PHYS 427 A: Applications of Physics

Physics 427 - Winter 2024
Special Topics: Creative Electronics

Instructor

David B. Pengra
Office: Physics/Astronomy Building, Room B256A
Phone: 543-4783
email: dbpengra@uw.edu

Class Hours

Lab: Physics/Astronomy Building, Room B280

Monday and Wednesday 10:30 am - 1:20 pm

University Policies - A number of UW policies affect this course

Texts

The Art of Electronics, 3e, Paul Horowitz and Winfield Hill (Cambridge University Press, Cambridge, 2015). Required.

Learning the Art of Electronics: A Hands-On Lab Course, Thomas C. Hayes (Cambridge University Press, Cambridge, 2016).  Recommended.  The "Learning" book has lots of practical advice and examples.

Overview

This is a student-driven project-based course.  Under the advice of the instructor, students carry out a self-directed project of study in electronics beyond topics typically covered in Physics 334 (Analog Electronics) and 335 (Digital Electronics).  The aim of the course is to give students the experience and practice of teaching oneself aspects of a complex field by learning to solve real-world experimental problems in electronic design and implementation.

The course grade will come from a combination: participation + weekly notebook that records progress, ideas, and experimental information + a written summary due at the end of the term + the students' own self-assessment of their efforts and learning.  There are no exams.

The course may count towards satisfying one of (1) an elective, (2) an advanced laboratory, or (3) independent study (i.e., physics 499).  If the student opts for the independent study, they must complete and file an independent study "contract" with the advising office.

Rationale

Electronic circuits form the "connecting tissue" of virtually all experiments in physics.  From sensitive preamplifiers connected to transducers that convert a physical phenomenon into an electrical signal, down through successive stages of amplification, signal filtering, timing adjustments, signal combination with other sources, and into the data acquisition equipment and subsequent processing, each step depends on the operation and characteristics of individual electronic circuits.  How are these circuits designed?  What sets the constraints that determine component selection and circuit design?  How, indeed, does one design a circuit to accomplish a particular task?

This special topics course will allow students to confront such questions directly.  Students will build on foundational knowledge they have learned in physics 334 (and perhaps 335 or other advanced labs) to direct their own investigations and study into circuit design and implementation. Along the way, they may need to learn about a variety of more advanced topics, such as the following:

• Amplifier design with discrete (i.e., individual) transistors, both BJT and FET.
• Low noise circuitry.
• Low-power circuitry.
• Signal processing and noise suppression (e.g., filters, lock-in amplifiers).
• High-speed and high-frequency design (challenging!).
• Power design (high-current control) & power supplies.
• Analog/digital interfacing.
• Pulse amplification and pulse smoothing (used in nuclear/particle experiments)
• Process control and feedback (e.g., temperature control)
• Signal generation (oscillators, pulsers, and similar).
• Programmable logic circuits (e.g., FPGAs).
• and anything in the Art of Electronics not covered in physics 334. . .

The project-based, self-directed model of this course means that there is no set content.  Lectures will be few, mainly limited to some examples and course management issues.  Students will learn to teach themselves, and thereby learn a skill they will use for the rest of their careers.

Rules

The following are rules. The first two are safety rules and are required by University policy and Washington State law.

• No food or drink may be consumed in the lab. Washington State Law forbids the consumption of food or drink in these labs because they are officially "radiation laboratories:" there are radioactive substances in the lab.
• No students may work in the lab without the nearby presence of lab staff. A TA or instructor may allow students to work independently if they deem the student competent to handle lab technology safely and a responsible staff member is nearby (in a lab or office on the 2nd floor B-wing).

Experimental groups are limited to two persons. A three person group will be allowed only after consultation with the instructor. Four person groups are definitely not allowed.

Every person is welcome in this course.  Instances of discrimination (e.g., shunning, belittling, bullying, harassment) for any reason (e.g., ethnicity, religion, sexual orientation, gender identity, different-ability, or political beliefs) will incur thorough investigation and possible sanction through University approved processes.  If you believe you have been subject to such discrimination, please contact the instructor directly, or see University Policies for information on how to contact University officials.

Course Structure

Participation & Lab Attendance

Students are expected to work a minimum of 5.5 hours/week in the laboratory, during the stated class times, unless specific alternate arrangements have been made.  The instructor will be present during these lab periods, and classroom participation will be recorded.  Occasionally the instructor will use part of the lab meeting times for some lecture and class discussion (mainly toward the beginning of the term). 

Outside Study

As with most advanced lab courses, students will be expected to read and learn outside of lab meeting times.  Apart from the textbook, they should learn to read manufacturer information such as data sheets, use examples, and application notes.  In addition, students should learn to use circuit simulation software to model circuit ideas and designs before constructing prototypes in the lab.  Outside study is expected to take about 4 hours/week.

Lab Notebooks

The most important record of your work will be the lab Notebook.  Everything that you do on your project should be recorded in the notebook, which will be kept online in a shared document.  "Everything" means, for example

• Circuit diagrams (take a picture or screenshot).
• Photos of scope screens, constructed circuits, or other apparatus.
• Calculations or computer code.
• Comments and explanations of what you did, built, observed, or solved.
• Dates and names attached to the entries.

See the page Online Lab Notebooks for more details.

Written Summary

Near the end of the term, a written summary of your work is expected.  You want to tell the story of your investigations: the origin of your interest, how you selected the topics of study, what learning materials you used (books, papers, videos, etc.), what your main problems were and how you resolved or worked around them, final circuit diagrams or experimental results, and a discussion or assessment of what you learned, built, and/or measured.

The expected length would be about 4 pages, or 2000 words.  You may earn a writing credit for papers that are revised, are written in a more formal style similar to a scientific journal article, and contain an abstract and references.  Please consult with the instructor if you wish to apply for a W credit. 

Project Presentation and Self-Assessment

At the end of the term you will present a discussion of the project(s) you worked on to the other members of the class.  This presentation could consist of a formal talk with slides, a demonstration of your project, or just a discussion using the whiteboard or your own written notes.  What you decide to present will be up to you, and will be largely determined by the nature of your project(s). You should structure your presentation to take no longer than 20 minutes, followed by questions and answers.

You will also be asked to complete a self-assessment of how well you did in your self-directed learning and problem solving, according to a self-assessment rubric.  Your self-assessment and presentation will count for a portion of the course grade.

Equipment

You will be assigned a work station which is equipped with most of the necessary parts and tools. Please follow the lab instructor’s instructions regarding care of parts and equipment. Remember that people in other labs also use the same gear, so you must keep it in order. It is very easy for the parts to become disorganized.

If your project would require circuit components outside of what the department has in stock, there is a small budget than can be used to buy some parts.  Please consult with the instructor to see what the parameters are. (Parts that could be used in other courses or by other projects would get priority.) If the apparatus or circuit elements are very expensive, you may need to decide whether you would purchase them for yourself.

Safety

No PPE (personal protective equipment) is required in the lab for this course.  You are not expected to handle hazardous substances or carry out potentially dangerous operations in most cases.  Depending on your project, some operations could require safety training (like soldering); these will be handled on a case-by-case basis and follow standard operating procedures established by the lab instructor in accordance with University requirements. You should be aware of the fire extinguisher located near the entrance to B280.  You are expected to obey the TA or instructor in case of emergency evacuation of the building.

COVID PRECAUTIONS: Because of the continuing prevalence of coronavirus infection, you are STRONGLY ENCOURAGED to wear a tight-fitting, high-filtration mask (N95, KN95 or similar) when you work in the lab.  You will be sitting very close to your lab partner(s) for a full three hours during your lab session.  An air purifier will be used in the room, and air flow in the Physics/Astronomy building is one of the highest on campus, but it is not possible to enact 6 foot separations between persons in the lab.

Grading

The grades are figured as follows:

Final grades are calculated with this formula:

(grade) = 4.2 * (percent) / 100