the input to the regulator and the load drawn from the regulator. Linear voltage regulators are one of the two major types of regulators; linear and switching; They can be found in many of the electronic devices found in the home and work place.

This course is the second in a three part series about Low Voltage Power Supplies. The first part, Linear Voltage Power Supplies I, was an overview of DC power supply designs and architectures. Linear voltage regulators were introduced and discussed at a very high level. This course goes into detail about design considerations and the operation of linear voltage regulators. Principles of operation are explained in detail and insight into their design is presented. The course includes the design of a linear voltage regulator from discrete components and how integrated circuits can be used to replace major functions. The design of high current voltage regulators using multiple low current regulators is presented. The audience should be familiar with principles of transistors and circuit theory to effectively use the material presented.

After completing this course and the previous course in the series, Low Voltage Power Supplies I, the attendees should be able to design a basic fixed, low voltage, regulated power supply. The audience should also be able to understand how to select commercial power supplies for a particular application.

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will:

Understand the principles of operation of linear voltage regulators;
Be familiar with the major building blocks of linear voltage regulators;
Be able to design a low voltage power supply using discrete components;
Understand stability issues in linear voltage regulators;
Understand the operation of integrated circuits that perform major functions of a voltage regulator;
Know three protection mechanisms commonly found in integrated linear regulators;
Understand how to use low voltage, low current voltage regulators to build low voltage, high current voltage regulators;
Understand the pros and cons of using linear regulation in low voltage power supplies.

Intended Audience

This course is intended for electrical and computer engineers that may need to design or understand the operation of low voltage power supplies, and for engineers in other disciplines that need to understand power supplies as used in the monitor and control of engineering processes. The audience should be familiar with principles of transistors and circuit theory to effectively use the material presented.

Benefit to Attendees

Attendees of this course will understand the design and operation of linear voltage regulators.

Course Introduction

Direct Current (DC) power supplies are a requirement of most electronics devices including appliances, computing equipment, mobile devices, radios, televisions, industrial equipment and a whole host of other products. Unregulated DC sources, such as batteries or those derived from rectified Alternating Current (AC) sources, often do not provide the level of precision and accuracy required by modern electronic circuitry. The problem with these unregulated sources is that the output voltage of the power supply changes too much for changing conditions of the input or output. Series resistances inherent in these unregulated sources result in a DC output voltage that will increase or decrease with increases and decreases in the current drawn by the load and with increases and decreases in the input source voltage to the supply.

The magnitude of these changes is too large for many classes of applications. Computing devices, sensors and actuation devices often need a more precise DC voltage. Linear Voltage Regulators react to these varying conditions by continuously measuring the output voltage and comparing it to a fixed reference voltage. As the DC voltage changes due to external conditions the difference is sensed as an error signal that is feedback to a device that increases or decreases the output voltage until the reference and the output are again equal.

Course Content

This course content is in the following PDF document:

Low Voltage Power Supplies II - Linear Regulators

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Course Summary

This course is the second in a three part series about Low Voltage Power Supplies. The first part was an overview of DC power supply designs and architectures. Linear voltage regulators were introduced and discussed at a very high level. This course goes into detail about the design and operation of linear voltage regulators. Principles of operation are explained in detail and insight into their design of is presented. Issues in the design of a linear voltage regulator from discrete components are presented, and how integrated circuits can be used to replace major functions. The design of high current voltage regulators using multiple low current regulators is presented.

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.