How does one profit from a novel circuit idea? - Page 1
Forum section: electronics / general

author: flowib
author_rank: Contributor
timestamp: February 17, 2021, 08:36:02 am
content: I have an idea i have never seen used before, and the first half a dozen pages of google patents turns up zip.I'm being vague here on purpose.Its an idea pertaining to operational amplifier, i figured high voltage power op amps where sub optimal and the stuff APEX makes is nice but expensive, and the fact that it comes in proprietary packages doesn't help. The idea in question is completely bonkers in that it uses Photonics for feedback instead of physical connections. And thus has enormous growth potential both in speed and in output swing.My idea was to use two external N-channel devices to get away from the drawbacks of P channel devices as well.I have so far contacted a couple of companies and have not gotten a single reply in days.What to do?

author: brabus
author_rank: Frequent Contributor
timestamp: February 17, 2021, 09:22:20 am
content: Patents are so 1800's.If you really believe your idea works, don't lose time: start developing it and sell. If someone copies your product, well it means the idea is damn good. But at the end of the day, only sales matter.If you are really damn good, you can sell the idea and the company altoghether to a big competitor; someone else will then rule out the patent situation.To be honest I don't see anything really worth patenting here, we are talking about a complete system and not just a single key concept you aim to protect.

author: Brumby
author_rank: Unknown
timestamp: February 17, 2021, 10:34:12 am
content: I wouldn't make any overarching statements about patents just yet.The ONE thing you HAVE to do if patents are on your radar is toNOT DISCUSSdetails openly. Even in closed door conversations, a "Commercial in Confidence" state of secrecy is paramount. If ANY significant detail becomes common knowledge before a patent application is lodged, your efforts will be in vain.That said, publishing details will prevent anyone else from lodging a patent - and getting to market first is not a bad recommendation.As for your idea - have you done a search of patents to see if someone has already traveled that road? Also, a few Google searches with a variety of search terms that cover the component technologies through to end use applications might also be worth the effort.Otherwise, just sit back and wait for it to appear from someone who's been working on it for years already.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 17, 2021, 10:51:45 am
content: So, some kind of optoisolator driven, or feedback, amp?Rest assured they've tried everything already -- one of the more peculiar examples that comes to mind was an HP electrometer, I think: they used varactor diodes as a parametric sense element, excited by RF, coupled by capacitors, so the DC leakage is extremely low. When the diodes are biased by a small applied (DC) voltage, the capacitance changes, sensed by a bridge circuit or whatever. The AC balance (or even harmonic distortion, I forget) is amplified and detected, as you would with any chop amp -- giving extremely high loop gains as well as extremely low leakage. This would've been early 60s I think, before JFETs arrived, or at least were very good?Anything you can transmit and amplify, has been used for amplification or control. Modern laser apparatus I suppose is an excellent example, some things working down to quantum levels of energy, or particle counts.It sounds like you'd be interested in analog isolation techniques?There are two major problems with a traditional LED + photodiode or phototransistor pair:1. The CTR is unreliable, over ranges of manufacture (device parameters, alignment, packaging), aging (LEDs lose some efficiency with use), and the usual current and temperature (giving nonlinear, temp- and history-dependent responses). As lone or feed-forward devices, they're terrible. As feedback devices, they can be acceptable.A typical use case is feedback from a secondary-side error amplifier, to a primary side PWM modulator: the isolator gain and offset is corrected by the loop.Another case is the IL300 and relatives, where the emitter gain isn't well known (see above), nor the ratio between two receivers (due to manufacturing variation), but that ratio is stable enough to be useful. The emitter's output is servoed to get a desired current in one receiver, and the other receiver will deliver a proportional current. These require calibration to use accurately, but are stable otherwise.2. Bandwidth. Optos are slow. The photodiode/transistor junction is large (high capacitance), and in the case of the transistor, has slow recombination too. The capacitance can be reduced somewhat by reverse-biasing it (diode capacitance varies with voltage, being highest at zero bias), and indeed such circuits are available, 6N136 for instance. Still better performance can be had with a smaller photodiode, integrated amplifier (probably some transresistance amp thing -- this forces the AC voltage on the diode to be as small as possible, minimizing the effect of capacitance), stronger drive, maybe some kind of lens in the optical path... LEDs themselves roll off in the low 10s MHz, and to go much higher you need lasers.So then we get into fiber optics: lasers, photodiodes, extremely high radiance; RF circuits and controlled impedances, etc. Gain is all over the place, the optical path might vary 20dB due to alignment, cable length and so on. Don't have to worry about that so much in a short path isolator of course, though there are applications where this is important -- optically triggered gate drive circuits for HVDC power inverters, for example.Anyway, all the gain and offset stuff can be solved with a modulation scheme. Typical cases are AM with AGC, FM with ALC, or various more complex RF modulations. It's still not easy to get raw baseband analog through these: AGC needs a known baseline signal level, so the signal needs to be momentarily keyed to 0/100% to set that level (analog TV did it this way!), or AC coupled so the average is consistent, etc. FM is a bit better, but your receiver's frequency reference isn't going to be perfectly matched; it might be nice to track the signal with a PLL, but then you once again have to AC couple it, or detect coded levels or something.And meanwhile, all the propagation delays and filtering and detection and decoding, either delays your signal, or reduces its bandwidth or noise floor. Which puts you at a disadvantage, when used in a feedback loop.This is just one example, concerning a few common types of optoisolator components; but it's illustrative of other methods. Anything that has a wave mechanism and a transducer, applies!Electric-electric transducers (i.e., electromagnetic coupling) work from DC (sensing electric or magnetic field) to AC to beyond-light: at low frequencies, we have cored transformers; at high frequency, air core transformers and antennas; at optical frequencies, photodiodes, mixer crystals, and weird quantum stuff; at high energies, scintillators (downconverting the problem to an already solved optical problem, heh) and various particle detectors. (Subatomic particles in turn being another wave we can work with, though with much less ease outside the vacuum chamber!)- Acoustic transducers ranging from motors ("DC") to loudspeakers, piezos, and weird physics (phonon) stuff. Self-contained cases include the "piezo transformer", more of an acoustic resonant network with electrical terminals.- You could even do uh, like, gravity waves on the surface of water... not that you'd have any meaningful bandwidth.- Or gravitational waves, which we can receive right now, but not that we'll have any meaningful way to generate them until we're a few levels up the Kardashev scale...So -- hopefully this has given you some ideas as far as directions to continue researching. No idea if all the possibilities have been made into patents, or any kind of publication even. There are surely some ideas just too bad to bother enumerating, but there are a lot of combinations; who knows if your idea is among them or not.As for commercialization, I suspect you'll have a hard time beating plain old monolithic or hybrid circuits; and photonic circuits are, well they've been in experiments for years, but I don't think anyone's yet commercialized a CPU with optical paths onboard or whatever? The main reason, I suspect, APEX amps generally have poor specs, is they just don't need to be much better? They're pretty specialty, and mainly used for piezo drivers. There are, or have been, a few specialty applications for higher voltages, and high bandwidth -- CRT drivers were a great example, using several 1GHz+ 100V transistors, or ICs to the same effect. But with CRTs obsoleted, you don't see much of them anymore; for that matter, the high current pulsed types that plasma TVs used, either.There are relatively few places a discrete circuit has any advantage left over modern components, even when the fit is relatively poor (i.e. requires several chips to implement). Not that they can't be found; I claim tohave one myself, not that it's a very important thing, and it's certainly not compact at that. It could be beaten by an IC performing the same function -- handily, no doubt about it. It just so happens that nothing available (at least, last I checked) can implement the same function while consuming less overall supply current.Tim

author: Berni
author_rank: Super Contributor
timestamp: February 17, 2021, 01:43:47 pm
content: My Keithley 617 electrometer from somewhere in the 1980s or so and uses a trick using transistors to float the supply rails of a 15V supply opamp along for the ride to give it 100V of output swing along with also amplifying the output for more current.As far as patents go it doesn't really matter if you invented it or not, as long as you are the first to get a patent granted for it. That parent doesn't magically protect your idea from being copied either. It just gives you legal ground to sue someone using it in order to force a licensing payment out of them or make them pay compensation for stealing your idea. So unless you are prepared to sue everyone on a hair trigger, then all the patent is going to do is show everyone your idea.Coming up with such circuits is the job of electronics engineers. Sometimes you just need a circuit that does something special that no easily available chip does, so you fire up LT Spice or <insert your simulation tool of choice> and try throwing together some analog black magic to do the job. But some engineers are employed just to come up with neat circuits like this, this is what people like the brilliant Jim Williams did. His employer LT did not hide his brilliant designs, but instead had him write it up and release it as a application notes to get nice engineer aimed advertising out of it.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 17, 2021, 03:26:58 pm
content: Quote from: flowib on February 17, 2021, 08:36:02 amQuote from: flowib on February 17, 2021, 08:36:02 amThese sound like the non-obvious claims that you would use for a patent so you may have already given too much away to the public record.Getting a patent is expensive and you would need one for each country that you want to stop someone else manufacturing and selling in. Your profile shows you are in the EU. You have to pay a fee for each country in the EU. Then you certainly need the US. China is very difficult. Note, that having a patent in, say, the US, not only stops a company selling your patented product in the US but also from manufacturing it in the US for sale in any country.I recently got a US patent. The process cost me about $30K. To get EU patents would have been about $100K. I know I don't have pockets big enough to stand up to someone if they violate my patent. It doesn't matter, though, because there are only about 6 companies who make anything remotely similar. I'm in negotiations to sell my rights. But I'm talking about a low volume device that sells for $50K with an 80% margin, not a high volume component for $0.01 each with 1% margin. Or, even worse, a non-tangible item like a circuit design.Oh, and it takes a long time. I filed in March 2017 and the patent issued June 2020.EDIT: searching patents is not as simple as it seems. But here's one I found from 1969 in less than 10 minutes based on your description:QuoteYou need to spend a lot of time reading about patent searches and how the examiner conducts searches. The examiner would certainly find this example and argue that the idea of replacing physically connected feedback components with optical ones is obvious. That's the death of your application.EDIT 2: I recently just finished giving testimony as an expert witness in a patent litigation trial related to semiconductors. Each side has spent at least $10M. The legal arguments are around subtleties of the patent language, including how someone of ordinary skill in that particular field would have interpreted "accurate measurement". The actual invention seems irrelevant.

author: fourfathom
author_rank: Super Contributor
timestamp: February 17, 2021, 04:27:48 pm
content: How does one profit from a novel circuit idea? Here's how it works for most people:Be employed at a company with a budget and business plan that encourages you to submit patentable designs for consideration.As part of your regular job, design something that is sufficiently useful and unique.Work with the company's patent attorneys, get your patent filedStick around long enough to see the patent grantedCollect a nice plaque and a cash bonus (typically somewhere between $1 and $1000)Use your demonstrated patent-skills when negotiating for a higher salary.Put your plaques on your "ego wall", and your patents on your resumeThis might sound a bit cynical, but patents are usually way more valuable to a big company (or a start-up) than to an individual. Big companies use their patent portfolio when attacking, defending, or negotiating with their competitors. This is high-stakes stuff with high legal fees.I've got well over a dozen patents, hardware and software, some individual but more jointly. All are held by the company I worked for at the time, or by an acquiring company. Some of these patents are for quite clever designs (if I say so myself), and others are pretty mundane. I don't think any of these patents by themselves would prevent a competitor from designing around them, but they add value to the company as bargaining chips if nothing else. If I had tried to patent these as an individual, it would have cost me way more than I could have ever gained from holding them, and the cost of finding and prosecuting patent infringers would have been prohibitive.Of course if your patent covers a design that is so groundbreaking that it enables a multi-million dollar venture, and is so airtight that it can't be cost-effectively designed around, then what I said above doesn't apply. It can happen, but it's pretty unlikely.

author: penfold
author_rank: Frequent Contributor
timestamp: February 17, 2021, 04:36:07 pm
content: Quote from: flowib on February 17, 2021, 08:36:02 amRegardless of patentability your alternative, the reality is that you would need to be able to manufacture it for significantly less than an apex amp ($400 a chip?) which (ignoring the mix of semiconductor technologies you would have to employ on a single substrate to get the size down and performance up) would mean huge volumes, which unfortunately would mean creating a need for it. A lot of the actuator control applications are being superseded by PWM type controls and a lot of the mainstream need for a 350V opamp doesn't really *need* it to be an "opamp" and a few transistors normally meet the performance specs quite well, they just use the APEX amps because they're very easy to work with and cheaper than the engineering time of developing and validating a new solution... if you include the physical size they are also a very "cheap" service spare... the individual cost of an APEX amp may be high, but it can be very cost effective to design with them.If you have prototyped and tested such a circuit and it meets your intended specifications, I would recommend looking into discussing with companies who build products for its "target applications", its very tough getting to speak to the right person and there's a lot of research to go into it as I'm sure any freelancers on here will testify.

author: mawyatt
author_rank: Super Contributor
timestamp: February 17, 2021, 04:51:20 pm
content: I've been issued over 30 US patents and been an expert witness in patent litigation, so have some relevant background. Within the last year a couple of my patents regarding new type semiconductor technology have been infringed in widespread use throughout the world. I'm retired now and contacted the company that the patent is assigned with (previous employer), they elected not to pursue litigation due the timeline and cost involved. An individual has little chance of being successful patent litigation because of cost and timeline, infringing companies will string the case out trying to deplete the individual financial resources. Even companies like my prior employer often elect to not pursue litigation because of what's involved. Companies do use patents as bartering tools tho, exchanging rights rather than $, probably some tax benefit I guess.Along with the good advise from others consider getting a copyright rather than a patent, this is lower initial cost and generally easier to prosecute.If you decide to invest in a patent, do a very diligent search for prior art, as this is the first line of defense in litigation. Also, do not exclude anyone that contributed to the concept, and do not include anyone that did not contribute. Both of these will cause the patent to be nullified. A large international company I was employed with long ago included department heads and managers on patents to help themselves have a better looking "portfolio", well this action nullified the patents!!In the US getting a LLC might be a good idea, this doesn't cost much and might help to license and even defend the patent in case of infringement since a company rather than an individual is involved. If the patent turns out to be really beneficial and with a large $ upside, getting investors involved can help push this to market and possibly getting the LLC acquired by a larger company. Be careful with venture capital investors, and get legal advice on ownership and rights, they are known for investing in small companies and/or new ideas, and when the company is acquired the original inventors end up with very little reward.Anyway, good luck with your idea.Best,

author: flowib
author_rank: Contributor
timestamp: February 17, 2021, 10:10:01 pm
content: Thanks for all the input, i guess my idea is dead in the water. I'l likely just pot it up and use it for some high voltage stuff, makes a fun little circuit to tinker with.I'm going through a rough time personally, the jobs i can get don't match my capabilities. And my capabilities don't match the jobs i really want.I assumed it was novel, but i needed a reality check. Thanks for that, i have a predisposition to get carried away sometimes. That and i need to grow up knowing there is always someone smarter than me.I wanted to cross couple two floating output buffers to provide smooth class A-B transition, and indeed run a pair of floating supplies for the buffers, buffers would be analogous to the internals of LH0002, Id bias the frond end of the buffers up so that it swamps most of the miller feedback from some beefy external FBSOA optimized fets.Add a couple of INA105's over two resistors near the output node, and feed back into a floating differential front end. Mix it all together using a Fet-BJT cascode on the front end of the buffers and get like 100-200K BW that way, perhaps more if i can run it on the edge of stability.Nothing fancy and its only real benefit over the stuff apex makes is lower production costs and higher dv/dt limits, but i doubt that is really needed. HCNR200 is what i had in mind for the proof of concept feedback amp.It would make a fun power supply project that's for sure. If you think it is interesting anyway, il post some schematics for folks to shoot at and perhaps make it open source.Yeah, il stick to making stuff for lazy engineers, think of Linear mosfet driver bricks or something among those lines. I have found you can get the encapsulations for 30 cents or so. Order some boards from JLC have them populated by them with some basic actives and passives, Send them over to a company that focusses on potting.Another fun idea i had was to build a "Brick" with a isolated I2C on the input that transmits two analog setpoints to two open loop comparators (U, I)that control a basic buffer stage capable of driving unlimited external capacitive loads. Perhaps add a LIA130 to the mix to sense the voltage over the pass element and add the ability to control an external flyback switcher that way. In other words : Linear power supply in a box. The up/Down voltage divider would have a number of pins you can short together to set the gain voltage gain. And for lazy people it will all run from a 10-35V DC input bus.Thanks for pulling me back to earth.

author: KE5FX
author_rank: Super Contributor
timestamp: February 17, 2021, 11:20:13 pm
content: Quote from: JohnnyMalaria on February 17, 2021, 03:26:58 pmIn reality, the examiner will rubber-stamp the application and let the courts sort it out (see below.) The patent office runs open-loop, with no incentive whatsoever to vet the claims, argue endlessly with applicants, or to perform anything more than the most cursory prior art search. That may have been how it once worked, but all you have to do is look at some of the patents being granted nowadays to understand that a minimum of QA effort is being expended.In their defense, the examiners would probably plead overwork. I'm sure the USPTO is managed and funded about as well as most Federal agencies. None of this lameness started with Trump, but it certainly didn't end with him either.QuoteWe're in the wrong business, all right...

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 18, 2021, 12:25:22 am
content: Quote from: mawyatt on February 17, 2021, 04:51:20 pmThat's interesting to know. I've seen that quite a few times as well...

author: mawyatt
author_rank: Super Contributor
timestamp: February 18, 2021, 12:30:48 am
content: Quote from: flowib on February 17, 2021, 10:10:01 pmHang in there, you'll find something that fits your skills and that you like. Remember you can only be really good at things you like, so you'll find something that will allow you to shineQuoteIf you feel comfortable showing the schematics this will help with feedback on your concepts from the folks here.Knowledgable engineers thattruelyunderstand analog/RF and semiconductors are not common these days since younger folks have been lured to the Dark Side (Digital)So good luck and hang in there, things will work outBest,

author: mawyatt
author_rank: Super Contributor
timestamp: February 18, 2021, 12:39:36 am
content: Quote from: SiliconWizard on February 18, 2021, 12:25:22 amThis was from a company that should have known better since they had won a long ~10 year battle on the auto-focus technology used in cameras, eventually collecting likely ~$1B total in awards (triple damages award) and royalities. Lucky for them the invention was not diluted by additions or exclusions!!Best,

author: mawyatt
author_rank: Super Contributor
timestamp: February 18, 2021, 12:54:20 am
content: Quote from: KE5FX on February 17, 2021, 11:20:13 pmThat's for sure!!Legal fees are indeed ridiculous, but unfortunately I believe here in US we have the highest % of lawyers per capita and with the lack of value added in the long term this becomes a burden on overall creativity and productivityBest,

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 18, 2021, 01:35:22 am
content: I don't quite get all of that from a brief description, but it reminds me of a design I thought up a long time ago:https://www.seventransistorlabs.com/Images/Power_OTA2_Sch.pdfOperating principle is, everything's a CCS. With bootstrap or isolated power (note V1 and V4!) the MOSFETs can have local driver stages that convert an input current to a gate voltage, with source current feedback. A diff pair at the front starts everything off, steering a reference current (Q3) dependent on input voltage; hence, power OTA (operational transconductance amplifier).Never did build it, but the simulation has some interesting traits. Bandwidth is high, like 10MHz. But phase shift is also high, so it's not stable closed-loop nearly as high -- I think like 800kHz, I forget. Possibly some improvement could be made in the current mirrors and drivers to pull that back, though I'm not sure how much bias current might have to be spent in the process. (A monolithic solution should be able to solve all those problems, likely reaching even higher frequencies; again, I suspect the problem is there's just not enough application for them to bother designing one.)Heh, these days I wonder if I'd just apply RF amp techniques and put in coupling transformers or something. Gates take a lot of power to drive fast, they aren't all that capacitive up there -- not power MOSFETs at least. That would have to be some kind of split path design, where high frequencies are fed-forward through the transformers, and a typical feedback circuit handles low frequencies including DC. PITA to equalize split-band designs like that, but eh.Tim

author: penfold
author_rank: Frequent Contributor
timestamp: February 18, 2021, 02:14:37 am
content: Quote from: flowib on February 17, 2021, 10:10:01 pmThis thread turned very dark and very dissuasive incredibly quickly! Don't be put off by that, its always worth building something testable and seeing how it compares with current products.Even relatively slow HV amplifiers come up quite frequently in physics-ey sorts of areas, so it is well worth doing some research on target applications. Such companies do tend to be centred in quite specific locations of the world, so permanent jobs aren't abundant world-wide, but these companies are often open to freelance/contract workers - so that's something to consider especially if you have a few tested designs under your hat (they don't even necessarily need to be commercialised).

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 18, 2021, 02:24:20 am
content: Patents are weird things and writing them even more so, especially if you are used to writing scientific material.The key to getting a patent is to act totally and utterly surprised that your idea worked. If you explain how you studied other people's work, figured out some theories etc, then you will be admitting it was obvious based on the information publicly available at the time.In one of my patents with a previous employer, there is the classic phrase, "Surprisingly, we have discovered that..." rather than "I used my expertise in my scientific field to...". In other words, "We didn't have a clue what we were doing but bugger me if we didn't come up with this. Patent please!"

author: penfold
author_rank: Frequent Contributor
timestamp: February 18, 2021, 03:07:16 am
content: Quote from: JohnnyMalaria on February 18, 2021, 02:24:20 amI believe that's also they key to a Nobel prize... "I spilt this on a lab bench... look what happened"