Super Low Electrical Energy Meter || DIY or Buy || Is measuring µA/nA possible the DIY way?

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You can buy the Otii Arc here: www.qoitech.com/buy/
Thanks to QOITECH for sponsoring this video.
Previous video: • How to do Electrical W...
HACKED!: Speaker System gets an IR Remote video: • HACKED!: Speaker Syste...
Make your own Power Meter/Logger video: • Make your own Power Me...
Electronic Basics #27: ADC (Analog to Digital Converter) video: • Electronic Basics #27:...
Facebook: / greatscottlab
Twitter: / greatscottlab
Support me for more videos: www.patreon.com/GreatScott?ty=h
In this episode of DIY or Buy we will be having a closer look at the Otii Arc product. It is a tool that can basically measure µA/nA and therefore calculate the used energy of a low power device. Since such a tool is super handy to have around, I will also try to create my own crude low energy meter in this video. Let's find out whether a Teensy microcontroller and an Op-Amp circuit is capable of measuring µA/nA! Let's get started!
Websites which were shown/used in the video:
hackaday.com/2017/12/22/coin-...
www.pjrc.com/store/teensy32.html
forum.pjrc.com/threads/25532-...
github.com/GadgetReboot/Proce...
www.analog.com/media/en/techn...
www.analog.com/media/en/techn...
ww1.microchip.com/downloads/e...
Music:
2011 Lookalike by Bartlebeats
0:00 Introduction (Why I need to measure µA/nA)
1:45 Presenting the Buy option (Otii Arc)
2:53 Intro
3:12 Testing the Otii Arc
7:01 Coming up with a DIY solution
8:44 Building the DIY circuit
11:12 Conclusion

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Опубликовано:

26 июл 2024

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Комментарии : 448

@greatscottlab 3 года назад

Just a quick information because viewers seems to feel like Buy won because the product was sponsored. That was not the case. When I do such sponsored videos I always make sure that I am allowed to say and show whatever I want. I tried lots of different designs for my DIY attempt but all of them were fails. For the video I picked out the most interesting DIY circuit. For me DIY was simply not the winner of this episode. So please stop saying that the outcome was influenced by the sponsor or that I did not try hard enough for the DIY circuit. Lots of stuff goes on behind the scenes of such a video production that does not make it in the final video. Thanks for reading this :-) Stay creative!

@I_killed_that_beard_guy 3 года назад

I trust you buddy.

@PrajjalakChattopadhyay 3 года назад

We use very sophisticated devices to measure nA, even pA in our labs, and those will cost you an arm and a leg. Sometimes they're cryo-cooled as well.

@DivyanshMMMUT 3 года назад

Brother Just keep up the good work If negatives are the drops then positives are the Ocean... I openly accept I was one of the person who commented that thing and now I am literally very guilty about that. I really respect you 🥺

@1900OP 3 года назад

If you'll make this attempt again, which I read that you might consider it in the future, I'd have a suggestion Place the first amplifier very close to the measurement point and shield the enclosure, so you get to reject some of those magnetic fields that are around , and lower the bandwidth of the amplifiers to the point where you can still see the desired current spikes using low pass filters. Higher bandwidth = more amplified noise. The first stage is critical, noise from that stage will be amplified by the other stages.

@lolmetauto4579 3 года назад

Just to be curious am i the only one who heard a pop at 2.41 and what was it

@bur1t0 3 года назад

Was almost expecting to see MarcoReps here in the comment section. Maybe nanovolts wasn't enough to summon him... perhaps if I say picovolts instead? Thermal regulation?

@moritzkoslowski5920 3 года назад

Best comment I have read this year so far 👍

@worstuserever 3 года назад

Marco was my first thought as well. A measurement like this would be almost too trivial for him; probably reach a dozen Keithleys, with precision to spare, without getting out of bed. I imagine the diabolical noise floor on the DIY attempt would prompt one of his trademark retching sounds.

@yanfishtwig2356 4 месяца назад

You have to say Yoctovolt 3 times in the mirror ..everyone knows that

@99Mrber 3 года назад

maybe take a look at EEV Blogs uCurrent schematics, should be possible to make a DIY solution woth this.

@onlyrgu 3 года назад

I was about to comment the same EEVlog uCurrent/Clone + a Good ADC is the winner!

@99Mrber 3 года назад

@@onlyrgu would not say that it would be better than the buy option, but maybe there would be better DIY relults.

@xani666 3 года назад

I mean it's not that expensive, you can just buy it

@koharaisevo3666 3 года назад

@@xani666 You can't, it's out of stock now.

@xani666 3 года назад

@@koharaisevo3666 Damn, Dave have been slacking!

@dj_paultuk7052 3 года назад

I once worked on an internal project where we had a small RF device that need to run for 1 year unattended with just a single CR2032 cell. The device would wake up every day, send an RF pulse with data and go back to sleep. Anyway we did a huge amount of testing with cells of differing makes. In the end the winner by far was Panasonic 2032 cells. From that experience i always use Panasonic button cells these days in all applications.

@greatscottlab 3 года назад

Good to know. Thanks for the feedback :-)

@AhmadLafi-TheFirst 3 года назад

Make sure to get your op-amps from a reputable source. Op-amps are considered one of the most targeted parts to be cloned due to their higher prices and difficulties to test their features precisely by hobbyists.

@iangoh8968 3 года назад

So close to 1.5k , keep going, great Scott

@pete3897 3 года назад

I built my own remote as well (a few years back) and I OR'd the 4 buttons into another digital pin using diodes. This allowed me to wake the microprocessor on the press of _any_ button rather than just one of them. A neat trick that might be useful to you next time :)

@jamesgoacher1606 3 года назад

:-) I like it when a plan dosen't always come together. :-)

@greatscottlab 3 года назад

It happens......

@sauritinfo2248 3 года назад

Your videos are always filled with the most expensive knowledge and instruments too😀😀😀

@mdroberts1243 3 года назад

Nordic Power Profiler II. Lots of similar products on the market. But for the cost this seems to have the best specs.

@JamesRuleGR 3 года назад

I've been using a few of these for work and I can vouch that they are extremely reliable and useful tools. Using them in conjunction with their serial function (as well as ability to use external serial devices) makes them excellent for recording events and their power draw on wireless devices. Pricey yes, but their value is incredible.

@nikolab5353 3 года назад

Great video as always!

@SirEngelmann 3 года назад

Your idea to come up with a diy solution for µA / nA measurements sounds pretty cool. I think that a low pass filter in the op amp feedback path would have made a significant difference in signal quality.

@TotallyNotJason101 3 года назад

I just waited for monday to come!

@TheBodgybrothers 3 года назад

Thick ropes

@MCsCreations 3 года назад

Pretty interesting project, dude! 😃 Stay safe and creative there! 🖖😊

@greatscottlab 3 года назад

Thanks, will do!

@susugar3338 3 года назад

Thank for making subtitle. Great video!

@greatscottlab 3 года назад

You're welcome 😊

@I_killed_that_beard_guy 3 года назад

As always nice and informative video.

@moonmatthew 3 года назад

Yes! Next great video to watch, thank you!

@greatscottlab 3 года назад

Thanks for watching!

@moonmatthew 3 года назад

@@greatscottlab You dont need to thank me! Your videos are Great!

@chethanr7670 3 года назад

Now its confirmed you and electronoobs are in very precise competition

@GabriCheckin 3 года назад

I like your "Stay creative and I'll see you next time!"

@greatscottlab 3 года назад

Me too :-)

@iwantitpaintedblack 3 года назад

@@greatscottlab Bleib kreativ, und ich sehe dich nnnnnnnaechstes maaal! - doesnt have the same ring to it :)

@mchammer256 3 года назад

I used a CR32 battery for my night vision.But that run on 2.7v so i put a resistor between positive from the battery to the night vision tube lasted ages before i changed it. As always grate vid keep the thoughts flowing till next time.

@ravishah6403 3 года назад

A video about raspberry pi pico would be great!

@greatscottlab 3 года назад

Maybe soon ;-)

@mnbvcx 3 года назад

Well, it basically just runs micropython, like the microcontrollers he showed in the Pyboard video

@mnbvcx 3 года назад

But I think the Pi Pico has a lot higer clock speeds

@markmacherey4744 3 года назад

it's the new dual-core Arm Cortex M0+ RP2040 running at 133mhz

@YandiBanyu 3 года назад

@@mnbvcx What interest me the most is the use of "Programmable IO"

@nickush7512 3 года назад

Another super video, thank you...

@Carlos-jv2so 3 года назад

Great video!

@sandeeps4726 3 года назад

Great Scott I felt that I am missing your projects these days like peltier fridge, Bluetooth speaker, portable monitor and stuff you did in the past

@tchiwam 3 года назад

I went through so many MOSFETs to find one with the lowest off current. That helped my battery life a lot.

@prassmancreations3168 3 года назад

Beautiful, now I can measure joule thief's

@bostedtap8399 3 года назад

Excellent, very interesting vlog. Thanks for sharing.

@mohamedhanon1874 3 года назад

You are on the right way to develop it , go on.

@69iqtutorial 3 года назад

Hiii, im happy that you finally posted a vid, by the way, what happened to mosfet drivers pt 2?? Pls tell , do we have to wait

@greatscottlab 3 года назад

Wait for it. It will take a while longer.

@69iqtutorial 3 года назад

@@greatscottlab oke

@AdriGomezD 3 года назад

Processing ❤️ Nice video

@michaelassouline667 3 года назад

The Nordic power profiler kit 2 (PPK2) is much cheaper at around $90 USD, and is also accurate down to the uA range with auto ranging. You would need a carrier board to operate it though. The Nordic PCA10040 will do the job and is also around $40 USD, so for around $130 USD you get a very similar functionality. The only downside is that you don't get a fancy enclosure... I have absolutely no affiliation with Nordic, but have used this at work and it did the job very well and with minimal setup effort.

@Delali 3 года назад

Stay creative and i will see you next time. always gets me

@__MINT_ 3 года назад

With opamp circuit, you can use a higher resistor value, for example 10k, which creates a 10mV voltage drop, when the current is 1uA. This way, by adding a multiposition switch to change the resistor value, crude low energy meter would work even with very low currents.

@eDoc2020 3 года назад

But then what happens once the uC switches on the LEDs and it starts drawing tens of milliamps? With your 10k resistor just 0.3mA would drop the voltage at the device to nothing. You'd somehow need to switch to a smaller resistor extremely quickly before the voltage drops.

@__MINT_ 3 года назад

@@eDoc2020 You're right. For such a case, it's neccesary to modify the circuit, for exaple use a mosfet instead of a resistor, but make it behave like resistor. This way, you can control it's "resistance" very fast. Of course you need some kind of feedback to know, what's the current resistance, and to control it properly.

@mdfyui8000 3 года назад

For the DIY/simplistic quality evaluation I would say the capacitor based method is the easiest way to validate at the nA/uA range (actually in the capacitor method we don't measure current, but in this problem you're not interested in the current but the energy). Prudent selection and identification of the characteristics of the test setup can product relatively useful results. Certainly it tells you about the 10k pullup that should have been 100k !

@ingmarm8858 3 года назад

There is a heck of a lot more to the OTII than measuring low currents (accurately and repeatably)! I bought 1 for home and two for the office where we also have the $35k N6705 from Agilent. I love the OTII, i just works and I know the results will be right unlike any homebrew solution. I've recommended it to a ton of friends and colleagues.

@Julian_Kulenkampff 3 года назад

Hi, thanks for making such good contend! You could have used an Transimpedance amplifier in a coockie-can. I tried this and was able to get gains from 10^6 or more.

@danpommerening3490 3 года назад

Yes Trans-impedance Amp. Ive used a Keithly pico-ammeter and it used a trans-impedance amp as its amplifier.

@iangoh8968 3 года назад

Yay new awesome video

@electronic7979 3 года назад

Very good video

@debuggers_process 3 года назад

I suppose you can use current mirror and try to charge up a capacitor of known value, measuring time interval with high speed microcontroller. But this current mirror can eat more current than you are trying to measure) Great videos you have here, btw!

@lordelectron6591 3 года назад

Hehehehehehh time to scale this into a powerful version And turn on my neighbours tv

@vgamesx1 3 года назад

100W remote to mess with an entire neighborhood's devices?

@evensgrey 3 года назад

@@vgamesx1 That's so 1980's. Atari came out with wireless controllers based on garage door opener (RF) remotes of the time. They worked well enough, but had the inconvenient property of a 2-mile range, so while any given set didn't interfere with each other, anyone in the general vicinity who had another set would interfere. (NOTE: If you have an older-model digital garage door opener system, get it replaced. The codes can be brute-forced in about 6 seconds.)

@lordelectron6591 3 года назад

@@vgamesx1 of course thats the fun And no one will ever know about it heheheh

@jhonny44444 3 года назад

@GreatScott! I think you can squeeze out quite a bit more energy from that cell if you use a 'vampire circuit' or Joule Thief. I think that circuit was first coined by 'bigclivedotcom'. It basically boosts the voltage of the cell to the desired voltage and keeps doing that until the cell is completely drained. (The cell voltage will drop over time and at a certain moment, the uC simply wont turn on anymore, even though the cell still has some juice left in it.) Would probably make an interesting video on its own! Cheers en keep up the good work!

@abelcino 3 года назад

Great Video! I was wondering if knowing that you have 2 states (standby and awake), can you use 2 different shunts? One big for low current and one small for high... Cheers!

@alexandrecorreia325 3 года назад

Hi. For very low current a good option is to go for a logarithmic amplifier. Make sure to choose a op amp with a bias current in the pA range (€€€). Cheers

@waseemh3863 3 года назад

I love your handwriting

@greatscottlab 3 года назад

Thank you! Cheers!

@martylawson1638 3 года назад

Pretty easy to measure pico-amp currents with a transimpedance amplifier as used in most photo-diode amplifiers. Much harder to then use the same amplifier to measure mili-amps. A log amplifier chip is a good compromise here. Forgot the part number, but it easily measured from about 10pA to 5mA. That said, an LM662 and a 10Gohm feedback resistor will let you measure 60fA currents :D

@tijojose6858 3 года назад

Bro i love u r videos .pls make a arduino uno based capacitance testor or an lcr meter

@diyrobotronics 3 года назад

Make some simple projects using raspberry Pi pico 😊

@greatscottlab 3 года назад

It is on my to do list

@VerballyCopulating 3 года назад

I second this request

@Derpuwolf 3 года назад

@@greatscottlab pog

@rockpadstudios 4 месяца назад

I worked for a year at a company that made remote controls, I still get the shivers looking at a remote, it was a crazy place to work. We did months (or it seemed like it) working on a Sony contract 8am to 12 midnight 7 days a week in a conference room. The AH gave me a $1250 bonus and a line in my performance review "he has potential with this company". Yeah he is stupid enough to work from 8am to 12 midnight. I did get Bluetooth Low Energy out of it and more experience with bare metal embedded systems. Just an FYI, companies making commercial products are on razer thin margins and can be sweatshops. I was surprised about IR communications and the number of custom protocols out there making universal remotes a huge engineering problem. I never would have guess money could be made in this niche market.

@mastrmarco 3 года назад

You are always very precise in your explanations, and you have created a very nice community for yourself, I hope to succeed one day too.

@greatscottlab 3 года назад

Best of luck!

@mastrmarco 3 года назад

@@greatscottlab Thank you :)

@andymouse 3 года назад

Go for It !...good luck.

@dexattech 3 года назад

Awesome 🔥

@sdp8483 3 года назад

With the Otii Arc not only are you getting good hardware but the software is also worth the steep price. I want one but it is too rich for my simple needs. Instead I got a Battlab One, not too expensive and the software is good. Gives you a good feel about battery life which is all I need. I believe EEVBlog has reviewed both of these instruments for anyone interested.

@olpqay 3 года назад

1:06 forgot the "h" ;) Keep up the great work :) Your videos always give me great inspiration!

@greatscottlab 3 года назад

Ohhh damn. No, the "h" is correct. I forgot to add another one behind the "A"

@olpqay 3 года назад

@@greatscottlab this is what i meant. I hope it doesn't bother you too much.

@williamcraig6377 3 года назад

Back in my Electronics Engineering lab, my professor always told me, look at all those antennas, referring to all the component axle leads. When keeping noise to a minimum, traces must be as short as possible with proper shielding. Part of what this commercial meter does would be have internal copper board layers while using ground planes externally. Board design and component selection is critical.

@VictorFS-eh3gr 3 года назад

Could you make a video about DIY linear motors? Do you think it'll be a good option for 3d printers? You're my electronics teacher in YT :D

@geirendre 3 года назад

Placing the opamp directly on the current shunt should help get rid of most of the noise. Do amplification closest to the source to avoid picking up noise before amplification.

@LoranDavis 3 года назад

The pens should charge appearance fees. Hehe. Great instructional content. Greetings from Newfoundland. Dorkily.

@nekomakhea9440 3 года назад

Early voltage reference standards used mercury batteries measured by high precision voltage meters as a physical constant, since mercury batteries can have low voltage dip for a given current draw. A minimal current draw to further minimize voltage dips was critical. It would be interesting to see if the Otii or uCurrent would be suitable to measure that voltage reference itself with low draw, but they'd certainly be helpful in testing volt meter circuits to minimize their current draw for this purpose. A project I've been toying with for a while is how to derive the metric units based on physical constant measurements in the home lab, and it's a tough chicken and egg problem given that most of the metric units are interrelated, and based on atomic clock definitions of a second; early scientists broke the egg by using artifacts instead for a reason. A mercury cell voltage reference is the easiest candidate as a starting point to break that cycle I've found so far, and then define the remaining units in terms of a mercury cell voltage reference.

@NorthernEwan 3 года назад

Otii Arc! Expensive but soooo good

@flo5091 3 года назад

What would you recommend for a hiking trip after the lockdown Thüringer Wald or Rhön?

@ChechenScienceAcademy0204 3 года назад

The nose you measure is the ADC noise from your ARM 12 bit ADC! It has no external reference pin on board. The ARM Cortex-X Microcontrollers have awful ADC. Only stand-alone ADC able to get rid of processor's noise. Plus a reference voltage for ARM ADC is a 3.3voltage of its power supply. Any decent op-amp with JFET inputs is able to amplify microamps. Wrap it in copper foil, connect to ground reference, give it a precision reference voltage and it will do the job perfectly fine.

@Pseudynom 3 года назад

1:06 You're missing an h behind the A.

@lucifersinferno3078 3 года назад

1.true 2.good eyes

@ELECTROGYAN 3 года назад

60th comment is mine ❤️ Great video Greatt Scott ❤️

@greatscottlab 3 года назад

Awesome! Thank you!

@mawoodmain 3 года назад

Try a joulescope for a more accurate and versatile measurement setup or a ucurrent from Dave Jones both great products Dave's is extremely affordable.

@robertbruce7686 3 года назад

Idea close to my raison d'etre but perfboard = not good low noise layout choice. Ground plane city, thick copper layout and an avalanche of decoupling cspacitors predicted... Excellent video!!

@gordonlawrence1448 3 года назад

There are tricks you can use to make an electrometer (a current meter for values less then a microamp). For a start you need a jfet input op=amp and you need to make it using "dead-bug" wiring techniques. That way you can get down to fA if you cool it down to -40C. I'm in the process of designing one of these for a DIY mass spectrometer right now. The LMC6041 is not perfect but if you want a FSD of 1pA it's easily good enough. The other point is to "spoof" it by using it as a split supply op-amp. IE design the circuit so it uses -3.3V for the ground rail and +3.3V for the positive rail. Also drift and offset can be dealt with not at the input (that would mess with the characteristics) but on the output between this stage and the next. One further point is do not use any kind of cleaner that leaves a residue or touch any of the components as that will leave conduction pathways that will drive you nuts trying to find and sort out.

@yanfishtwig2356 4 месяца назад

sounds fun both those are on my list and thanks for the opamp recommendation

@MuhammadDaudkhanTV100 3 года назад

Fantastic seekers

@BharatMohanty 3 года назад

I guess this may be the longest intro+pre intro video in this channel )

@greatscottlab 3 года назад

Possible......

@PhG1961 3 года назад

DIY of course !

@Simon-lj8bb 3 года назад

Wouldn't that be cool to have a diy or buy episode about a home thermostat. I would really like to know if I'd be better buying a new one or build one myself!

@serotonin336 3 года назад

Hello i love your videos 😍

@greatscottlab 3 года назад

Glad you like them!

@ch94086 3 года назад

Great topic! I've been wanting to try to make a cheap DIY current meter myself, even cheaper than the current ranger. One of the STM32L discovery boards (~$12) has an extra processor to measure sleep current down to nA. Instead of expensive precision resistors as in the current ranger, I was thinking of normal resistors and software calibration. I was thinking of using an op amp module. The current ranger uses cmos switches to select the range, but loses some readings as the software auto ranges. Since the op amp modules are cheap, another option is to connect the shunt resistors I'm series, then short out the resistor with a diode or mosfet when it goes into overrange. Using an internal power supply can give you more voltage drop range in the measuring circuit so you don't need to deal with such small voltages. Maybe auto ranging is the hardest problem. I'd say, give it another go on DIY current measurement. If you hit a problem, go back to the drawing board. It will certainly be educational.

@eDoc2020 3 года назад

The TI MSP432 launchpad also has facilities for measuring low current. These devboards are probably the best low-cost way to measure low currents drawn by projects.

@ch94086 3 года назад

@@eDoc2020 I haven't used the TI devboard, but the ST current measurement is integrated on the PCB so is convenient to measure processor power, but can't measure external power as far as I know.

@eDoc2020 3 года назад

@@ch94086 The TI board was set up so you could split it into separate interface and microcontroller halves. If you undo the jumper carrying power to the microcontroller half you can connect an external load to the 3.3v output instead. The problem is I couldn't figure out how to start measurement without an active JTAG connection, although it's definitely possible with the hardware. I might have had a bit of luck by starting measurement with the halves connected and then undoing the jumper, but I don't really remember. Unfortunately my board is no longer functional so I can't go back and check.

@wesleymays1931 3 года назад

Using the Otii Arc in that second mode reminds me of a Source-Measure Unit (SMU), which would explain the high price point, those usually cost *thousands* of dollars.

@yanfishtwig2356 4 месяца назад

indeed it describes itself as a 2 quadrant smu if i remember correctly

@jozkokalny654 3 года назад

Hi, i am currently making a project where i need to measure a current of a small board, i am currently ursing INA219 for this task, but my problemi s that the readings are really unstable if the motor is spinning without any force on the opposite end stopping it, is there any way to fix this either by using different board than INA219 or in code, ty in advance

@bkmaxinewsodia 3 года назад

Amazing

@proller14 3 года назад

2 thoughts: 1) There's a good piece of software, called SerialPlot, which in this case of 'graphing' is a bit easier to use. 2) With the mentioned shunt resistor measuring, you forgot to mention that there's a voltage drop on the resistor, which will result (assuming a fixed supply voltage) a 'voltage drop' on the measured device' supply. So this way, the supply voltage of the device can vary based on the current flow, which can lead to even operation fails (by alternating the actual supply voltage) if the current is high enough.

@arnaud7671 3 года назад

5:20 looks like the infrared signal is visible through the power consumption. Nice example of a side channel attack.

@eDoc2020 3 года назад

I've actually used this to measure the signal sent by remotes (both IR and RF) without needing to have a dedicated receiver.

@lukafricker 3 года назад

You should try out a High Gain Instrumentational Amplifier from Analog Devices. Combine that with a proper ADC and you should be good to go for a diy Version :D

@ha23456thtjh 3 года назад

Nice work thank you 👍 I hope you make a video to how build 4to 20 ma generator for analog control by using Arduino

@atose_offline5463 3 года назад

Hi, for microcontroller I use MSP430 series by Texas Instruments (MSP-EXP430FR6989), and for current shunt sensor INA186. A greeting

@cheaterman49 3 года назад

Hmm! I'd love to see you revisit this with PCBs from our favorite supplier, possibly using some of the ED tricks the commercial product did (massive holes or slots for isolation etc). There has to be a way to make the output less noisy without breaking the bank? Of course the PCB is gonna take some time to design and route but it's not that big of an investment? Our favorite PCB supplier drove the cost "down down down" :-)

@richardvanrijn3982 3 года назад

You should try the INA212 for the amplification it is designed for measuring low currents

@electromatic138 3 года назад

let's get started

@TarantPavel 3 года назад

I used current - voltage converter circuit to measure reverse pn junction current in liquid nitrogen temperatures in ranges of 100s of femtoamps 35 years ago. There was an electrometric hybrid opamp with resistive network in feedback circuit and the result was pretty satisfactory even concerning noise. I would do something similar to measure such a low current consumption nowadays.

@greatscottlab 3 года назад

Thanks for the feedback :-)

@TarantPavel 3 года назад

@@greatscottlab to make it more clear - i would suggest to use opamp to sink current flow to virtual ground which allows to use much greater resistance to determine the desired voltage drop thus overcoming the need to amplify uV voltages

@Chris-ut6eq Год назад

I think with better DIY component selection, perhaps based off what the bought option used, and other DIY/open source options, you could measure in the 100s of microamps level and perhaps lower. This was a good infomercial for the Otii though. Nordic semi has a power measure device in the 100dollar/euro range and that would be a better option. Andreas S. did a nice video on nordic device and a few others.

@minusharma1738 3 года назад

10 mins 1.6 k views very active community 👍

@ping170 3 года назад

Any chance that changing the shunt resistor on an INA21x like the one in your previous energy meter could do something useable ?

@VoltZero83 3 года назад

I once watched a movie about designing low battery consumption circuits, and the circuit itself was powered by a capacitor while sending the signal, and the capacitors were charged with low current between signal transmissions. This resulted in the battery being discharged with low current.

@gabrieldai88 3 года назад

I want to know if you can read milli Amps with a DIY version using Arduino, or it is too slow?

@bringdamage1396 3 года назад

I love it

@davidkclayton 3 года назад

I would do a logic controlled variable shunt with comparators that way you don't have to read microvolts

@ikemkrueger Год назад

You need a self correcting feedback loop circuit. Some circuit like the circuit which is used to calibrate crystals for timers.

@514_cricket 3 года назад

Hey, what if you would just switch the shunt resistor value to higher one or even place a few of them in series? Voltage drop would be higher, so easier to detect, and since we are talking about analysing a super low-current device, I don't think that it would effect it a lot. You could even turn up input voltage a bit to compensate voltage drop across the shunt.

@indian.techsupport 8 месяцев назад

pretty close to the µ-current, but fair, dave is a really good designer

@alzoha1267 3 года назад

Big fan from India❤️ Please review the new raspberry Pi pico please

@greatscottlab 3 года назад

I already ordered 2 :-)

@alzoha1267 3 года назад

@@greatscottlab 😋😀

@theanalcolico 3 года назад

Have you considered using an already available ultra low noise and analog to digital converter combo such as the HX711 usually used in combination with strain gages for measuring weights? I might recall seeing you using one of those in this channel. It is basically an instrumental amplifier combined to a 24 bit ADC. I'd recommend that before jumping to conclusions. You might get interesting results ( maybe not, idk :D). I personally used it in a few projects and just remembered how stupid sensitive it was. Of course it will get a lot of noise too but for just a couple bucks, might be interesting a try. See ya

@greatscottlab 3 года назад

Tried it. Did not deliver decent results.