The Resistor That Doesn't Resist
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- čas přidán 23. 07. 2024
- Join Shane Oberloier from Michigan Tech as we delve into the intriguing world of 0 ohm resistors in this educational video. Often perceived as a component that does 'nothing', 0 ohm resistors hold a unique place in electronics, and their purpose is far from futile.
Key Highlights:
🛠️ Ease of Circuit Board Routing: Discover how 0 ohm resistors simplify the design process, particularly in single-layer circuit boards, by acting as efficient conduits.
🔗 Functioning as Jumpers: Learn about their role in isolating circuits, serving as reliable and convenient jumpers in complex electronic designs.
🔄 Stand-ins for Redundant Resistors: Understand how these components can replace resistors that are no longer necessary in a circuit, maintaining design flexibility.
Bookmarks:
0:00 Introduction
1:15 Use 1 - Routing
2:34 Use 2 - Jumpers
4:57 Use 3 - Stand In
In-Depth Exploration:
Shane Oberloier, an electrical engineering professor at Michigan Tech, takes you through a comprehensive journey explaining the practical applications and the underlying reasons why these seemingly simple components are integral to modern electronics design.
Stay Engaged:
👍 Like this video if you find it informative.
💬 Comment below with your thoughts or any questions you might have.
🔔 Subscribe and hit the bell icon for more insightful content on electronics and engineering.
Learn More:
www.mtu.edu/ece/
www.oberloier.com
Hashtags:
#ElectricalEngineering #CircuitDesign #ZeroOhmResistors #MichiganTech #ElectronicsEducation - Věda a technologie
PRO TIP -- PHYSICISTS HATE THIS TRICK!
solder a ton of them together in place of wires to make a circuit with no resistance. It's the room temperature super-conductor they don't want you to know about 😎
Solder has resistance! BUSTED
Twist them together@@violinviolator5841
@@violinviolator5841 That's what they want you to believe...
@@violinviolator5841on proper solder, the solder would never be an actual conductor.
@@violinviolator5841Melt these magic resistors down and use them as solder
I didn’t hear you say the reason that zero Ohm resistors are used instead of simple wires. I believe the answer is automatic pick and place machines. A zero ohm resistor, whether through hole or SMD, is the same form factor as the other common components and thus will work in automated machines that aren’t configured to insert wire jumpers.
I was wondering, too, why not just conventional jumpers. Several good reasons below; but, yours is probably the most salient, at least for production purposes. In the end, it is just a matter of cost and/or convenience as to which to employ, it turns out. Just one more practicality choice. But, like you, I presume, I *do* wish that the video had addressed such basic consideration of deciding upon the most apropos per the particular situation.
Zero ohm resistors also allow better isolated bridges for power applications than simple jumper wires, where conformal coating/enameling wouldn't be enough, but insulated wire would be overkill and require special configuration in your automated process to take it.
These answers combined with a video are a great example of the difference between the theory of academia (where Dr. Shane is coming from), and the practice of industry. Shane uses them for a bunch of experimental reasons - jumpers, stand-ins, because that's what he has to hand. Industry uses them because it means they don't have to retool a different machine.
It's like when people complain about, say, a mail-order company using a 2-litre box to ship something that's maybe a couple of half a litre in volume, but the fact of the matter is that it's more efficient for a shipping company to run only a few standard sizes of box instead of having to track dozens of specific sizes and figure out how to send each.
You are correct. That is the only reason they exist. Could have been explained in a minute.
@@Peter_Riis_DK True, but who makes 1 minute CZcams videos on topics other than the stupid things in the shorts videos. It should would be nice if people could make videos only as long as they need to be rather than pad them with filler for 15 minutes.
I worked in electronics industry in the 1980s. The primary use of zero ohm resistors with leads back then was with single sided circuit boards. They are shaped like a resistor because they would arrive into the factory on what we called “tape and reel” - a thousand resistors evenly spaced on tape that holds the tip of the leads, then rolled up on a reel. The tape and reel format was how through hole component insertion machines expected components to be. The resistor would be grasped by the machine, the leads clipped near the tape, the leads would be bent to the spacing that is used on the PCB layout, and inserted through the holes onto the board.
We used them on double sided PCBs too, when that was needed to cross an area where traces ran on both sides of the board.
Exactly. They were used by "pick-n-place" machines to cross existing traces.
1 Routine
So it fitted in with the way things were otherwise done in the factory.
It's called a jumper wire, and they were in use without a resistor body.
@@rootbeer666 - they were in use without a resistor body, but some automated machines needed the body as part of how they operated. That was back in the day when surface mount was in very limited use, so PCB layouts would have little problem with allocating space for a resistor body - because all components were at least that size.
So primarily in place of a jumper wire when a pick and place is used?
They're used as fuses from time to time, and they're also useful for pick-and-place machines in lieu of bridge wires as other comments have mentioned.
I figured that was a possible use, but didn't know if there fail point and mode was useful for that
ive seen them used this way in some apple laptops
Same here. I've heard them called fuses much more than his 3.
I figured it was just a Borg resistor: “Resistance is futile.”
feudal or few-tile?
They are good on machine pick-and-place assembly as the set up is the same as a standard resistor so no need for a special tool to insert a wire link.
Also they are used in pcb re-use so a board designed for one purpose can be used later in a depopulated configuration which meets the requirements of a different application without increased stock
you looked it up on wikipedia too? 😂 Lucky us watching a video with 3 incorrect reasons first...
Thank you! I'm a software guy and barely competent with a soldering iron, but I recently bought a build-it-yourself frequency generator which included a zero ohm resistor. I wondered why it was there, but after watching your video, I looked at it, and -- sure enough -- it was used as a bridge. Thank you! This is fun!
hey, can you share the product page for the generator? thank you!
Some use a low or 0 ohm resistor as a intentional weak spot or fuse in order to protect more complex and/or expensive parts of the devise in case of a malfunction so a repair will be cheaper and easier to do. This is often used with fuses in the same Circuit to avoid cascade failures.
Our electronics teacher at school taught us to use these as link wires on pcb’s. He had a lot of experience doing aeronautical electronics on planes and was hands down the best teacher I ever had. Didn’t really have a huge interest in electronics but took the course because he was so good
Another reason for a zero Ohms: Sometimes in development, you want to measure the current being taken by part of the circuit. To do this you may take the zero ohms out and put the meter there or just make it something like a 1 Ohm resistor. When it goes to production, you don't want to do a new layout.
BTW: If you position two resistors side by side at just the right spacing, you can put resistors in as you normally would or you can put them in a 90 degrees. This can make one go from pin 1 of R1 to pin 1 of R2 instead of connecting to pin 2 of R1. This can be very handy for providing alternative wiring on a circuit such as selecting which pins of the micro go to what.
Actually sounds like a genius solution to that inconvenience. Never though of that.
As someone that used to do component repair, I'll mention that these are SUPER useful for testing for the same reason. You can isolate whole sections of board with a few desolders and test them very quickly. This enables much faster repair than when they aren't there where you may need to know a ton more about the particular circuit you're working on before doing any meaningful testing.
If the current in that connection matters during development, odds are it's also going to matter during production and will need to be measured during testing. And to test each of 50 000 circuit boards by leaving a connection open to introduce an ampmeter to then make the connection later is a pain in the rear end.
There is a much more convenient way to measure current. Do it indirectly. Add a low value resistor, measure the voltage drop across it and use Ohm's law calculate the current. Sure, the manufacturing tolerances of the resistor make the measurement less precise, but something like an E48 ought to be sufficently accurate for most contexts. Yes those are more expensive than 0 ohm resistors, but saving the money you'd have to spend in order to do additional soldering after the testing was done - and then do the re-testing that is needed after the soldering job, easily outweighs the more expensive resistor.
@@MrAranton In real life, things often are needed in development or in trouble shooting that are not needed in day to day production. For production testing, the fact you don't have excess current drain can be checked for the entire board. Finding the culprit is where you may want to break into sections.
@@kensmith5694 I guess there are different approaches to that.
My employer operates on the philosophy that testing done in production should be more than just proof that the unit is working within specification. It should also provide information for trouble shooting. But then we mostly use automated testing rigs than can perform hundreds of measurements in a matter of minutes or even seconds.
So if a unit doesn't pass, the test report usually has all the information you need to figure out what's wrong and to decide whether or not it's worth fixing. If - thanks to extensive test reports - it just takes a couple of minutes to identify and replace a defective component a unit with a sales price of 20€ is worth fixing. But if a skilled technician spend the better part of an hour just figure out what's wrong? Not so much. The way the company I work handles in-production-testing minimizes discard and I don't like wastefulness. But I get that other companies have a different approach and that not all discard can be avoided.
But I digress: At my employer development is done with this philophy of testing in mind. Testing anything that's close to what the final product is supposed to be in ways that can't be replicated by an automated rig just feels - off and clumsy. Maybe I'd see that differently if I worked at a company with a different philophy.
The main reason to use in place of a wire link is for pick and place machines. They can handle resistors - a bit of wire is new tooling. For a hobbyist, a bit of wire is fine.
Thanks for confirming that. Seems logical. There was one in a reference design for an EPS32 and that seemed really weird. Any explanation why it would be there? Somebody said it’s a fuse, but that doesn’t seem very logical.
@@OMNI_INFINITYzero ohms still have *some* resistance just like everything else, so they'll eventually heat up and melt just like a regular fuse, just with the lovely smell of magic smoke. However the current it'll pop at is a rough estimation based on the resistor's size. It's not exactly the most preferable option, but it's good enough to prevent a catastrophic short from being a fire when used appropriately.
Could also be something else such as a design limit (single sided board or weird routing limitations, which aren't uncommon on boards going for minimal size) or for selecting an option of some sort. Couldn't tell you which for sure without seeing the schematic.
@@OMNI_INFINITY Iv'e been in Professional Electronic Repair for over 42 years, yes they are at times used as fuses. It's not common but I have seen them specifically used that way.
In a professional field where Runs must have a jumper, a bare wire is never used because over time it can work its way through the run masking and short out, the exception to the wire jumper is if it is insulated. So the best alternative is to use a known size and package that machines readily are designed to grasp and place, so the zero resistor package is used for ease. Seen it over and over over the last 42 years of my profession in professional electronic repair. As a hobbyist at home and a few times at work, do use an insulated wire because I don't have a pic and place machine. If we or I had one for production I would use the zero ohm in it's place. The exception at work is even if we don't have the machine sometime we still have to use one to meet spec by the part number in the manual.
Thank you. I have worked on electronics for nearly 70 years and it is only recently that I heard of zero ohm resistors.
Thanks. Now I know how they are used.
I use zero ohm resistors for "select by test" components in machines that need to be calibrated. Sometimes you need to finely change the resistance of a circuit, but resistors only come in certain set values. Like you can get a 100k and a 110k resistor, but what if you need a 105k resistor? In that case you can have two resistors in series, a 100k (coarse) and a 5k (fine). But for another copy of the same machine you might need exactly a 110k resistor in that path. Then you can't just leave the pad open, so you'd use a 110k resistor (coarse) and a 0Ω resistor (fine) to calibrate that one.
0 ohm does not have any tolerance series.
Apart of being used as a bridge resistor, I've seen 0 ohm resistors being used as inexpensive fuses. They behave linearly and can stand around 12 amps per watt, so a 0.25 watt unit can stand 3 amps, 0.5 watt 6 amps, 1.5 watt 18 amps and so.
I'd like to point out that a wire link has always been the go- to for hobbyists
And often in production with previous through-hole technology
Zero ohm resistors are far more common on surface mount boards that are likely assembled using pick n place technology
This is the first time I've seen a wire ended zero ohm resistor
I know someone who many years ago was designing something for the military. They were told that they were not allowed to use jumpers of any type on the PCB. They solved the problem when they had it by using a 0.1 Ohm through hole resistor in a few places. To make an excuse for the existence of a resistor in the VCC line of a chip, they add a line to the test procedure where the voltage from on the 0.1 Ohms had to be measured and noted that is was less than 0.1V.
@@kensmith5694 I designed
Yes ! this is typical of the nonsense that the military procurement get up to ! ... in the UK some years ago the standard was HYPER neat wiring with lacing cord to keep the wires neat ... this took AGES to do ( @ MUCH cost ? ) , then they would take your wired missile and blow it up ... a simple wire bundle in a trunking ( much as electricians use ) would be 100's of times cheaper ( and , still work ! ) .... DAVE™🛑 @@kensmith5694
@@jim9930 Yes, these are often called a "gimmick"
A wire is fully conductive, while the zero ohm resistor element is not. This makes the chance of a short-circuit much smaller if the element gets bent out of place.
Last year I was learning a bit of electronics diy. I was disassembling broken stuff and found plenty of these and was kind of surprised they existed.
One of the things I had read when I was looking up why they exist was that it can be easier for pick and place machines to pick up something that's the same size as all the other resistors.
You brightened my day when you said Michigan Tech. I earned my BSEE there in the days of the old Hotchkiss Hall, 68-72. I've seen and used the 0 ohm resistor many times.
Used in 88 and on GM electronic speedometers to calibrate circuits for different tyre sizes and final drive ratios.
Factory had a device that bridged the 0 ohm resisters, then put a high voltage through them to blow them, in a combination to set the frequency ratio of the speedometer in hardware instead of flipping dip switches, as in VDO speedometers, or shifting jumpers.
All calibration positions had the 0 ohm resisters and they were blown with the special device to match the desired.frequency from the Hall effect sensor in the gearbox output stage.
You can replace all of the resisters with a dip switch on a fly lead to recalibrate the speedo or just mess with peoples tiny little minds by making an imperial speedo indicate metric and back.
A trap is if someone who doesn’t understand the circuit thinks it’s all wrong and replaces the 0 ohm resisters with another value or replaces the blown ones they either kill the pulse counter or mess the calibration up royally.
Fun things these mystery parts.
That's interesting! Seems crazy how that had been deemed the best solution to make a calibration.
Sometimes it used to set address of an i2c slave (i2c sensor). Most of the hobbyists just bridge them with solder, but in assembly line it's done with zero ohm resistor.
My dad was working on his electronics degree when I was a kid and explained these to me because he was fascinated and amazed. And he explained how it was beneficial for the same reasons and how he had seen it gone wrong. I am amazed in those rare moments when it comes up how few people know they exist.
This was amazing! An answer to a question that just recently started asking myself. Thanks a bunch!
2 and 3 I've used plenty of times, but your first example is actually something I've never considered. Pretty slick.
Great, simple, approachable explanation. Thanks!
nice! i haven't used these before, i've just used my collection of component legs as jumpers. this would definitely be a great alternative to this that would avoid shorting.
to elaborate on #3
we often use them in series and or parallel with our first best guess on analog circuits that are compensating for parasitic quantities not precisely known in the design (eg. in analog feedback loop stability, gain compensation, emc filters, and snubbers, etc)
You just couldn't resist putting this video up.
this is how youtube videos were meant to be
i love it
thank u for the information
The other use is for diagnostic isolation. If you arent sure what part of the board has a fault, this allows you to break thr problem up to be able to concentrate on a specific part.
ever heard of a jumper wire?. an actual wire?
ever heard of a jumper wire?. an actual wire?
@@kofi8259 why would you use a wire on an smd board? If I purchased a motherboard or a macbook and it had a wire where the zero ohm resistors should be, it would be going back to the store.
Great video! You have a real talent for explaining things. Subscribed
Just last week I used a zero ohm resistor for the first time- on an ESP32 board to configure whether it should utilize the on-board antenna or an external antenna. There were three pads in a v shape, and you connected either the left or right to the center with the zero ohm resistor (you could also use a wire or just solder if you had to) to enable that antenna.
I also remember seeing these on computers that had "turbo mode" switched always on (didn't have the turbo mode button).
Funny, I didn’t realize this was from my Alma mater, and I actually know you (at least in passing). Thanks for the video.
I was accepted to Michigan tech but it was too cold for me. Love this educational content!
Another use for 0ohm resistors is cheap and compact Fuses. Those SMD or even axial resistor have a tolerance of about 0.25A so anything higher than that will blow the resistor.
I'm sold on the surface mount zero ohm resistors as jumpers across tracks, that is certainly automated production friendly, but the through hole version still just has the feel of a DVD rewinder when wire works just as well.
Very common place where I see those is connecting ground planes together. You might want to control how the ground currents flow, and this can be tricky to simulate and calculate before testing on final board. Also you might need to disconnect the logic ground from chassis ground, or replace the 0 ohm link with capacitor for EMI reasons.
I have even seen 0 ohm through hole resistors used as interconnect between stacked boards serving spacers at the same time.
A very complicated explanation for a very simple "problem".
The _NOP_ of circuitry.
Good one as you could later add resistance if needed the space is already there. also Resistance is futile
The Borg: Resistance is futile!
Dr. Shane Oberloier: Hold my beer...
The first time i saw a zero ohm resistor was last year and after asking our teacher if it was used kinda like a jumper getting confirmation that it was i love using zero ohms when i need to connect short places in a single layer board
I like using zero ohm resistors as superconducting magnets. But you have to make sure they didn't cheap out and give you a 0.05 ohm resistor or something like that.
Black Black Green Gold
0.0 MΩ, ± 5%
sometimes they screw up and give you a -0.05 ohm resistor, then you've won the jackpot
@@1224chrisng That's something to think about: V=IR makes either V or I negative, thus P=IV is negative. Luckily resistors with such small values tend to have a high wattage rating, we wouldn't want it to burn out while trickle-charging your car battery 😛
@@1224chrisng 5% of 0 is still 0. But in fact 0 ohm resistors have a conductor resistance which is higher than 0.
As to jumpers I have also seen them used to configure things like network addresses. The resisters are put in place to give a default address. Then the field tech can clip the resistors off with just a set of cutters to configure the address to the system the device is being installed in.
Zero ohm resistors could also be used as a substitute component... imagine a bare-board PCB that is shared between many sub-models within a product range. Depending on the features available on a particular model, different resistors will be populated by the pick-and-place machine at a particular ref-des locator, while avoiding the need (and added cost) for a PBC with a different part-number.
Zero-ohm resistors, could also be used for isolating different parts of the circuit, for testing, or for diagnostic/fault-finding.
ESD sensitive devices could also be protected by zero-ohm resistors while a sub-assembly circuit board is waiting for final assembly, or during transport to a different factory for integration etc.
Also be aware that some components may appear as through-hole resistors, but are in fact fusible resistors, while others can be inductors. Test with an LCR meter, with component out-of-circuit to be sure.
I had negative ohm resistors to show off, but were conserved contraband at the stargate exit portal.
This man has done it. He found a room temperature superconductor.
I've seen them in a gauge cluster to fine tune the speed, which always had a bit of deviation in analog speedometers.
The previous model used a potentiometer, but they changed for jumpers with resistors which could be enabled/disabled to adjust the needle position.
There also was one in my car ecu, which served as a jumper and had to be moved if you wanted to read an external rom instead of the factory one.
Tuners used it to store new maps and transform the stock ecu into a reprogrammable one, before they all used flash rom instead which could be reprogrammed without hardware modifications.
WOW!! This video just blew my mind! Never thought about using a zero ohm resister to make routing better!
This is going to revolutionize my PCB creation!
We used this in spots where we were uncomfortable with our assumptions, and allowed for the ability to add resistance to some leads where we should not need them. In the second revision we knew if they were needed or not. Also can allow a production time signal switching.
Cool. 47 years as an Industrial electronic electrician, and I never saw one before - I think. Was the square looking 0 on top of the SMT's an identifier. Retired now five years out, but I can only imagine series and parallel circuit math, whereby I need no math to figure it out🤣🤣 How many watt are they? Do they ever short out? This could make a fun electronics cartoon series
In working with many systems in the Navy, we called resistors with 0 to 10 ohms, sacrificial components. This is because they were basically like fuses, anything high went through them, they would pop quick and were easily replaced. Also, the large carbon resistors were absolutely designed for that reason.
While the resistor may have no resistance, do they come in wattage? As I use different size buss wire for jumpers for the expected current. Are there different lead guages. It would clean up some of my work for sure.
I've mostly come across them as quick blow fuses. LED light bulbs often have a low (but above zero) ohm resistor connected to one of the pins to both current limit, but also act as a quick blow fuse. They seem to be more precise, as you can calculate the exact current for the resistance that will produce a certain temperature. In these bulbs, they will usually be in a heat shrink tube to contain them in the case of any catastrophic failure (although I've only seen them fail invisibly). They're pretty good at failing quickly before any damage to the circuitry, protecting even transistors in CFL bulbs in the case of power spikes
You mean resistors smaller than 20Ω in switching power supplies and LED power supplies.
In the event of a short circuit, the maximum power of 0.25W is exceeded and the resistor burns out.
At 20Ω and 100V it is already 500W
But it makes no sense to use 0Ω resistors
@@jensschroder8214 "At 20Ω and 100V it is already 500W"
Some more research says that you can indeed use a 0-ohm resistor as a fuse, but you need to be careful which version you use,. There are those that are just a wire with a resistor-package glued onto it, and there are actual resistors with a 50mOhm value so they will fail just like a normal resistor when you exceed their rated power... becuase they are normal resistors, just with a very very low resistance.
I've encountered these before. For some reason, they are not uncommon in DIY Eurorack synthesizer modules. However, I've also used leftover clipped leads for the same purpose. I'm not sure why the ceramic type is used.
I've seen them used as protection devices. In some situations a fuse would not blow fast enough but a 0 ohm resistor would. Antenna inputs to radio receivers often use one in series to protect componets further down the line.
They also match impedance more closely than PCB traces when you have precise requirements like a differential amplifier op amp configuration; by using a 0.01ohm resistor and a 0 ohm one, both have the same resistance between the leads and PCB and length of the resistor itself (compared to a PCB trace) which cancels out perfectly.
My main uses are as jumpers/configuration devices (especially in open source hardware design) or as stand-in. If you have a possible required requirement for a ferrite bead or inductor, you need to bridge it with something, as long as you don’t know. This is for electro magnetic compliance purposes. In consumer electronics with high volumes, it makes sense to remove the not required components. Industrial electronics very often, is not produced in high volumes, so the 0Ω resistors stay, since the money saved by removing them, does not pay the required board redesign.
I've only ever used them to do routing on PCB. For jumpres I'm not a huge fan since desoldering one might need soldering tweezers or applay large amount of flux, which migh need to be washed if it is active. Just having bridge made with solder is fine. For tweaking sure, though on dev boards where I'm not sure I will just plop a trimmer.
Are there cases where the same circuit board could be used for multiple applications that just require different soldered components? Have 1 PCB for 2 different parts
Yes, lots of stuff like SATA adapters have the same board for 2 or 4 ports. Or 2- and 4-channel oscilloscope using the same board
🎃 Thank you, you just gave me my next Halloween costume!
A wireless doorbell I've had actually has three or four 0 ohm resistors standing tall and accessible from a compartment, so that you can make one time adjustments by cutting them to shift the frequency the buzzer emitted and receiver paid attention for, so that you and your neighbour could both have buzzers, and only the correct receiver would go off.
Well, it's basically a bridge or just a wire? And it's used for automatic circuit assembly machine then?
One of the best uses I've seen was an SMD 0403 placed without electrical connection, next to a right angle SMD pinheader, to prevent accidental unhooking of the Dupont connector.
That zero ohm resistors is the only ways to disrupt my friend's Arduino projects without him ever knowing that i changed the resistor
pretty cool way of going above some traces an connecting some signals that you could not connect without adding an extra pcb layer. Comes to think I sould have used them in place of capacitors for one of my projects that has 3 uses depending how you populate the PCB, one use case requires bridging the capacitor holes
I like zero ohm resistors for breadboard use, it's just so much easier and neater than having to grab a wire jumper
this is very clever
Yep, I do as well. Much neater.
0 ohm resistor? No resistance? So, we DO already have room temperature superconductors! 😂
In fact, zero ohm resistors have a negligible conductor resistance.
Just found you, nice video. Maybe because I look for MTU related topics on a regular basis.
In a related example, I disassembled a night light and found two 10k resistors in series. I was puzzled when nothing connected to the mid-point between the two resistors. It wasn't needed for power or voltage rating, and didn't simplify the bill-of-materials.
Then I realised that BOTH resistors had tracks running under them. They split one resistor into two so they could use a dirt-cheap one-sided PCB.
More recently I've used two zero ohm links as bridges on a PCB that didn't need to be cheap, but where for safety reasons all tracking except ground had to be on one side.
This is interesting and perplexing to me because I did an AAS and BSCT and never did a zero ohm resister come up!
I use a lot of these 0ohm resistor as shunt on datasheet describes this use case, as the voltage drop is more acurate than a simple wire on these components you can get a really good resolution with 32 bit adc
Hi
I havê never seen a THT 0 ohm resistor. Thanks for showing.
I have at work several ST testing boards that features them also. They are used exactly as shown on the texas board. You desolder or solder them to enable parts of the board.
I have seen low ohm resistors to be used as shunt resistors for the purpose of measuring current. Actually quite big selections with miliohms range and several watts of power rating. Not sure if that would apply for 0 ohm resistors...
Onve again thanks for the video.
The datasheets for 0Ω resistors list their maximum resistance and amperage ratings. For a random 0603 part: max 1A (2A for
Hi ... excellent video, a query what is a current sense resistor ? Is it same as zero resistor ?
A current-sense resistor, is usually a higher-wattage resistor with a tight tolerance. They are used to calculate the current flowing in a track by measuring the voltage drop across the resistor. The voltage-drop is sensed by the connected MCU. As a voltage needs to be dropped across the current-sense resistor, it will have a low resistance value, but can not be zero ohms.
If the zero ohm resistor is made of same stuff as regular resistor you could use it as a oc fuse. So off to much amps go through it just pops apart ?
Hey shane, can look at an ESP32 board design I made and tell Me what needs to be changed to make it function nicely? It’s on the jlc board sharing pages.
I've never come across a through-hole 0R but plenty of SMDs - I kind of assumed they were mostly for routing or as jumpers but nice to know my hunch was correct 😁
I have a load of these THT and SMD, the through hole as 1/4w, 1/2w and 2w, the 2w I use as jumpers in power supply circuits usually 2 in parallel to reduce resistance,. A THT ferrite is also useful as a jumper where noise is an issue like in switch mode circuits.
Interesting video
Didnt know 0 ohm resistors were a thing
That other 0 ohm on the board you made is even more of an example of routing of traces.
I often use them in replacement of an inductor I do presently have.
Sometimes in the THD aera it was mechanically easier to place a resistor package instead of a wire bridge
I'm reminded of a piece of "magic code" I found in a lua script circa 2008. It was commented out, old version of what was functional earlier in the script, but it had a warning not to delete or it would break the NPC it controlled. Since that's silly, I deleted the commented lines.
The NPC broke. (I'm sure it was a silly overlooked error, but it's still funny)
Zero Ohm Resistor: exists
Engineers: STOP RESISTING!!
yea I was wondering about the same thing when I oftentimes saw 0 ohm smd resistors, which was like, why even, but it all made sense then.
I actually learned something interesting, always thought they performed a filtering function.
It's funny, you've done electronics up through university (grad school, post grad, etc) and i did it during secondary (high) school and I'm guessing we're both millennials but at either end (my secondary/high school finished in 97) and the difference in the projects and technology is stark.
The most advanced _anything_ we had was a 555 timer.
Or equivalent of a Pi or that little mcu board everybody uses was a full size microcomputer with a gpio connector (bbc micro 32k)
And we're the _same cohort._
Crazy how it changed in just the 90s.
Arduino. That's the little mcu board, i always forget.
It was a real "Head Slap" moment when it dawned on me. Everyone that had asked me why they existed got the same "Why didn't I think of that?" look on their face when I went back and told them.
At home I still have a whole old amplifier set that use wire instead of 0-ohm resistor for routing. The board is one-layer two-sided, with all through-hole components and a lot of "short bridge" using wire (I call them bridge because I see they bridge over multiple cross running traces).
Current Measurement: They can be used for measuring current without affecting the circuit's performance, by replacing them later with a shunt resistor for current sensing.
Soldering Practice: Beginners in electronics use them for practicing soldering, as they are inexpensive and mimic real components.
Manufacturing Convenience: In automated PCB assembly, 0 ohm resistors can be placed by the same machines that place other components, streamlining the manufacturing process.
Component Protection: They can be used as a safeguard, easily removed to isolate parts of a circuit during testing or troubleshooting.
Facilitating Manual Assembly: They help in manual assembly of PCBs by clearly marking where connections should be made, reducing the likelihood of errors.
*So main purpose in the industry is primarily in place of a jumper wire when a pick and place is used?*
On that first circuit board, it looks like the solder gets extremely close to the track the 0 ohm resistor is crossing. Wouldn't a wire be a better option in that use case so you can get better separation? That could very easily end up shorting.
4. slow acting fuse. A lot of them are used for that purpose, it is the first component to burn if things go out of order.
What is the tolerance on the zero-ohm resistor? ;)
I have seen them listed as 5% and as 1%. I think the folks doing it know its nonsense but the form describing resistors has an entry for it that can't be left blank.
Many also have a power rating.
@@kensmith5694 So do they bin them too? lol. I'm trying to market my infinite ohm resistor but seems a lot of opposition to it....JK
@@lidarman2 I tried to market 0.5pF capacitors as halfacitors but it didn't work.
@@kensmith5694 Hilarious. Well I can tell you that I commonly create infinite ohm resistors at work and they have a tolerance of +/- 0% until you increase the voltage to a few kilovolts and then they become near zero ohm resistors.
I've not seen it exactly with 0 ohm, but one use case might be to mass produce small boards that can be changed to fit specific requirements after manufacture.
For example, the TP4056 charge controller has a "programming" resistor that can be replaced to tune the board to match ideal charge current to different battery capacities.
The three reasons stated are likely not the reasons that these parts exist. Years ago before surface mount components became the norm, circuit board manufacturing used specialized equipment for automatic component insertion, and this equipment was designed to use parts that are shaped like a resistor and could be physically gripped the same way. If a jumper or wire is needed on the board, a zero ohm resistor is used because the equipment can grasp it, and it can't work with plain wire.
All true. In my shop we hand stuffed boards on a slide line and I still used them. Easier to grab and insert by hand as well compared to a bare wire.
Two more uses(which is usually seen in mature commercial products):
1. Used to connect the signal ground to the power ground. It's 0 Ω, but it still has a bit of impedance, which can help to reduce the crosstalk.
2. Used as a simple fuse. Of course a real fuse with a rated current is better, but sometimes we can get away with just using a 0Ω(or a small resistor like 1Ω) of a desired size.
By the way if we need a jumper, we usually use a copper jumper wire instead. It's much less likely to fail, especially when there's constantly some current going through it.
Can someone tell me of any device that helps drain negative ground energy off of any conductive surface?
I've seen the SMD ones conveniently placed on the path of series LEDs inside a a spotlight, they were just bridging over some traces, while being in the exact place I needed to cut the traces to do my modifications to the board - so I just took them off and it was ready to do my thing. Very convenient.
But the proper 0ohm resistor shown...
I remember seeing wires used from factory on some CRT TV boards to jump over traces - and there were lots of them, but they were machine placed. Which begs the question... just why call the thing resistor and have the thing look exactly like a resistor if it is nothing but a wire? Why don't we just call it "jumper wire" or smth...
This take me back to 2004
When i use 0 ohm for the first time in denon amp
This past summer, I diagnosed a Mitsubishi split A/C control board that had what appeared to be a diode, white stripe at one end and black body. But had zero resistance in either direction, the problem turned out to be a transformer. So I assume it was a zero resistor , but why look like a diode?
It is very useful for anyone that has to troubleshoot your boards
Imagine having 100 bypass capacitors all in parallel on your board. You then find the board doesn't work because 1 of those 100 caps were shorted, bad, etc. If you group the caps in groups of 10, finding that 1 part becomes much easier by removing a few resisters and isolating the groups.
i always had one question about those 0 ohm resistors
how much does 0ohm resistor work as a fuse
because it has both package size of a certain power resistor, but ohms law would make it infinite so since there is no infinitly low resistance it must have some value too other than 0 and some fusing characteristics
I guess it’s use as a fuse would be determined by its power rating. By using some basic formulas I recon you can find a maximum current limit at the voltage of your choice. Since these are probably quarter watt resistors, maybe you can push something like 50 mA at 5 volts before they blow? (All of this is just my opinion btw)
We use 0Ω resistors in the avionics industry primarily as fuses. If you have components that can short when they fail, you don't want that current rampaging around and destroying or weakening other components/ circuits as a result of the initial failure, leading to a plane crash. We use 0Ω resistors as the 'canary in a coal mine' because they will open immediately, creating a metaphorical 'fire break', which we call a 'boundary zone'.
One of the many reasons why avionics are so expensive.