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Finally I see someone got it right. Current is coulombs/second, so integrate over time gets you Coulombs, 1 Coulomb is something like 10^^19 electrons, 1 ampere is 1 coulomb per second, the integral then is the total charge that flowed through the wire.

+meettechniek This guy has it. Ampere is defined as a Coulomb per second so the integral of current over time will give you a unit of charge. For the energy you need the power (which he is getting from multiplying the voltage and current). Since power in Watts is defined as a Joule per second, the integral will result in a number of Joules of energy.

Oranje boven, Oranje boven leve de koningin !

if your voltage is constant you can just multiply the integral of the current by your voltage, like Dave said in the video

There is an offset softkey when using the integral function on the 6000 right? I see it's on p167-168 of the user's guide.

***** That offsets the output, not the input

mike i love your video's keep it up!!

TheHue's SciTech Yes, when it's that low down, offset will certainly be a huge contributor, I forgot to mention that, thanks. But ultimately at this level you are down into the LSB error territory. 1.4V peak at 8 bits, basically gives us that 12uV we are seeing for example. Better in high res mode, but basically not good enough for an accurate reading on it's own in this case.

EEVblog I suspect quantization error can be ignored (or more accurately, divided by a thousand) when a) you're integrating over possibly millions of samples and b) you have analog noise that is dithering your signal for you, making the quantization noise DC-free as well. Having said all that though, annoying other effects like INL could cause issues. I'm going to do some experiments right now... :-)

TheHue's SciTech But you are going to hit the ground at some point! (pun intended) There are practical limits to what resolution you can get out of a scope in this example.

EEVblog Also, keep the limitations of the uCurrent in mind. I guess, that some issues can be traced down to the uCurrent. Those pikes in idle "current" could be auto-zero artifacts and at the low end of the range, the Output Offset Voltage of

sarowie What is a pike?

(sry for wall of text) It all depends on the persons interest. Math is only awesome when you are able to use it to get work done. This is largely why most students become disinterested in math once half way through middle school. That is the point when the math becomes less and less relevant to what the student sees in the world around them. More basic math can hold the interest of a wide range of students as they can learn it in school and be using it in a productive capacity that same day in the real world, or see people in their community using it. this reinforces the motivation to learn it. For example It is easier to get a student interested in division if it helps them calculate the price per gram of various foods that they like to buy, in order to find which is the best deal, but it will be an uphill battle to get most middle school and some high school students interested in calculating the 95% confidence interval on a set of data they collected, and then represent those calculations in standard deviations. Now if they get into a field that requires those calculations, then they will be more interested in it as they will have a use for the math they are learning. On top of this, if a student is forced to learn math or any other content that they have no use for, then the odds of them retaining the knowledge is very low as they will not go through many of the vital stages of the learning process which increases the likelihood that they will retain the knowledge. They essentially need to go through Knowledge> Comprehension> (then repeating some or all of the latter in real world) Application> Analysis> Synthesis> and Evolution. The higher level thinking cycle keeps the skill fresh. When students are learning a skill that they cannot practically make use of in the real world, then after the knowledge and comprehension stage, everything from application to evolution of what was learned, is done in a more synthetic fashion that will likely never be repeated in the real world, and due to the synthetic nature of the higher order thinking levels of the learning, reduces the likelihood that the skill and knowledge will be internalized as the synthetic nature makes the work less fulfilling, as it will not provide the same sense of accomplishment as putting the skill to use in the real world and making a difference in the lives of others, or making money through the use of the skill.

Razor2048 You've pretty much summarized all that is wrong with the modern education system, which wastes away an unforgivable amount of time. People justify this hamster wheel as "imparting a sense of discipline", but that can be done concurrently with a far better learning structure. There will always be people who will grab a textbook and go through it meticulously and collect their A+. Those people are not the majority, yet they're used as examples of how students "should be". For most people, unless there is a tangible degree of passion behind their efforts, it's all a huge waste of this short life on our planet... The school system, which certainly includes universities are like impenetrable fortresses which are not to be messed with by mere mortals. Advice is only ever dispensed, never considered.. and the people running them have a sense of immunity from criticism or wrongdoing alike. The good news is that the internet has been slowly changing all that and eventually the school system will adapt.

Razor2048 Nah Math is always awesome.

***** Yep, mathematics are very beneficial in life, the issue that many schools face, is building intrinsic motivation. For lower level math, the schools do not have to do much to build it, as its application is visible outside of school. When it comes to higher leave math, then there needs to be more effort put into motivation, if not then many students will simply not retain it, and become really bad at it. Wanting to learn math out of pure interest, is even harder, especially (at least with the schools in the US) where higher level math does not go much beyond finding the right formula to use in order to get an answer. Because of the way we learn it, if we cannot find a practical application for it that we can engage in outside of school, or have the drive to learn it due to a future goal that will require the skills, then the math will be avoided as much as possible. Not sure how much worst it gets in other parts of the world generally schools will focus on formula and application, and unless you can find the motivation to remember how to use the formulas, you will have a lot of trouble with more advanced math. In my personal experience, the merits of math were never thought, instead, the schools used threats and punishment to teach math. Essentially the only reason why you would learn the math, was because if you did not, you would get a failing grade, and possibly incur other punishments. Overall, the focus was on the bad things that other people in authoritative positions would do to you if you did not learn it rather than the merits of learning the math. The end result is that math became an unpleasant experience that we had to endure or they will subject us to other unpleasant experiences. We did not really learn the benefits of higher level math until we were pretty much done with higher education.

***** Truthfully I see your view of reality as poisonous. That said, I agree that math in its pure form is a great thing to encourage for those who have a capacity for it. Math above all is a way to see a world of connections that are completely invisible unless a person puts much of their time into climbing that mountain. It's not for everyone, but it is everything! (ha) Onto the bad stuff: -The world does not subscribe to solipsism. You exist with others and have to find harmony with them, not shun them like your ego tells you to... -"Stupid" is a subjective qualifier that has philosophical roots for each person; you cannot turn it into something absolute. -There will always be someone a lot smarter than you, who might (just as wrongly) consider you stupid. Don't play that game, it won't do you any good. -Peoples' natural passion is not extinguished so easily by the presence of others who slow down their momentum and somehow force them into underachievement.. the latter is a personality issue above all. -The mentality that gives you a sense of superiority over others because you consider yourself intelligent, is the same mentality that created slavery where the select few grant themselves the right to police everyone else they deem inferior using various garbage as qualifiers. Calm your inner villain. -What lets people achieve far reaching goals is self-discipline and focus, not having the world babysit them until they magically blossom.. or otherwise blame the world for having had failed them. History shows much hatred for early scientists and mathematicians who challenged the status quo with their ideas... -Algebra is a lot more useful than calculus specifically for people who aren't trying to become engineers (majority). Many jobs require some algebra knowledge, and reaching that will make a difference between a person having a half decent job, or not. If they're forced into an even lower job, it drags down the average of the world in which you live. Accept that math can be utilitarian, and help people come to terms with it when it's not their strength but rather a necessity. -A person who has made it to mid-level calculus is more comfortable with math and should not require constant babysitting to the same degree. -Postgrad math is incomparably harder than the examples you've listed, it ends up as a lifelong commitment to a very specific area for a researcher. Everything is relative. -The goal of education is not to breed unwieldy geniuses; it's to keep raising the general level of education of ALL members of society. That is how you decrease poverty, reduce crime, and give people options in life that make the world better for everyone, not just you... -We already have organizations that specialize in breeding geniuses: Google, Apple, Microsoft, JP Morgan, Tesla, SpaceX etc. Feel free to apply and enjoy. Some of them are great companies. :) Sorry if any of this sounded harsh. You're welcome to disagree, but this is not the right place for these discussions and I've spent sufficient time here already.

SixThousandMono There is no "voltage waveform", it's a constant supply rail. So the area under the curve is effectively the energy.

AnalysIRchannel The pulses are too quick for the DMM, so not a problem.On a DSO without integration you can print the screen out on a transparency and then put over graph paper (or vice-versa) to get a finer grid to count squares with. But then you have to take care not to goof the units conversion.

EEVblog Or we can export the data of the scope, and get the points (x, t) and plot on math softs. And then get the area too. Easier than count squares on bare hands... IF the scopes can export data in values... Another way could be aproximate by a know function (sin, exp, step, etc...) and solve by math (or softs again). Probably many people know that, but to keep this ideia to all others...

Mario Sbampa This scope can export data. Even Mid- and Low End ones can do that.

sarowie Any modern scope that can export data most likely has an integration function anyway.

EEVblog I appreciate the purpose of the video was to show a use for the Integrate feature. Would the Vavg measurment feature work also, if the display was scaled correctly? units adjusted etc... Anyway, if I get some time I may try to implement some of the more useful features not on my scope, via the USB data connection. On the PC of course. I dont think the relatively common low end rigol DS1102E series has integration? but can export data. So might be a fun project to add some of those features in offline.

***** Thought about the white board, but seemed a bit too much effort! and the real info was on the scope screen anyway.

EEVblog no worries, this video was one I really learned alot from.

jeromekerngarcia The point of this was to get the average current so that you can calculate battery life etc. Just multiple by the supply voltage to get power.

EEVblog Thanks Dave. I see ProfessorLesh posted a similar answer before I asked my question. Lesson for ME to "rtfm", eh?

Bernhard Wörndl-A. In this particular example the pulse is not wide enough or frequent enough to be included in the multimeter average reading.But in any case the whole point of the video is to show people how to use the integration function on a scope in a practical example.

EEVblog I'd really like to see the difference in the multimeters average value when you turn off the frequent wakeups of the mcu. I suspect that the average value will drop acordingly. You selected the Min/Max/Avg measurment of the Fluke, so it should actually have captured all pulses.

frollard Yes, of course, and I explained that it's actually microamps later in the video.

Scripting is not the right thing for him. But staying away from Math and RF would help a lot. Both appear to cause him more trouble than anything. And that's fine, everyone has their special area. Trying to expand one's horizon and learn something new is cool, trying to teach others if only equipped with basic knowledge on the matter is not. And even that wouldn't be an issue if he'd stick to what he does know. The above video would be worth just as much without Dave trying to play math teacher. But most error overlays happened when he tried to do so. There are tons of great videos on how integrals work out there. Refer to them for explanation. Next thing is learn to admit errors. Prefacing it with "Technically...," sound like the error was just that, a technicality. If I call a car a submarine and then say "well, technically, it's a car," it kind of abuses the meaning of "technically".

What's the big deal? I used the uVs because that is what is actually displayed on the scope when you do this. I mentioned later because I'm using the uCurrent that then translates into current. ARe people complainign because I didn't do that from the start? And because it's a constant supply voltage this also translates into energy.Yes, I'm no math teacher, and I don't pretend to be, I'm just trying to explain how to integrate under the curve on a scope using a practical example people might encounter. I don't understand the nit-pickieness here?When have I ever not admitted and corrected errors?Frankly I don't see any major errors here in what I did or said.Could it have been better explained? Sure, always.

EEVblog And also (can't seen to edit comments any more?), there will always be my usual mis-speak's when I shoot off-the-cuff video like this. Often these get detected and annotated in editing, but not always.My brain and my mouth are only loosely coupled.

EEVblog nononono!!! I was aiming that @audience. IF a person were being confused by the volt-time units they need to remember that its current-time which equates to total energy :) Yes, later in the video you cover this in an excellent fashion. I only brought it up because at first I thought ...hmmm...volt-seconds, that's weird, oh right, the microcurrent! It was hopefully constructive feedback, not even aimed at you the presenter! As for KF talking shit about scripting - keep being awesome, nothing needs to change! I have learned BEYOND textbooks worth of industry knowhow and cleverness that I never would have stripped from the pages of any book.

My guess is that there is no point basically. In the context of audio, when you want to apply noise reduction, the implication is that the noise floor of your source file is far higher compared to the total dynamic range of 24-bit or even 16-bit audio. Taking a "silent" sample and subtracting it from the main waveform (a form of convolution I guess) makes sense in that context, though it invariably introduces artifacts at full strength. Quantization noise in audio is sometimes a problem when converting from 24-bit to 16-bit audio, where the quantization noise may become audible making it necessary to dither the signal (introduce structured random noise) to mask the less natural sounding quantization noise. In the case of oscilloscopes, their intrinsic noise is tiny with respect to the total signal range available at any given time. Removing that noise won't get you any more precision since you're limited by the ADCs regardless, and the best thing you can do is use the high resolution mode like Dave did, which is a sort of temporal averaging that comes at the expense of losing some high frequency information. There is something to be said about conditioning and increasing the SNR of a signal prior to feeding it into a scope though, which is a common occurrence in communications. This can be done digitally through DSPs/FPGAs or using fancy analog filtering, or both. In general, it's more of a concern to make sure that a signal has good SNR and can fill the entire range of the ADCs to minimize quantization errors. It's conceivable that a signal could have critical areas of both high and low swings, making it impossible to analyze on an 8-bit and even 10-bit scope, so all kinds of specialty digitizers and general methods exist to deal with that in the scientific world.

You might be able to do that in a hokey way with an arbitrary waveform generator -- you can record the noise with the ArbGen, then replay it back on a second channel on your scope. Then you can apply a Math function to subtract the noise channel from the signal you're actually trying to read. I'm not an EE but I think that might do a decent job.

Oh, and if you meant to imply to use this noise reduction as a kind of DSP operation within the scope to condition the digitized input signal - it's technically feasible but would require quite a lot of computation power from the scope. Scopes already struggle doing simple averages on large sample sizes. Since the signal is digital at that point anyways, in most cases you'd want to get the signal into something like matlab and perform your filtering there. Maybe this kind of function already is or will be available in top-end scopes though, I'm not sure.

TheSageDad Usually the exact nature and frequency distribution of the noise has to be known (or very accurately guessed) in order for this to work, otherwise you would simply be introducing that noise to the main signal. Subtraction is the same as inversion followed by addition. Since noise is random, inverting it won't make any difference and you would simply add noise to your source signal. In order for that not to happen, your generated noise would have to cancel out with the noise in the source signal. This can only be done statistically, which can become quite complex mathematically.

whatlions One thing to keep in mind: The scope has a low noise front end. but Dave is using his uCurrent. I would guess, that the error and offset of the uCurrent dominate other types of errors in this particular measurement. For e.g. as the Op-Amps in the uCurrent are auto-zero, I wonder if some of the artifacts on the scope aren´t auto-zero artifacts. Also the uCurrent has an issue with measuring small signals (compared to full scale). That is common for anytype of measurement instrument, but the uCurrent has only three ranges.

the scope does it digitally, as a side effect a capacitor would have caused a phase shift, which, as you'd expect some resistance wouldn't just be 90°, but something frequency dependent, you'd see a big differece in the waveform

Elden Chang Please tell me precisely what I got wrong and I'll correct it with annotation.

EEVblog I think he meant the same error as I tried to touch upon in my earlier comment. You talk consistently about energy when pointing out the area under the current curve. But this is the charge. Charge (A*s) and energy (V*A*s) are two different parameters.

meettechniek Yes, point taken. I used the word energy in the wrong context here, I was trying to talk in a general sense by using that term.

EEVblog Yes, Dave it was about the area under the curve. In order to get the area to be energy under the curve, you need to integrate the "power" and not the current. In your circuit, you can easily also measure the the voltage and in a first step multiply it with the current. The Agilent 3000X allows you to make a two step MATH function. First your multiply current and voltage and then you integrate the results. The units will even show up in Joules.

Elden Chang Yep, certainly should have done that. I was too focused on simply getting the final current value.