ฝัง
- เผยแพร่เมื่อ 8 มิ.ย. 2024
- Most of our modern processors and sensors need a stable power supply of 3.3 volts. Some older chips require 5 volts. And a raspberry pi needs nearly 1 ampere while an ESP in deep sleep requires only a few microamperes. Sometimes the current consumption is quite stable, and sometimes we have big current spikes like our ESP chips during Wi-Fi transfers.
- We will discuss the two different principles for control of voltage: Linear and switching (buck, boost) regulators
- We will find out why linear regulators efficiency often is bad and where this fact is not significant. We also look at the thermal design and how it influences maximum current
- We try to understand why switching regulators have higher efficiencies and can be built smaller for high currents or higher differences between input- and output voltage
- We look at the output ripple and on other high-frequency signals and where they can hurt
- We will test how the different regulators behave when your processor is in deep sleep
- Finally, you should be able to make the right decision for your project
-And you should be able to do a small talk using all the buzzwords mentioned before
ERROR CORRECTION: Low Quiescent Regulator is HT7333, not HT7111. Sorry.
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ERROR CORRECTION: Low Quiescent Regulator is HT7333, not HT7111. Sorry.
Prison time for such blatant mistake ! Oh wait you are not a surgeon :D
Another small omission creeped in at 9:51. It should be 24C over ambient temperature. So 25C ambient + 24C regulator ~50C total.
Hi 7133 with 24v input voltage and 2.5 microamps Quiescent is better than 7333
Unfortunately, the HT7133 will not work with most icrocontrollers as it supports only 30 mA
The Maximum output current for HT7333 is 250mA. As the ESP32 has spikes of current that varies from 300 mA to 400 mA, I think that one good alternative to this is the LT1763-3.3. The quiescent current of LT1763-3.3 is a bit bigger (30uA) but it can delivery current up to 500 mA.
What do you think, Andreas?
Wow! What a comprehensive coverage of regulator selection and application. I’ve been in the electronics business for 35 years and never have I seen so much valuable content in 22 minutes!
Thank you for your nice words!
Thank you for a comprehensive overview of the major differences of these regulator types. Every time I watch your videos I realise how much more I need to learn :-D Keep up the great work Andreas.
You are welcome. I hope this is encouraging ;-)
Excellent video again. I got a little muddled up at the end when you were summarizing the quiescent currents and the devices. For my head there were too many numbers to keep track of. A table would have been superb. No matter, this was super helpful for me and I really appreciate your efforts. I recently did a project using a MCP1703A. It has a very low quiescent current of 5uA.
You are right. A table would have been a good idea. Maybe next time...
Clear and concise, very Swiss! Thanks Andreas.....
You are welcome!
Super useful tutorial both in the telling & in the interesting & useful comments discussions as I am currently struggling with creating a low voltage & low quiescent currents along with noise suppression for a project. Thank you for sharing!
You are welcome!
Thank you Andreas, recently I was graphing heat dissipation by Buck converter powering from 12v Battery to Raspberry Pi. And at right time you uploaded the video. Now I have understood many important factors for selecting the regulator.
Thank you for your feedback!
Thank you for your posts. I enjoy just listening to them at my bench or desk. Keep them coming!
You are welcome!
Really great video to refreshes my half-learned, half-forgotten knowledge from my electronics course 10 years ago :D
Glad you liked it!
Thanks for another excellent video. I am a retired Mechanical engineer so my exposure to electronics, up till now, has been limited. Your videos are well done and I feel that I am learning lot from them.
Good to read. I had to learn some "mechanical" stuff when I bought my CNC mill. Was not easy...
Thank you Andreas! You are making the world and the people better every day
Thank you!
One of the best videos you've ever done. Very detailed!
Thank you!
I am amazed at how informative these videos are. Thank you for sharing!
Glad you like them!
While a bit crude, you can usually find better quality switching regulators on old PCBs. I've had better results than the cheap modules I've bought before. Things like old wifi routers usually use one or more step down supply circuits that are designed well and they don't interfere with the radio circuit on board.
I've also found a few Buck-Boost SEPIC converters on old wireless keyboards and mice. When I'm salvaging these circuits I usually check them beforehand to see the output and the basic topology. Then I mark an outline to cut and use metal shears type scissors to quickly make my own modules from the original PCB. I think that's a bit crude for a Pro EE like Mr Spiess, but for the beginner or hobbyist it's a handy way to learn about different circuits and do some real world recycling ;)
-Jake
I am also a maker and do not build things to sell ;-) I like your idea.
I tought physics for a while and you are definitely my reference. thanks so much.
You are welcome!
I'm very impressed by all of your videos. Outstanding informative, very didactical and very well structured. Answers to a lot of questions I had or never had, but should have had :-) Very inspiring. Please keep on going like this. I became a patreon of yours.
Thank you for your nice words and for your support!
Danke für deine tollen und gut verständlichen Videos. Hab schon sehr viel von dir gelernt!
Vielen Dank für deinen Support!
Finally found the video after 30 min searching. Yesterday I watched this without being logged in and it did not show in the history, but forgot the author's name. I enjoyed the video - informative and entertaining at the same time. Thank you!
You are welcome. Glad you found it.
It's amazing how much you can cover in 20 minutes. Good work.
Thank you!
Thankyou so much for your time and eplaining so clearly these topics.
You are welcome!
Very well explained, Andreas. This is one of my favorite videos to start learning microcontrollers!
Thank you!
Enjoying your channel a lot and thankful your English accent is heaps better than my Swiss mate who has lived in Australia for nearly 30 years..... :)
Thank you!
Another great one.... I’m learning tons on the Channel! Thanks
You are welcome
Spectacular as always! Looking forward to the box design and print video.
Thank you!
Hey Andreas, you just got this video mentioned on Hackaday. Good job and hope your channel continues to grow. May the Swiss accent keep on going!
Thank you for the info. I did not know.
Thank you so much! You are one of the most valuable persons who can change people's value.
Thank you for your nice words!
Very nice videos sir...from the philippines here...🇵🇭🇵🇭🇵🇭
Thank you!
Beautifully illustrated.
Many thanks!
Thanks for this video. I thought my wireless doorbell fried when I changed batteries to step down regulator and transformer but was the noise which blocked the signal! Now it works with a regulator ic. Thanks!
You are welcome!
Another great instalment and even better Building on your previous posts. You have to listen out for the new information and then the light bulb clicks on😋.
Clear concise = Andreas Spiess
Thank you very much!
Hello Andreas, thank you for this very informative video! This is truly a subject that interests all makers. A little more information on buck/boost converters would have completed the topic. I personally like to use them to make projects that can take a range of input voltages. Thanks for all the time you invest to help us all move forward and I'm always looking forward to viewing you latest video on Sunday's. 😀
You are welcome. I already abused my 15 minutes rule ;-) Maybe in a later video.
Danke vielmal, Andreas!
Gerne mehr von solchen "basics" Videos.
Viele Grüsse in die Schweiz!
Bitte, gern geschehen. Mal sehen, was sich dazu noch eignet. Ich möchte nicht etwas machen was es schon in Duzendware gibt ;-)
excellent video, as always. big thumbs up from your neighbour in Austria.
Thank you!
Thanks for sharing 😀👍
You are so simple in your examples, I like that 👍
You are welcome. I always try to create understandable videos. Thank you for confirming that I got it right!
10:25 - "You see?! Reading datasheets sometimes is a good thing. Before the magic smoke escapes or after it. Depends on your personality" :-DDDDDD So funny!
I scrolled down as soon as I heard him say that and saw your comment...You beat me to it! lol
Thanks for making these videos, they are very interesting and thanks for sharing your knowledge. :)
Learned a lot from this video. The Swiss Government should hire you to be their online TH-cam Electrical Engineering teacher. Are you a former EE instructor ? Your presentations are very good.
No, I am not an electronics instructor. But I did some courses at Universities in other topics
Very nice! Clear and concise.
:-)
Important! learned a lot. Thanks.
By the way, at 5:00, I felt that you treat your components like some life forms. And I agree totally, every component deserves it's/his/her right to life:)
You are welcome!
Pledged. Excellent channel helping my MFA computational art at Goldsmith s London!
Thank you for your support!
Informative AND humorous! Thank you.
You are welcome!
Great, informative video! As usual for your channel!
Thank you!
Awesome video Andreas! Really learnt a lot! Thank you!
Happy to hear that!
...because I can not watch them die in front of my eyes ... instant like, kind sir!
Thank you!
Clear comparison and nice video.
Thank you!
Fantastic video Andreas. Maybe your best yet. If felt like the longer format allowed you to be much more through.
Clearly you put a lot of time into creating this one (even more than usual). Thank you.
You are right concerning time ;-). You are welcome.
Thanks for another great informative video Andreas. I favour the MCP1702 series LDO linear regs, especially for deep sleep battery operations. Key feature is the 2uA quiescent current. The 3.3V version has a drop out voltage of 525mV which isn't too bad.
Thanks for your feedback.
This video reminded me the Electronic course in my University. Very insteresting!
Thanks!
Great intro to powering projects.
Thanks!
Hi Andreas, great work as always!
Could you name the tiny BOOST converter PCB module with BC035 making on it that you used at the end of the video .. which BOOST converter IC does it use?
What about the M8-03 BUCK converter module you showed on ALiExpress? Which IC does it use?
Thank you Andreas for your clear explanations!
You are welcome!
Great video. You probably knew I was going to say this ;-)
Btw, you have a Prusa MK3 ! Omg, I'm realy getting jealous now. I'm already saving for this.
Yes, I have the new Prusa. My old one had intermittent problems and I read a lot of good stuff about Prusa. When I got on his page, he just released the new model. This timing enabled me to be one of the first who ordered one. Not cheap, but I am so used to 3D print...
wie immer ein exzellentes Video.. weiter so und vielen Dank für deine großartige Arbeit.
Bitte, gern geschehen
Another excellent video. Thanks Andreas.
You are welcome!
This is great for constant current applications. Would love a video series for data channel conversions and necessary side effects. Been having issues driving LED strips and either dropping 5v to 3.3v data channels or vice versa.
If you are talking about level conversion between 3.3 and 5v: There are many small boards available which do exactly that. From 5 to 3.3v only you can use a voltage divider.
excellent informative video! great channel! thanks for al the information!
You are welcome!
Very nice. Deep sleep miniatures, I can see a use for those, wake on demand, wake on request, wake and upload, wake and broadcast, wake and receive.
Great Video; the housings you made for your instrument displays, were exceptional. Not only are they easy handy, they look great, nice tools. I could actually see being able to combine them like legos, and serve a function. That would actually be kind of cool. One of your blocks could be a power supply, snap on an op amp, or any of so many nice little circuits found out there. Pop on a strob. a VU meter, a light detector, a mic module with a pre amp. Some of the modules could be lights, speakers, both combined. every module with some sort of indicator or read out, Of course they are kits, you have to build yourself. Finished they are tools for testing. bread board circuits inside, easy change and test similar components.
Just Tripping out on your electronics, which deserves recognition for ingenuity. imagination. practical application. clean math with clean parts, and a clean work area with all the testing equipement.
That would be a great job, designing testing equipment, that gave the user the feel of real power, flipping switches, fine tuning, mode selecting analyzing power. signal generating, analyzing zoom in, out red light flashing power. I want to build .
Fun hobbie. I created an under sea world with green and blue LEDs that happened by accident, I saw a concept, and now it's an environment.
Maybe you start to build your own system with such boxes? I made a video on how to design them quite easy...
@@AndreasSpiess Nice. The guys at the electronics store where I get a lot of my supplies sell the printers, they have one set up, and I always have to see what they are up to. I would sure like to have one.
another exzellent presentation. I really love watching you as you really make things easy. Can you also post the types or AliExpress links of the regulators you measured. Will make live easier if I need one to order
I think I placed the links of the two switches. the others can be found by entering the part number.
Sali Andreas, love your Swiss accent! I also have not been able to get rid of mine. As long as you call the meat on the plate not like the timber no worries. But the FBI is like ei so is the quiescent current. English is not regulated like German. Downunder we drive on tyres while in the US they use tires. There are tongue breakers. California has Yosemite and in the land of Koalas we eat Vegemite, both same ending but different pronunciation. Acronym abuse gets one confused so in our ham radio club ce hand each other upper sideband siticks!
Thank you Andreas! I'm issuing a Winter Topic Slide Warning: For projects that are 'mostly mains powered', I frequently use microcontrollers together with an added 18650 LiPo battery as an uninterruptible power supply. The use case I'm describing is not very different from a solar power use case.
I found that a combination of a charge controller module, a buck-boost module, and a pair of diodes works well enough for this, but it is not efficient, it is fairly expensive, and it doesn't seem to maintain the battery very well.
Now, I imagine this to be a very common use case, but either there are no such power management chips, or I am incompetent at searching vendors' parts catalogs. In all your searches for efficient parts, have you or one of your brilliant fans come across an efficient solution to A) power a microcontroller, B) maintain a correct charge on a 1S-3S LiPo pack, and C) efficiently manage the power transfer between the external supply to the LiPo and back?
I still have this use case on my list for solar. Maybe it will become one day a video...
Hi Andreas, My project use 3 AAA battery, so I need a regulator to power the Microchip PIC at 3.3v. Quiescent current is mandatory for extend battery life. Micro most of the time is in sleep mode and it consume less than 1uA. I used the Microchip MCP1810 LDO. It has only 20nA!!! Another plus is that when input voltage is less than 'drop out voltage' input is shorted to output (LDO is excluded); so I can use battery down to 3v or less.
Hi, Andreas. During 17:58 while you were talking about measuring current, I see your probe is actually measuring voltage?
Very useful ! Thanks !
You are welcome
Hello Andreas--love your channel. I am wondering how you configured your Electrical Parameter Testers you use on your lab bench.What are the plugs all for. Thanks Stan
Never mind-I just found the build video Stan
My fave buck regulator it's the TSR2433, I like the single package so and three pins so less chance for me shorting it out on something!
Nice product!
Always a pleasure
Thank you!
Another great video.
:-)
Thanks for the video. I love those small switcher modules, but have never verified the efficiency and do not have the instruments to measure the ripple.
If I understand correctly, one could put and LDO after the switcher to smooth out the output. Could you tests this setup? Say and HT7333 following the switcher module set at 3.5v?
Sometimes this concept is used. But this is a niche. I will use it if a project requires such a design
Hey Andreas! Thanks a lot for your work. The black parts boxes stacked near the wall look like something I'd like to have. Do you have a link to order them from AliExpress or similar?
I bought them at our local Aldi store because they are cheap there...
Another view of the inductor and capacitor in the switching circuit is as a low pass filter "smoothing out" the AC you are making into DC by turning the switch off and on (vs the energy tank explanation :) )
I agree.
I love your videos, than you very much! :-)
You are welcome!
Great video!
:-)
Very nice video!
Thanks!
Thank you very dear
You are welcome!
wow Andreas, This video was amazing, exactly what I was looking for and you explained everything so clearly for a beginner like me. I really do appreciate these videos, as does everyone in the esp8266 community. I do have a question for you: would the buck convertor's inductor interfere with the esp8266 wifi signals? Also, do the buck converters need capacitors? Chris
I have never donated or paid on a patreon before but I think that I will support you so that you can continue making this type of content.
Thank you for your nice words. Buck convertors usually do not interfere too much on 2.4GHz. It is always good to have a capacitor between VCC and GND of an ESP8266 because it draws a lot of peak current.
Is there a way to filter out the high-frequency ripple created by the switching converters? Maybe decoupling or smoothing capacitors of various values?
These power supplies already have capacitors and usually also inductors built-in. You always can increase their size. But for really "quiet" power supplies most people use analog designs.
Very good video !
Thanks!
Very good video. Personally i try avoiding variable converters because i have had problems with bad trimpots that throws the voltage out of the set value. I stick to fixed regulators.
I agree.
God I love your videos so much!
Thank you!
You should consider output voltage ripple in quiescent mode. As the controller usuallys switches from discontinious current mode to pulse skipping when there is nearly no load. This may result in significant higher ripple on output, which may not fit your requirements anymore or even can trigger a brown out detector of a micro controller. Allways remember to measure ripple voltage as close to output caps as possible! Even the ground wire of the probe can become an antenna at these frequencies...
This was more an overview video. So I had to stay at the surface. Anyway, I recommend for the ESP projects relatively big capacitors which might help in this case.
Hi Andreas
Thanks for video. I was wondering if you compare between step down buck converter characteristics such as xl4015 and lm2596.
Thanks
I am not sure if I will do that because they are quite big and usually, we do not need the currents they provide for our small devices.
Great video. I've learn so much from it. What do I have to watch out for step up regular? I'm making projects with Raspberry Pi and it take 5V, but most re-chargeable battery is 3.7V.
Just look out for a regulator with 5 volt out and 3 volt in
Klasse Video!
Danke!
another great video
:-)
Andreas. Do you have a video on the wiring of those little meters? What is the green banajack wired to - and what is it's purpose? Thanks !!
I plan to do an instructable.
What about employing one or more smoothing caps across the output to deal with the ripple from the switching converter as you would in a mains supply PSU?
I love your sense of humour too Andreas, it's a huge bonus to your videos.
Caps are usually good;-)
Excellent
:-)
Excellent video as always! What if saving money is not the primary goal? Instead if we wanted to focus first on efficiency and then on a smooth output with low noise? How can we find such?
As mentioned, it depends on the input voltage. For a Lipo and 3.3 volts, I probably would go with an LDO. Switchers are always the second choice for me because of ripple and noise. I only use them if I need.
Maybe connecting a switching regulator with a voltage slightly higher than the output to an LDO? This would be quite efficient since the LDO only has to drop a few millivolts and smooth because of the LDO's noise rejection. And for a LiPo, the best would be a buck-boost converter since, with an LDO or buck converter, the voltage must be higher than 3.3 V for the MCU to operate properly. Better use 2 smaller cells in series and a buck converter. And probably some EMI shielding (a piece of aluminium foil should do).
Hi Andreas,
Thanks for this great video!
What do you think about logic level converters in this context?
To give you some background: I am building a LoRa beehive scale using an HX711 for measuring the weight and a Hope RFM96 for LoRa transmission, together with a bare bones Arduino. The device will be powered with a 3.7 V LiPo battery (4.2 V fully charged), which is too much for the RFM96. Also, I found that the HX711 needs a steady voltage, as the output varies with varying voltage (I tried 3.3 V and 5V and the values were quite different). Any ideas on how to provide the Hope RFM96 (and HX711) with a steady 3.3 V?
I think I made a video about powering of microprocessors. In your case, an HT7333 would be a good choice.
@@AndreasSpiess Thank you Andreas. Just found your video #091 where this is explained.
Hi,
I really enjoy your informative videos and your attention to details. I want your opinion on S7V8F3 Pololu. I ordered ESP32 devkit OEM one and it came with AMS1117. Battery timing is poor and i intend to replace it with this module.
I do not know this module.
Hi, I am searching for a regulator circuit ic for lowering the voltage from 27 to 24 volta at 15 amperes. I am not able to find any which supports more than 8 amperes. Example LM2576 ic supports max 3 amperes, i need one which can use 15 amps. Please suggest.
There is another very simple solution, a shunt regulator, such as the TL431. It is "like" a super Zener diode (in reverse) and in PARALLEL (not in serial) with the "load". It can be adjusted to fit any voltage from 2.5V to 36V (without exceeding the voltage of the source, it is not a booster), with ZERO drop out voltage and requiring just 1 mA to work (in parallel with the amperage delivered to the load) (You can "typically" have it to work for a current as low as 400uA, but it is preferable to have 1 mA to be "sure"). So the power dissipation, for your example, can be as low as 0.001A * 10V = 0.01W. The TL431 may be delivered in a TO-92 case (looking like a discrete BJT), and you only need to add one, two or sometimes three resistances to make the required circuit (plus connectors). Its cost is really low (0.06$CAN at Amazon). Its SPICE model is available with the free version of TINA (distributed by Texas Instrument) (Just be careful, BEWARE, TINA does not use the standard TO-92 numbers for the pins, mis-wiring the TL431 is a huge possibility, consult the spec sheet and wire accordingly, not intuitively). If it is becoming warm to the touch, you probably have miss-wired it. The major problem, in the actual case, is that even without "load", 1mA is a large "quiescent" amperage. So we would have to disconnect the circuit, somehow.
Thank you for the info. For small currents a good idea. The TL431 has to "eat" the whole current if no load is attached. And the resistors have to be small enough to provide the voltage at max current.
Super tutorial again thanks.
I am currently testing low power applications using €1 Attiny85 + p-channel Mosfet as low quiescent current interrupt driven supervisor on regular 3.7v LiPo. The Attiny/Mosfet powers up Espressif based ESP-Now, LoRa or LoRaWAN MCU's via LDO depending on the application. The Esprdssif chip triggers it's shutdown and Attiny's deep sleep. Looking at Attiny + software serial for LoRaWAN frame count for fast ABP transmits.
Your thoughts?
Sounds like a good solution for deep sleep. And the ATTiny for sure does not need a lot of current. I would like to compare this concept with the Low power unit of an ESP32.
Andreas Spiess For sure, me too. The large LiPo with no parasitic regulator on the Attiny is the lure. All Espressif chips currently need LiFeS04 or a regulator I believe.
I see...
Excelent
Thank you!
Nice video
:-)
Hi Andreas, nicely done video. I believe I saw a USB isolation board at 18:02 (bottom right of the video). I am assuming you use it for data logging to a computer or laptop. I want to use it for the same purpose in order to use a USB oscilloscope with my PC. Can you share your experience about it? Or, perhaps you can make a video on using this isolator with a USB scope?
I think I already covered it in one of my videos. But I do no more remember in which one. Using this with a USB oscilloscope is a good idea.
Great video! I wish I would have watched it before I made the experience that my 1A regulator overheated already with 0.2A. There are two issues for which I would like to see more info (maybe you have it already in another video). Which capacitors (size and type) should be used with the regulators? Which temperature is acceptable i.e. in a small case? I know the datasheets have some information about both these points but I am sure you have additional practical advice. Thanks
We also use the data sheets for our work. Not a lot to add.
To avoid that the ESP does unwanted resets I add a 1000uF capacitor. Maybe you watch my deep sleep video if you are interested.
@@AndreasSpiess Thanks for your fast reply. I had a problem with an Arduino Mega 2560 Pro Mini with USB power supply. It stopped working after a few seconds. I added a 470uF capacitor and all worked fine. I was surprised that the USB port from my expensive ASUS Motherboard was not "good enough". I watched already your deep sleep video. Interesting!
If you were reducing from say 12v to 3.3v, but needed a smooth supply, would there be any benefit to taking the voltage down to 5v with a converter with a decent smoothing cap, and then using a linear regulator to take it down to 3.3v to give a smooth output without as much power loss?
In very rare situations this might help.
Excellent video, thanks! Can the buck regulator HF components be mitigated with additional capacitors or maybe ferrite beads?
Both would help for the output ripple. For the emissions I am not sure. Maybe a metal can helps there. Or distance between the regulator and the antenna
Switching noise can be suppressed. Google for snubber circuit. With ferrite beads watch for saturation.
Andreas!
In my quest to build an Adafruit Huzzah 32 set-up for some sensors reporting via WiFi/MQTT every 10th minute (ie.. more often than yours :)), and being solar powered so it can run for ever, I have followed and learnt much from many of your videos. Revisiting this one, i can happily report that i am ALMOST there. I only want to use one battery, so it goes on the MPPT solar charger. I then connect the load from it to a buck-booster and power the Huzzah via 5 V USB. It is weirdly enough the only way i got it to work (to many components!). Problem: i must now turn off the booster via its Enabled pin (as youre talking about @ 18:50), but how can i then switch it on from a completely un-powered Huzzah? I ask you this: if i put a big capacitor on the USB of the Huzzah (which is in deep-sleep, time wake up), will that enable me to enable the buck-booster just long enough to switch itself on, and thusly power the Huzzah? Is this safe? Do i need a resistor somewhere to limit current?
And thanks for your videos again. Wonderful!
/Axel
I would make sure the Huzzah is never unpowered. This should be possible in your design if you have enough power. You could measure the battery voltage for example.