Switching Power Supply Design Handbook on Apple Books and Google Play Books

My books besides Amazon are now available in an electronic form on Apple and Android devices. You can have them particularly on your phone. Here are the links:

Switching Power Supply Design: A Concise Practical Handbook: Apple Books and Google Play Books.

Home Generator: Selecting, Sizing and Connecting: The Complete Guide: Apple Books and Google Play Books.

Both books may be previewed on Google books- search for the title. Note: if you view an eBook in pdf format, be sure to set your app to "Original Pages" rather than "Flowing Text" for proper rendering.

Fingerprint Login Stopped Working- The Fix That Works

Microsoft Windows updates are notorious for screwing up things that used to work. In my case, fingerprint sign in suddenly stopped working after another Windows 11 update. When you search the web for a solution, you will find many suggestions like updating the driver, clearing cache, etc that don't work (otherwise you would not land on this page). So, here is how to fix it (at least, how it worked for me).

Click Start button and type Registry Editor in the search bar. Open Registry Editor and scroll down to biometrics folder. It may be located in different places. On my Dell Inspiron it was here: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CspSchema\passportforwork\device\biometrics

If you can't locate biometrics there, you may try "Find" menu and search for it. It definitely should be somewhere under Microsoft. This search BTW works very slowly- it may take long time to finish.

Once you open biometrics, if default value is not set, click on it and enter 1. Write down the full path to folder where you did, so you can always undo it if you got any problem with it. Hope it helps. Good luck!

Engineers Salaries 2023

 Electronics Design magazine published its annual salary and career survey. About 70% of the engineers said that engineering is still a secure career, and is as promising a career path as it used to be. And what good for the engineers, is the engineering shortage remains: it is difficult to hire people for new positions, with most companies seeking at least 3-5 years of experience for new hires.  According to a report from Oxford Economics, around 1.4 million engineering jobs will remain open by 2030 in the US. What not so good is 52% companies are already evaluating use of artificial intelligence for the designs. Which means very soon some jobs may be replaced by AI.

What professions are the most wanted? The survey says software and system engineers are the two most often-mentioned jobs needed, but generally there are needs for engineers in all design areas.  All electronic systems obviously need power. Not surprisingly, among all technologies, power management has the main design impact. 

How much engineers are making? 66% of engineers said they had direct compensation $100,000 or more. At this, 53% are making between $100,000 and $200,000. Not bad? In addition to the base salary, 72% of engineers got some kind of bonus. Especially for smaller manufacturers, profit sharing can be a big part of compensation package.

The bottom line is, if you are technically inclined, becoming an engineer can be a right way for you to go.

Message Could Not be Displayed WLM Encountered an Unexpected Problem While Displaying this Message: How To Fix

After upgrading Windows, Windows Live mail app may stop showing the content of the messages. When you try opening an email it will display this error message: "Message could not be displayed. WLM encountered an unexpected problem while displaying this message. Check your computer for low memory or low disk space and try again." 

Here is what you may do to fix it (it worked for me when I upgraded to Windows 11). In short, you need to add these three DWORD entries into the registry: 

RecreateFolderIndex   1 

RecreateStreamIndex  1 

RecreateUIDLIndex    1 

I'll show you step by step how to do it. But first, I want to remind you that if you modify the registry incorrectly the system may become unstable. Therefore, to be on a safe side backup the registry before you modify it. You can then restore it if you did it wrong. Here is a link on how to backup registry . The best thing is to let a computer pro do it for you. Otherwise, you do it at your own risk: see my Disclaimer.

1. To edit registry open search box from START menu and type RUN. In the RUN dialogue type “regedit” and hit OK (you may need administrative rights to open regedit).

 

2. Once you opened the registry navigate to the following folder and click on it:

   Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows Live Mail

3. Select EDIT>NEW>32 Bit DWORD

4. Name the newly created key: RecreateFolderIndex . 

5. Right click on this key and select MODIFY.

6. In the open dialog "Value Data" change from 0 to 1.

7. Repeat steps 3-6 for RecreateStreamIndex and RecreateUIDLIndex 

8. Close REGEDIT.

8. Close Windows Live Mail and re-open.

Note. If your registry already have the above three keys, you just need to modify their value from 0 to 1.

The content of the emails should now appear (you may also need to restart the computer).

How Power Over Ethernet (PoE) Works

Knowing how annoying it can be to watch long videos when all you want is a quick explanation, I put up a How PoE Works video, in which basic principles of PoE operation are explained in less than two minutes. Learn how power can be superimposed onto data pairs in ethernet cables.

What is Power Over Ethernet (poe)

If you have ever wondered about Power Over Ethernet (PoE), here is a quick technical explanation. If you want to calculate the PoE system, get this app.

Intel ATX 3.0 PC Power Supply Specification

19 years after publishing ATX2 power supply standard (a.k.a ATX12V2), Intel has released new ATX 3.0 Multi Rail Desktop Platform Power Supply specification. The main innovation in ATX 3.0 is new auxiliary 12VHPWR connector intended for next generation hardware, such as PCIe 5.0 desktop graphics cards. This connector can provide up to 600W on 12V bus directly to a graphic card. In addition, auxiliary "sideband" pins can communicate to the card the available power of PSU, and can also provide some communication back from the card to the PSU. 

For the details of the new spec, pinout of 12VHPWR connector and designation of the sideband control signals, see our review of ATX 3.0 Connectors and Pinout.

12VHPWR connector

Engineering Salaries 2020

 If you wonder if your compensation is competitive, Electronic Design magazine has published its annual 2020 Engineering Salaries report. 

Median compensation for engineers in 2020 was in the range between $100,000 and $125,000 (21%). 

37% was making $125,000 and over. 

2% was making less than $30,000 (I can't imagine an engineer would accept such a position).

36% did not get any raise in 2020, and 26% got just 1-3% raise. At the same time 22% actually got some paycut, likely because of business decline due to covid-19.

Hopefully, next year will better, especially because he vaccine is already in the pipeline.

Single Rail PC Power Supply ATXVO

Back in 2006 Google proposed single rail PC PSU approach in their white paper. It took 14 years for Intel to practically implement this approach in their ATX12VO Single 12V Rail power supply design guide. However, this is not the end of the road for PC efficiency improvement. Thirteen years ago, in this post I wrote how single-rail 12V power supply efficiency can be further boosted on the system level by updating computer hardware to allow 12V bus to drop to 8-9V. Hopefully, Intel will eventually figure it out. Meantime, here is a detailed description and connector pinouts of ATX12VO power supply.

Airbus to Produce Hybrid-Electric Jet

Airbus has just revealed its plans for production of hybrid-electric jet aircraft by 2035. It is supposed to be a low-emission jet, which is good. They also say that such aircraft will be much lighter and safer than traditional aircraft.

Well, lighter, may be, but safer? Hybrid electric means they will have a lot of batteries. Remember, the introduction of Boeing 787 Dreamliner? At least four of these aircrafts suffered from electrical system problems when lithium-ion batteries overheated and started a fire. And what was the solution? The FAA decided in 2013 to allow Dreamliners to return to service after changes were made to their battery systems to better contain battery fires. Not to prevent fires, but to "better contain fires"! Well, I personally will be reluctant to fly on any electric hybrid jet.

Electrical Generator Animation

For many years I had an electrical generator animation in my webpage http://www.generatorguide.net/howgeneratorworks.html , which explains how generator works. That animation was courtesy of Joe Wolfe at Physclips Project at UNSW. The problem is, it was in swf format which requires Flash player. As we know, Adobe will stop supporting Flash after 2020. As the result, then most if not all web browsers will no longer display Flash videos. You already see this message when you open Chrome. So, I've converted the Flash animation into mp4 video. There are many generator animations on the web, but this one will work beyond 2020.

Electronic Engineers Salary Report 2017

Electronic Design magazine has published its annual Salary & Career Report. You can download full report if you register there. This year according to their poll, average base salary for electrical engineers was $104,996- a bit less than it was in 2016, but higher than in 2015. What's interesting is that 70% of electronic design engineers are over 50-year old. This suggests that young people are not choosing engineering. In my personal observation, intellectually inclined young guys are choosing computer science over "boring" engineering. Among young engineers I see mostly guys from India and Far East.

TI Power Supply Design Seminar 2016

This year TI power supply design seminar (formerly Unitrode) includes the following topics:

• Design of a high-frequency series capacitor buck converter- presented 2-channel buck in which one channel has a series capacitor;
• Flyback transformer design considerations for efficiency and EMI- a new funny way of constructing flyback transformer that supposedly minimizes energy losses due to proximity effect and leakage inductance;
• Switch-mode power converter compensation- a step-by-step process that engineers can follow to compensate a power converter;
• Bidirectional DC/DC converter topology comparison and design- automotive 48-V/12-V bidirectional converter;
• SiC and GaN applied to high-frequency power- examines wide bandgap (WBG) silicon (SiC) and gallium nitride (GaN) power devices;
• Under the hood of a noninverting buck-boost converter- various non-inverting topologies;
• Design review of a 2-kW parallelable power-supply module- CCM PFC front end followed by current mode-controlled isolated DC/DC resonant ZVT phase-shifted full-bridge converter with synchronous rectification.

This year for the first time TI did not publish a complete seminar book like they used to do before, but provided only short slides. The texts of the presentations is not on their website yet- usually they do if after they finish the entire seminar series. Some of the the past seminar topics you can find here.

How to Insert Chapter-Based Right-Aligned Equation Numbers In MS Word 2010

     If you write an article for a journal, a diploma project or a dissertation you may wonder how to insert automatically updated right-aligned equation numbers based on chapters. In other words, for example, math equations in chapter 1 should be referenced to as (1.1), (1.2), etc., and these captions should be on the right edge of a page. Microsoft geniuses somehow used not to think about a built-in method of numbering equations until Office 2016. Having searched the web, I found a cool table-based method provided by Dr.Franklin in this video. However, this video described only a basic numbering, which does not say how to include the chapter number. I’ll show you below how to easily expand this method into a chapter-based numbering.

Most steps are just per the video. First insert table with one raw and 2 columns, and adjust the width of the right column like this:

If you want formulas to be exactly centered on the page, you can optionally insert 3rd column on the left  with the same width as the right column. Type parenthesis in the right column and click inside them. Then click Insert--->Quick Parts --->Field. Scroll down to StyleRef.  You will get a menu like you see below.

Check 'Insert paragraph number' in the Field options, and under Style name select the section which you want to be the base of the numbering. If, for example, your chapters are based on Heading 1, select it in Style name. When you hit OK, it will print the number of the current "Heading 1" chapter. Then type period (dot) and click again Insert--->Quick Parts --->Field. This time scroll down to Seq (which is sequence field). Add a name to this sequence, for example Seq eq.

When you hit OK it will print the number 1. In our example, if you do it in the Chapter 1, the result in right column will look like (1.1). Every time you repeat this procedure the numbers will automatically update sequentially. Optionally, you can click in the main column and then click Insert--->Equation. This will place an equation placeholder there. Finally, select the entire table and get rid of borders.

To simplify the process so that you won’t have to repeat it manually every time you insert a math formula,  you can save all this as an auto text. Select entire table and click Quick Parts--->Auto text--->Save  the selection in auto text gallery. When you will need to place the next formula, you will just go Quick Parts--->Auto text and select your saved auto text. This method will likely work in Word 2013 as well, although I did not try it.

By the way, Equation Editor is an optional component of MS Word. You need to select it when you first install Word.

Drone Package Deliveries

I like an idea of getting a package by a dron. Google recently has filed a patent application on the method of dron delivery. Basically, you will need to print a barcode and display it in a “landing pad”. The article claims the delivery may start in 2017.

2015 Home Generator Review and Buying Guide

Needless to say, the winter is here. During the past decade the number of power outages including weather related ones kept rising across the entire country. In 2014 alone there were more than 200 power disturbances in U.S. affecting over 16 million people. Since most electrical lines in U.S. still use overhead wires, and because of aging infrastructure of our power grid, this trend will likely continue. A lengthy power interruption is more than spoiled food or just an annoyance. It is a potential life-threatening situation. My online guide to home generators provides the basics of backup power. For complete information with step-by-step instructions on selection, sizing and connecting standby and portable models see my new generator review and buying guide. It will save you hours of research and potentially save you money too.

Charging Electric Car from Portable Generator

This video of course is cool, but if I had a BMW I would not risk charging it from a portable generator, even from a sinewave inverter-generator like Honda. And I would never run a gas generator inside a car even with an exhaust hose.

Never Refuel a Portable Generator While It Is Running

If you need to refuel a portable generator, you need to turn it off, wait until its case cools down and only then add the fuel. Refueling a generator while it is operating presents serious fire and burn hazards as one can see from this news report.

HP Recalls Notebook AC Power Cords Due to Fire and Burn Hazards

According to CPSC.gov, HP recalls more than 5 million power cords for HP and Compaq notebooks due to fire and burn hazards. I can understand how a sloppy designed power supply can overheat. But a power cord? Could not HP genius figure our proper wire rating?

One Million Dollar Prize for Next Generation of Power Inverters

Google recently announced their so-called Little Box Challenge, a $1 million prize to develop the next generation of power inverters. If you want to know what power inverter is, here is the basics. Unfortunately, they did not provide any technical details on what exactly they are looking for. The referred website http://www.littleboxchallenge.com/ as of today provides zero useful info either. Hopefully, they will clarify the competition shortly.