Please note that eFuse also has a second, very different meaning in electronics: a One-Time Programmable memory bit integrated into the silicon die, for example you can permanently write protect or even read-protect the memory inside microcontrollers, game consoles like Xbox an PS have eFuse banks in the CPU to prevent firmware downgrade, etc.
damn you got me there! I was about to say the same thing! XD Yeah, those consoles do use eFuse to prevent downgrade and in the case of the Xbox 360, Per-console CPU keys are also stored on the eFuse.
You have just solved a design problem I’ve been dealing with for almost a year!!!! Thanks you so much. I had no idea that these chips existed. Dang. I’m too old. Got my Electrical Engineering degree 46 years ago. Used a slide rule. No cell phones and no HP calculators. Oh, well. I will be using JLCPCB and building a new revision of my board with these efuses on them. Now to study the data sheet. GREAT SCOTT is really great!! Thanks for a really great video!!
They have been around in a single chip for decades but only last 10 years been small enough for things like Smartphones, Portable Game Consoles and high power compact chargers
The best protection for your circuit is when you accidentally soldered same-gendered connectors on both device and supply side. Can't smoke any electronic if you can't power it in the first place.
Excellent. You have revived my interest in hobby electronics. I've lost count of how many times I ruined projects but not taking care of this stuff! Keep up the good work.
I remember building one of these using a MOSFET and two transistors - It initially was meant to be a low-battery cut-off, but wound up having good short-circuit protection capabilities...
I love your videos. They are just clean, concise and detail oriented. I'm always looking forward to your videos to learn more. Keep up the great work Mr.Scott
I have been designing these into my designs for years - eFuses offer a lot of control over the behavior of circuit protection. You do have to be careful because you can induce various issues like oscillations and SOA violations that get ugly quickly. Pay close attention to both the circuit design AND the PCB layout
@@henrikemppainen2511 'Safe Operating Area' generally speaking, it refers to the parameters that collectively will heat up the silicon die on the MOSFET switch. The part is damaged at a certain temperature and the designer needs to manage the device well enough to stay within the safe operating temps. It can be tricky.
Very cool. There might be a big market for eFuse demo boards with trim-pots for adjusting voltage and current control, and Pheonix connectors so people could wire these into their projects. Post-assembly powered functional testing would be a great application. I can't tell you the number of times I've seen small circuits boards scrapped during manufacturing because there was a short somewhere that damaged something on first power up (during functional testing). By controlling the power to the UUT, these could even protect against damage to other components in a system or the test equipment, to some extent.
Idk why but your segments where you write and explain really sink in more mentally than if you were to just be talking. It's partially what keeps me engaged in the videos 👌
What I appreciate about this post is the suggestion to take the circuit apart right after the work is done. Not to enjoy the experiment too long, but to move on directly to the next one.
You’re amazing, thanks for sharing all this knowledge. I’m a hobbyist and you make easier for all of us to understand and apply the concept to our projects. Thanks!
Commodore 64 has a notoriously bad PSU with its 5V DC overvoltage mishaps. This would be a great project to do an overvoltage protector for it! Nice one, "Scott"!
For reverse voltage protection just pop a full bridge rectifier IC before the eFuse and boom you have circuit working in normal and also in reverse polarity. The 1.2V drop might not be goos though.
Great, maybe this is my next solution, working with colleagues capable of breaking anything they touch... One thing I've learned at work is: _Regardless of the amount of protection I put in my circuits, my (non-tech) colleagues will always find a way to destroy them..._ They have: - Put a powered PCB on top of a metal table, during testing... - Ripped a USB-B port of my board, trough hole version... - Reversed the polarity, on a prototype in which I told them to wait on me before powering it... - Used the wrong adapter / battery / voltage... - Used it outside without proper watertight enclosure... - Put multiple PCB's on top of each-other, while powered... - Peeled of a 0402 capacitor, because they thought it looked like a dirty breadcrumb... - ... I would dare the military to lend them one of their armored vehicles, for testing purposes. My colleagues would probably break it within the next 5 minutes, by just looking at it.
only at low currents; @ 500mA it will be at least 0.4V and if you have already a supply of say 3V3 then you will get 2V9 or less to supply you circuit - it simply might be too low. And that eFuse @ 500mA will have a drop of just ~ 45mV
Im not sure if you have mentioned this before but another method of reverse voltage protection is a bridge rectifier circuit. Then no matter the polarity, the circuit still gets the correct polarity at the sacrifice of the small voltage drop of the diodes.
@@markderlo212 "extensive" is relative to the project. Most diodes I have used in this exact scenario have a 0.7 Volt drop. That was no where near "extensive" for my purposes.
I really appreciate your videos. Even when I don't feel like going to the bench for a week or two, these are so easily digestible and are perfect small applications I can make use of later. Thanks!
Thank you for sharing your vast knowledge! My biggest problem now is geographical location, since I now live in Brazil (6000 miles away from my native England), there are very few components available here, you need to order from China or buy in quantities of thousands from Farnell, Mouser etc!
AWW MAN Electronics basics Love the basics Again here commenting just after getting notification by leaving my all work aside whose deadline has past a year ago🤣
You should definitely do it. You don't need to spend a lot either. Get yourself a ESP32 or ESP8266 or an Arduino Uno - and some basic components and you'll be going onto more advanced things in no time. Always a great place to start as they're cheap and easy to learn basic principles! Good luck :)
Great video as always! The only thing that wasn't very explanatory to me is what and why was exactly calculated to realize the under voltage protection
The other day I connected a 3.3 volt voltage regulator to 12 volts. Switching the switching power supply on and off went well several times. But when switching, the power supply unit must have charged itself to over 14 volts, limit of the V regulator. The voltage regulator short-circuited and the circuit behind it suddenly had 7 volts. I heard the 4 volt tantalum capacitor explode. The IC behind it was specified up to 5.5 volts, but survived. From my box I then put a diode and a 78L12 in front of the new 3.3 volt voltage regulator. So the 3.3 V regulator doesn't see more than 10 to 12 volts, that's in the rules. The 78L12 will not be able to regulate well with a 12 volt input, but it will certainly withstand voltage peaks. I didn't have a 78L09 that would be the better choice. Another possibility would be to build a 3.3 volt regulator with an LM317. But I didn't have any space left.
I normally purchase from Jameco since they have reasonable pricing and wave shipping and handling for orders over a certain limit. I used Mouser a few years ago since they were the only supplier that had a specific value inductor that I needed for a MMIC circuit. Shipping UPS ground was at a flat rate of $5. Just now I checked and they charge $7.99 to ship an order via UPS ground, UPS 2nd day, or FedEx 2nd day. They have no minimum order requirement. Tbh, it isn't worth placing a small order. I'd order a lot of ten at 79 cents each or add other items to the order.
And then come the EU customs. 23-27% tax on all costs (parts + shipping), then customs and customs handling fees added on top, then you pay VAT on the customs handling fees as well. That's how you pay $70 for $2 worth of parts. And the paperwork, oh misery.
Why not use a diode bridge and ldo? It'll CONVERT to the correct voltage, AND correct any polarity to the circuit. The LDO can be chosen to avoid over current. Some have thermal shutdown too.
Those efuses are a different thing. The ones in this video are like fuses but better - more controllable, resettable... The Samsung ones are a bit more evil. They will blow if you modify the firmware and there is no way to reset them. A similar concept is used in laptop batteries, if the BMS circuit detects any problems it will blow a fuse and disable the circuit, making it unnecessarily hard to repair the battery.
Spectacularly good timing having just got to the point in a project where I'm thinking about protection circuits. I discovered that, having laboured long and hard on the project, it draws so little current that the power banks I've tried to used to power it simply switch off. We're back to batteries and the inevitable possibility of some klutz (likely me!) getting the power in wrong. As ever, great video. Thanks 😊
It's an absolute non-feature, they should at least make it possible to disable. I guess you could always add a parallel power resistor that burns off some extra current to make the ""smart"" power bank know you don't want it to shut down. Sounds incredibly stupid when thinking about it, intentionally wasting power of a battery... Good lord, modern electronics.
@@westelaudio943 yup, the extra resistor running in parallel would likely do the deed, but we're agreed that this is a complete waste of power. I would have thought that a function to switch this mode off on a power bnak wouldn't be too hard to engineer. A long press on the power on button, perhaps?
You videos are always fun and informative to watch. Just a quick note, absolutely nothing negative, but somehow you tend to add an "s" after a consonant at the end of some words, while speaking. Is it because German is your motherlanguage? Anyways, two thumbs up!
Probably pointed out already but so far the comments I have read did not say it. What I generally do to add a simple reverse voltage protection, is just using an bridge rectifier. There is a small drop in voltage but in the cases I have used it, it does not really mater. With this, more than a protection it allows to use whatever polarity you give to it. Did not know of these circuits either.
But then again my circuits look very different to yours. I use a lot of relays and premade modules, because I don't have the time or patience to solder or prototype stuff.
These Efuse IC's are very different to the current limiting automotive fuses. This chips are mainly interested for variable voltage power supplies such as batteries - and protect from undervoltage, overvoltage, over and under current and reverse polarity, rather than over current. they're mainly interested for areas where user error is involved and server grade equipment rather than a standard fuse.
I find it easy enough to use a simple diode for reverse voltage protection. A step further would be a bridge rectifier. Either would prevent current from flowing in reverse through the project whatever it might be.
That's a good solution for a fixed power circuit but if you're using batteries you're reducing your voltage headroom by whatever the diode reverse voltage is. Using a P-Channel mosfet gets around that issue since you can spec ones with really low Rds on. I did that for a battery powered high-precision frequency source last year.
"where's the fun in reading the datasheet?" 1 min later: "according to the datasheet..." I joke, you have great detailed videos. Thanks for explaining even the basics, this helped more than my undergrad degree ever did.
Clara, there are some of us who are book worms when it comes to Technical Manuals, Data Sheets, Schematics and Parts Lists. LOL I just can't sit down and read any novel or any book. I just don't have the attention spa....... Oh... sorry. LOL But give me a Technical Manual or such and I'm right into it. Go figure. 😉😁
Hi. I am late to the party but when a short is created on the circuit, does power resume immediately when the short is removed? Or is there some sort of reset necessary?
My expirence states that Arduinos/AVRs don't really need reverse current protection if fused. When connected backwards - those start to fry consuming more than 500mA tripping fuses before any real damage is done. Don't want to experiment though.
Bro please tell you how great of all electronics hobbiest and best of electronics is Great Scott And how you learned all the basic electronics and how to understand the circuit diagrams easily to make a project by understanding the circuit diagrams because of difficulty to understand the circuit diagrams
Do you warn JLCPCB of the upcoming demand, before you create these videos? I see that JLCPCB does have one model in-stock for SMT assembly (with limited supply)--but I wonder how long that will last, now that you've educated everyone!
I have always meant to ask you what you do with all the drawings you make in these videos. Do you keep them all or toss them or what? I really want to know so please tell me. Love your video BTW. I don't really do much electronics work, but I still love your videos!!
can you make a device that control multiple batteries (having seperate BMS, different capacity, different age). the device can have multiple terminals to connect multiple battery banks and able to control charge/discharge without hurting the older/smaller battery. I think this could have potential application for solar battery bank that we can combine any batteries with different types, ages and capacity.
