# Gas station without pumps

## 2021 November 24

### Contract signed with publisher!

Filed under: Circuits course,Uncategorized — gasstationwithoutpumps @ 10:31
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I’ve just signed a contract with World Scientific Publishing to publish my Applied Analog Electronics textbook.  They first contacted me on 2021 Oct 7 expressing an interest in the book, we met on Zoom on Oct 20, and they had a proposed contract to me by Oct 26, and we had a few back-and-forth rounds of negotiations.  The final contract was sent to me on Nov 19, I signed Nov 21, and they signed Nov 24. So the full process took about 48 days.

Here is the contract:

The most surprising thing in the contract is that they are continuing to let me sell the PDF through Leanpub (and my own web site, if I ever create one).  The royalties per book for Leanpub sales are higher than I’ll get from World Scientific Publishing, and the price will most likely be lower.

I did not use a lawyer in negotiating the contract—I contacted 4 lawyers who specialize in book contracts, but even the cheapest of them was too expensive, as I don’t really expect to make much money on this publishing deal.  I did use two online books:

Now I just have to get the 250MB of source files to the publisher and fill out the promotional questionnaire.  They may want me to make some small changes (like changing the title page).  When they are ready to publish, I’ll have to register the copyright also.

I’ll post here again when the book becomes available in paper.

## 2021 October 1

### Edition 1.3 released today!

Filed under: Circuits course — gasstationwithoutpumps @ 21:50
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I finally released the new version of the textbook Applied Analog Electronics today at https://leanpub.com/applied_analog_electronics. The book is a little longer than the previous editions:

Edition 1.1 Edition 1.2 Edition 1.3 type
659 673 691 pages
337 342 348 figures
14 14 14 tables
515 523 528 index entries
162 162 169 references

The newest edition adds a new section in the active-filters chapter, some additional explanation at the beginning of the FETs chapter, a constant-current circuit for electroplating the Ag/AgCl electrodes, and a few pieces of advice in the design report guidelines.

The chapter on design report guidelines is available free as a separate publication:
https://leanpub.com/design_report_guidelines

The minimum price is still \$7.99, but I’m doing a special one-month coupon that lowers the price to \$5.99, just for my loyal blog readers! One nice thing about selling through Leanpub is that purchasers get all future editions published through Leanpub as part of the price—the company is trying to encourage authors to publish book drafts through them, rather than waiting until the book is completely polished. That means that people who bought (even with free coupons) earlier versions of the book will get this release for free, and anyone who buys now will get the benefit of future releases. I will still provide coupons for free copies to instructors who are considering using the textbook for a course—contact me if you need a copy!

As before, I am still offering 25¢ rewards for the first report of each error (no matter how small) in the book.

I have recorded video lectures for the book. Playlists are at https://www.youtube.com/playlist?list=PLQCrrTKnAE-97LcrJuUQ_5wKBFil8An9i for the first course and https://www.youtube.com/playlist?list=PLQCrrTKnAE–khjVV52ZWU_Usc3e6KV9J for the second course. The first playlist of 122 videos runs about 27:16 and the second playlist of 50 videos runs about 12 hours, so the average video length is under 14 minutes.

There may be one or two videos added and existing ones may be updated, but the set of lectures is essentially complete. Many still have only automatic closed captioning, but the captions will (slowly) get hand edited.

## 2021 September 27

### Next book edition almost done

Filed under: Circuits course — gasstationwithoutpumps @ 13:50
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Eleven days ago, I said

Now all I have to do for the next release of the book is do the standard final checks (page breaks, spell checks, and URL checks).  This will probably take me another week.

I have now gotten the page breaks fixed and checked all the URLs (only 8 of the 215 distinct URLs needed fixing).  I last checked them about a year ago, so that is a link-rot rate of only 4%/year (a half-life of about 18 years).  In the process of fixing the page breaks, I noticed and fixed a few minor typos, as well as tightening the text in a couple of places (to improve the page breaks).  I found one instance of “the the” with my tandem-word checks (probably introduced since the last released edition).

I still have to do the spell checks.

I did release one new video last night: https://youtu.be/vLece-VKfkQ, which talks about providing a constant current for electroplating (see the post Controlling current if you don’t want to waste time watching an 11-minute video).

## 2021 September 16

### Last to-do note in book done

Filed under: Circuits course — gasstationwithoutpumps @ 10:46
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I’ve finally removed the last to-do note from the text book. This one was an explanation of the threshold voltage for FETs as the transition between the subthreshold conduction, where the on-resistance has exponential behavior with $V_{gs}$ and the on-region, where it is roughly constant.

I don’t like copying graphs from datasheets for the textbook, so I needed to measure the values myself to make a plot. My first attempt, using the PMV20XNE nFETs that we used for the past few years in class, was a failure.  The typical on-resistance is only 23mΩ, which is too small for the crude measuring setups and low currents that I could get with the Analog Discovery 2.  I ended up mainly measuring the resistance of the test setup, with errors larger than the value I was trying to measure, so I couldn’t even subtract off the short-circuit measurement.

I tried again with a low-power nFET (a 2N7000), using a constant load resistor of 150Ω (so the maximum power dissipation in the ¼-W resistor would be $(5V)^2/150\Omega = 167mW$).

I controlled with the gate voltage with waveform generator, and measured both the drain-source voltage and the drain current. I used the oscilloscope tool and averaged both within a sweep and across many sweeps to reduce noise.

Because the Analog Discovery 2 has only 2 measurement channels, I had to manually copy the measurements into a file for gnuplot, as there was no way to record the waveform generator output with the measurements in a single file (well, there might be with the scripting capabilities of Waveforms 3, but I’ve not explored them much).

I noticed some pretty large offsets when measuring small voltages, so I did open-circuit and short-circuit measurements and used them to subtract off offsets (with the understanding that the current for the open circuit would be about 150µA, because of the 1MΩ impedance of the Channel 1 measuring the open-circuit voltage).

The corrections make a big difference at the low end, where on-resistance is comparable to the resistance of the measurement instrument and test currents are tiny. The correction at the high end is smaller, but still noticeable. The transition from the exponential behavior of subthreshold conduction to the on-region is pretty clear. (Click to enlarge)

Now all I have to do for the next release of the book is do the standard final checks (page breaks, spell checks, and URL checks).  This will probably take me another week.

## 2020 September 11

### Edition 1.1 released today!

Filed under: Circuits course — gasstationwithoutpumps @ 11:49
Tags: , , , ,

I finally released the new version of the textbook today!  (https://leanpub.com/applied_analog_electronics). The book is only slightly longer than the previous edition:

659 pages
337 figures
14 tables
515 index entries
162 references

The chapter on design report guidelines is available free as a separate publication:
https://leanpub.com/design_report_guidelines

At the same time as I released the new edition, I eliminated my COVID-19 sale, so the minimum price is now \$7.99. I will still provide coupons for free copies to instructors who are considering using the textbook for a course.

I may have to do another version before January, as I have not checked the labs for BME 51A yet to see what modifications are needed for doing the labs at home. For example, I haven’t decided whether it is worth buying more blood-pressure cuffs and extra tubing, to have enough to ship one to everyone. I’ll probably have to give up on the drill-press instruction. I’d rather not skip the micrometer instruction, but that would mean buying a lot more micrometers, as we generally share 5 for the whole class.

One nice thing about selling through Leanpub is that purchasers get all future editions published through Leanpub as part of the price—the company is trying to encourage authors to publish book drafts through them, rather than waiting until the book is completely polished. That means that students who got earlier versions of the book will get this release for free, and anyone who buys now will get the benefit of future releases.

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