new 30MHz to 300MHz switcher - worlds smallest laptop adapter

According to a presentation I saw on licensed inventions from another university (Kirsten Leute @ Stanford), they've taken in 1.6bn in licensing fees since 1971 and get disclosures at higher than a daily basis, and _start_ patent applications on ~50% but they have not had a new high-income winner in about 18 years. The last big one was Google-related (1996 $337m as of 2012- they took some equity which paid off big)... but mostly life sciences/biotech stuff with a couuple of communications/EE inventions. Before 1996 it was every 2-3 years between big hits.

I guess one could speculate on whether the pace of home-run inventions has actually slowed down, or something else is going on.

Best regards, Spehro Pefhany

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OK, my bad, I was optimistic in my 0.1% estimate.

The last big one was

Two things are going on at many universities: a push for patents and a press-release mill.

Web sites, like phys.org and a zillion others, are hungry for content, and the university press departments (which didn't used to exist) are happy to provide it. Every little research paper, which in past years would have died in deserved obscurity, is now announced as a huge breakthrough.

Crowdsourcing makes this trend even more interesting. These goofy press releases can now be quickly monetized if you can generate enough publicity and promises. Tens of thousands of people put up a couple hundred dollars each, and their money fades away over some years, so there's no big noise over it.

--

John Larkin                  Highland Technology Inc 
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

Precision electronic instrumentation 
Picosecond-resolution Digital Delay and Pulse generators 
Custom timing and laser controllers 
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Multichannel arbitrary waveform generators

It's my impression that either from conviction or poor risk/reward conditions, there is less inventing in the US. People are spending time mitigating risk and cost, not seeking it.

OTOH, there's all sorts of opportunity for inventions and synergy--cheap wireless, FLASH, GHz CPU, etc.

Cheers, James Arthur

Okay, I looked at it a little deeper.

I missed on a couple points.

First, the switched capacitor switches aren't low voltage. There are only a few of them, so that doesn't fly. Also, when S1 of Fig. 6 is open, one of the switches S2 has to stand off the entire input voltage. Let's hope S2 never pops!

Second, I figured out the "energy recirculation" -- it's kind of elegant. The charge pump efficiency is improved by charging the series capacitor string *through the synchronous buck*. That way, the series capacitor strings' peak charge current is controlled, avoiding inrush charging losses. That's clever.

In effect, the buck runs off the switched-cap converter's ripple voltage when the cap string is in series, and off the charge pump caps in parallel during the paralleled time.

It also means you don't need nearly as many switched-cap stages to get to the roughed output used to feed the sync. buck.

The VHF aspect is confined to the synch. buck finishing regulator. Its low input voltage allows the use of fast, small geometry devices.

There, I think that's the gist of it.

No galvanic isolation, which might be changed by substitution of a suitable isolated "buck."

Cheers, James Arthur

On a sunny day (Thu, 26 Dec 2013 06:12:13 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :

So then you need that transformer again, and an other synchr. rectifier, a simple diode there would ruin efficiency. May as well go without the cap switches network then...???

Oh, my! A Marx generator run in reverse. Well, lots of possible places things could break down, or just lose energy.

Jon

Exactly, nothing new here, just some one trying to bank on old tech..

Jamie

And, he apparently got $9 million for it! Not BAD! Wish I had great "ideas" like this!

Jon

You need the cap-switch network. The low input voltage into the synch. buck is what produces the other opportunities: 1. the cap-switching reverse Marx generator (thanks Jon!) makes a low, unregulated voltage pretty efficiently. 2. The synchronous buck can use low-voltage, low resistance, low Qc FETs that scream.

The patent suggests running the cap-switcher at, say, 1Mhz, and the synch. buck at 5-100x that.

Ramifications: the low voltage differential into the buck increases the buck's duty cycle, which increases efficiency. Low voltage differential also reduces the inductance needed for a given ripple current, which increases efficiency, reduces volume, and reduces copper losses, which reduces volume even more.

There's usually a fatal flaw. Haven't seen it yet, but it looks fragile--lots of switches have to flip reliably, or you smoke it.

Cheers, James Arthur

I haven't seen the soft-charging of a cap-switcher trick. Nor have I seen using a cap-switcher front-end to a buck switcher, or that people recognized the advantages that flow from that.

I'm not endorsing it mind you, just analyzing.

Cheers, James Arthur (P.S. I've not seen soft-charging in a Marx generator either-- that's a good idea :-)

That one retains an archive of it.

On a sunny day (Thu, 26 Dec 2013 21:42:08 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :

Oh I see lots of problems, this cap switcher, when in series with the buck, may charge smoothly, but then putting those caps in parallel on the next step, would require precise equal caps (so they were charged to the same voltage), else you get big spikes (at that 1MHz) in the switching FETS to equalize the cap voltages, If on chip caps then they could be equal, in any case what would aging do with external caps?

Somebody mentioned we need a multi-voltage multi-current design, to grab that market, that is an other problem here. If not a multi type output you may as well build it into the laptop, and provide a power cord connector.

And the fact that any adaptor I have bought lately (last year) says: "110-230V' may make his chip design a bit more challenging with on chip capacitors and switches.... It should at least stand 240 x sqrt(2) = 340 V DC on the chip input, and as you noticed at least one of the switches sees that full voltage, And that is not counting weird high mains, as may still be present in some places in the UK, UK had 240 V AC.

Yes, the magic [smoke] may become visible at some point

On a sunny day (Thu, 26 Dec 2013 21:47:26 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :

Any inductor in series will do that, look at how flash tube circuits work. the discharge (and what is the difference with charging) is made smooth and lengthened over time by a small L in series, I have used that.

Nor

That last thing is like saying you can get a patent for adding a 7805 after a switchmode. That is just normal practice, regulators in series (of different type) have been used for years.

???? Controlled output voltage, switching caps regulates NOTHING.

He needed a regulator anyway!

I am against patents for these kind of things, maybe you could argue using the inductor of the buck as current limit is new, but using an inductor as current limiter most certainly is not. Now everybody, if that patent is granted, has to pay that club for something any designer could come up with if he spend some time, that is what design is! Make new configurations, make new things with the things you have.

Who gave him the 9 M$ was wrong.

But then again, we are past the age of technology. The whole world is in some illusionary state with media hype and politicians steering their agenda, away from science.

Now we have GlowBallWorming... This is nice to read:

about CO2... so who is right and who is wrong, what is right and what is wrong, you hear what hey want you to hear, you believe what they want you to believe, and actually they know no better, you are a consumer, and when ordered to buy you will, your commercial and news brain wash every so many minutes delivered to you in any way possible.

LOL :-)

Agreed--any cap mismatch produces dV(c), making spikey spikes when switching from series to parallel configuration, same as a conventional charge-pump.

I haven't bothered with any numbers, but I rather doubt they could use on-chip caps. The capacitances and voltages needed are too high. So says my gut, anyhow.

Let's see...if we wanted 60w (input) worth of charge packets at

1MHz at 170VDC input, c=60W/(.5*v^2*1Mhz)= 4nF for the series string, or 12nF each for a string of 3, at 57 volts each.

That would be quite a chip.

Cheers, James Arthur

Of course, we all know that. But I haven't seen the bottom of a series'd string of switched caps terminated in a synchronous buck, specifically to reduce losses in the switch-cap charging and provide a low input voltage to the buck.

You may think it's obvious but the obvious rejoinder is that if a. it's better, and b. obvious, why have billions of laptop adapters been made, without ever using it?

If you were the first one to do it, and no one else had thought of it, that might be patentable too. In 1930. :-)

If it's normal practice, can you point to anyone anywhere that's done it? I can't.

Right, but you're missing the point. He can generate, say, +5v from

+170v with the switched cap thing, so that the switcher can be a 30MHz unit with 10v mosfets. Or +3v and 5v mosfets, etc.

The existing selection of laptop adapters, representing millions of man-hours of design, suggest that no one else came up with it. That's the whole point.

That could very well be. If the thing doesn't deliver, they're screwed. But if they've worked out any defects, it could be a home-run.

It's reasonable to be skeptical, until then.

Cheers, James Arthur

On a sunny day (Fri, 27 Dec 2013 08:58:15 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :

It is the only part of the invention, using the buck inductor to limit the series capacitor charge current and get some extra power, that is 'new' AFAIK.

The way I read the patent is that it attempts to claim all configurations like that, Reminds me of Apple, somebody invented the lock, and Apple patents it as one for lock on a door, one for lock on a window, and one for lock on a cabinet, and one for lock on a car, like touch screen. Abuse of the patent system, and Apple did not even invent the touch screen. They also tried to patent a square box with round corners and what not. I am not a Samsung fan, I critsized them a lot,. but I have 2 Samsung monitors and one big Samsung LCD... if you look at the legislation Apple vs Samsung you see the problem, even 0bama got into it to prevent Samsung imports... Or was it Apple being forbidden. Such a silly game and waste of money, we all ape and try to improve. For my air speed meter I have read many documents and related and not related research in many fields already. And I will use what seems to make the most sense..

Else design becomes impossible, somebody joked a while back Microsoft patented the '0' and '1', well maybe that was just a joke, but they may well go for the sequence 110101 and that is a binary number and now everybody using that will have to help make them rich so they can kill and other Nokia. OK..

The 7805? seen it many times... Used it myself, may even be on my site. usually I get a 12 V switching wall wart and make 5 V for PICs from it with yes, an 7805.

You still need the mains separation, transformer, rectifier in secondary, Would it really be that more efficient then if you used that directly? Did not they get better than 87% already? I did not see any numbers on claimed efficiency by them.

Well, they just gobble up the 9 M$ in research.

Same for the research into quantum computers, the looking for gravity waves, the experiments for break even fusion, and what not, perpetuum energy sources.

Yep, when in the shops, or a chip I can buy, I will congratulate them. Especially if it still works after 5 years. :-)

The legalese annoys me, but I skimmed the claims. They all 'recite' (that's the term of art) a switched-cap front end with a dynamically alterable division ratio, coupled with a conventional switcher that advantageously uses the lowered input voltage, and produces a regulated output.

Seems fair to me, and pretty specific.

Not, not that--have you seen anyone using an adaptible-ratio switched-cap as a front-end to a low-voltage switcher?

He actually does coarse regulation by changing the cap-switching ratios. I skipped that as not very interesting.

I didn't see any efficiency numbers either, but one infers high efficiency from the small form factor, otherwise it'd burn up.

Sounds good.

Cheers, James Arthur

Guys, is it physically possible to transfer energy with just capacitors for isolation?

I know you can send data that way (because it can be encoded with just edges, and providing there isn't too much common mode noise, the edges can be decoded) but I can't see any way to transfer *power* that way.

Inductive components are needed if you want isolation - as in most consumer appliances.

LED lamps don't need isolation and there is a huge amount of work being done in that area.

On a sunny day (Sat, 28 Dec 2013 15:41:39 +0000) it happened Peter wrote in :

Theoretically yes, if your switches have a high enough isolation voltage, you can switch a cap against the input, disconnect it, and the switch against the output.

Using a very high frequency and very low value capacitors, where main voltage sees a high impedance, and the RF a low impedance, maybe. But that high frequency RF can be dangerous too, Something like this; 1nF A ------ ||---- |>|------ + | |

-- mains --- RF oscillator L C load 30 MHz | | B --------||-------------- - 1nF

The 50 or 60 Hz mains will not make it much through the 1 nF, the power from the RF oscillator will.

But getting zapped by a few watt RF will burn your skin.. touch the output here. If you make sure point B is main ground maybe not so much, but mains ground will be a high impedance at RF too.

But I think you can make a simple PCB transformer on dual layer at that frequency, no need for the caps.

But efficiency?

They have modulated LED lights so it sends ethernet packets that you can receive with a photo diode. Should be OK for UDP streaming messages, dunno about the return path.