Quote from: MileHigh on May 16, 2012, 11:59:23 PM
So what is booster converter mode?

Careful.... you are ASKING A QUESTION.

She has heard the Joule Thief referred to as a boost converter. And she would like her circuit to approach the Joule Thief in efficiency and ability to generate interest. There is no chance of that happening.

Here is what a "real" set of problems in electronics engineering looks like. Actually the ones on the left are just "exercises" to get you ready for the "problems" on the right.

This is what you get exposed to by the 3rd week of your sophomore EE classes at a real University, and you had better be able to keep up, because there are a lot of Chinese and Persian and Indian students who can indeed keep up and you will be competing with them for grades and jobs.

I can do all these problems --- AND GET CORRECT ANSWERS --- and I have done so.

Ainslie?  Somehow..... I doubt it.  But I'm willing to watch her try. Just do one, Ainslie. I made the screenshot extra large so that even you can probably read it, if you squint and get up really close to the screen.

This is of course from Circuits, Devices and Systems, 3rd Ed, by Ralph J. Smith.

I am still waiting for proof of ANY of Ainslie's allegations and LIBELS about me. Meanwhile I am ready to prove any and all of my allegations about her, and I keep doing so, over and over. But it's like running over a dead armadillo: no matter how many times you do it... it is still a dead armadillo.

When does AC become DC?  Part 1.

http://www.youtube.com/watch?v=jg2_yE5dEQg

Okay TK, look out because I have been trying to make pretty pictures again.

Note there is a timing skew of about 150 nanoseconds between the two traces.  This may be explainable by the wire lengths.  This is a rough outline of what I think is going on.

Think about this:  You are opening and closing a valve.  When the valve closes the inductance charges up the drain-source capacitance.  At maximum voltage the current flow stops.  Then the current flow reverses direction and the capacitance simply discharges through the whole circuit.  When this happens, the current starts at zero, reaches a certain negative maximum current, and then drops towards zero again.  The fact that the MOSFET is off does not stop the current flow at all.  The MOSFET is acting like the capacitor in this case, and there is nothing to stop the current from flowing from the point of view of the capacitor.  Then the MOSFET switches on and the current starts to flow clockwise again.  The voltage is low and normal in this case because the cap has just finished discharging.

Here is the key point:  When the DSO is recording "negative power" this corresponds to the time when the tiny capacitance is discharging, the current is flowing backwards, and the MOSFET switch is off.  So the "negative power" is not "zipons" and "binding material," it's just the very tiny capacitance in the MOSFET discharging.  The "load" for the tiny capacitance is the battery and the load resistor.  It's almost certain that this tiny little nugget of energy is mostly burned off as heat in the battery and the load resistor.

MileHigh

Just a little bit of soapbox editorializing:

You can stare at DSO captures and scope traces until you are blue in the face.  You can crunch numbers in real time with a DSO and do amazing things.

However, you have to realize that the squiggly lines are not just "cool waveforms."  Every single aspect of every recorded waveform means something and there is reasoning and an explanation behind it.  If you really want to know what is going on you really have to understand the waveforms and what they mean.

The whole Ainslie/NERD testing was basically an exercise in empirical observation.  No attempt was ever made by the NERD team to _explain_ the waveforms.  In sales you would say that the NERD team were just "order takers," they didn't take the initiative to go out and sell.

So I just made a early rough attempt to explain, _actually explain_, what was going on during the NERD testing based on a recent DSO capture posted by TK.

And that's what engineering and working with circuits on the bench is supposed to be all about.  And we all know that your typical pulse motor builder scopes the signals on his pulse motor but almost never attempts to explain what he is seeing.  He might ask for the wire gauge, the number of turns, the coil dimensions, and then when he looks at the waveforms on a scope he doesn't question what he is seeing.  Team Ainslie suffered from the same problem.  Rosemary was not capable of deciphering the meaning in the waveforms, but you would have hoped that somebody else on the team could.

MileHigh