Author Topic: EEVblog #971 - Zero Standby Power TV - BUSTED!  (Read 31465 times)

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Offline StillTrying

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #75 on: February 13, 2017, 01:21:50 am »
Seems a pretty small niche....

Perhaps they could run a monthly competition. $500.....
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Online amspire

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #76 on: February 13, 2017, 02:53:57 am »
I think the best thing they could do is some Linear Technology-type application notes, where they pick real problems and solve them with their device.

The truth is with TV's is their standby current is improving, and they can make it even better if the market demands it. My current TV uses 0.3W standby which is under 2c a week of electricity. Using the TV's own standby, I get a remote that only reacts to the correct IR remote handset, and I get features like timed video recording. Why would I want to spend, say, $20 on a device to make my TV work worse and that would save me 70c a year?

They need to talk to developers who have real problems and develop well-designed and explained application notes.

The application notes are a great help to developers, and also they would give a real focus to the promotional efforts. Also, the exercise may reveal that they need further development - they may find they have to have a way to recognize a specific IR signal - not just any IR signal - to be useful in many applications. This feature could be built into the device, or there may be a way that when IR is present, a second IR discriminating chip could be powered-up to identify the IR signal.
« Last Edit: February 13, 2017, 03:55:50 am by amspire »
 

Offline Bristol Energy

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #77 on: February 13, 2017, 03:42:02 am »

There are many, ... a micropower comparator will probably be just fine and draw less than battery self-discharge.
For example
http://www.digikey.co.uk/product-detail/en/texas-instruments/TLV3691IDCKR/296-37910-1-ND/4900957
75nA current draw, 0.9v minimum supply.

If you don't need the threshold voltage as low as 0.6ish a MOSFET will give you near-zero input current.

If you need low threshold, a high-gain bipolar transistor will do that with pretty low input current. (anyone know what the limiting factor is here ? Noise ?)

So that leaves applications that absoutely need both low threshold voltage and low input current, and can't afford the drain of a comparator.
And where you're not worried about a single-source device from a non-mainstream supplier.

Seems a pretty small niche....

Thanks Mike,
I think that describes our niche well.

A single transistor would switch too slowly, when the sensor output gradients are very low, and lock up the system. As the transistor starts to turn on, the load electronics transitions the unwanted logic states too slowly, and a load system gets stuck in a low impedance mode that drains the battery current. So we needed something that works like a power-on-reset circuit.

We use the ZMDI ZSPM4121 if we have 100nA sources, if threshold is not important. 40nA input current. 5.5 max input, 1.2V threshold.

We use the SiLab TS12001 if the threshold is important, 0.78 V, but then you are looking at hundreds of nA input, and only 2.5 V max.

Our IR example would have required hundreds of photodiodes in parallel to turn these devices on.

Our ferroelectret and piezo sensor outputs would collapse to nothing if we used these devices. Once you are down to below square centimetres of active sensor material, it is easy to be in the GOhm output impedance range. If you stomped on the material, then you would overvoltage these commercial detectors.

The RF rectenna needs a very low threshold to get any range. That is why we made another version of this detector with a 0.46 V threshold. If you put your rectenna next to the transmitter, you'd over-voltage a commercial voltage detector. If you protect the input with a zener diode, then the leakage kills your range. We then found, that the 100pA input current of this lower threshold device, made the range worse, so we went back to using our 6pA input device with the slightly higher threshold.

So we need to find which niches require "sensor-driven" approaches, as that seems to be our advantage. These areas need a very low threshold voltage and high maximum input voltage at the same time. Many of these areas probably need sub-nA input current, or it's not realistic with off-the-shelf sensors.  We need a fast switching system to not go into lock up, and we need hysteresis as sensor output gradients can be very slow. Our device does all of this. But what are the applications where a non-sensor driven approach isn't (yet) viable?






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Offline mrpackethead

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #78 on: February 13, 2017, 05:33:29 am »
Personally i think Dave was a bit harsh.. But thats his call, his forum and Blog.   Its his style and its the cynical engineer thing..     The irony is that without daves video i woudl have never known about this, and i now i do.

Its a bit like the 'avoid PCBWAY' thread somewhere else on the forum..  Its probalby sold more PCB's for them than any paid advertsing
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Online EEVblog

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #79 on: February 13, 2017, 07:14:24 am »
Personally i think Dave was a bit harsh.. But thats his call, his forum and Blog.   Its his style and its the cynical engineer thing..     The irony is that without daves video i woudl have never known about this, and i now i do.

A few people have said I was "a bit harsh" and shouldn't have "picked on" students and/or a university team.
My response is several fold:
a) I don't know what people mean by "a bit harsh"? A bit harsh because I actually did a video on it at all?, or a bit harsh in the things I said? If it's the latter then I think I was pretty generous and praised their chip several times. If it's the former, then see the comment below.
b) They aren't students, and this isn't student project. Students may have worked on it I don't know, but that's beside the point
c) This isn't some research paper or research project, I would never "pick on" anything research related or a published paper etc.
d) IIRC they actually invited engineering feedback in their video
e) They very deliberately went public with slick marketing for this thing they are looking to eventually sell . A slick promo video and demo. A slick website blog type page etc. They went to a lot of effort to do all this. It has become a commercial public product and that makes it fair game.
f) They were wrong, and have admitted as much.

What is "a bit harsh" anyway? Because I spoke my opinion? Because I spoke my opinion and I have a big audience? They way I said things? My tone?
Once you put something out for public consumption and comment then you can expect public feedback, especially in the science and engineering community from your peers, it is entirely to be expected.
People expect me to speak my mind (and I don't know anything else), so it's either the video I made, or no video at all.
Should a university team be immune to such criticism? No way.
Should they be able to operate in an all-to-familiar "safe space" these days? No frick'n way.

As for why I did the video, it's obviously not because I wanted to ridicule them or whatever, it's because I saw someone posted it on the forum, watched the videos and thought that was marketing BS.
I thought it would make an interesting video, and I was actually rather careful to praise the chip and just call them out on the obviously marketing BS and the niche application for this, both of which are 100% accurate.

A few people seem to not like it purely because it's a university group, but have no problem when it's a company or Kickstarter etc. I don't get that, they all involve real people with feeling and reputations etc. I make the choice based on whether or not it is fair game. They went public with marketing a commercial product, so it's fair game.
« Last Edit: February 13, 2017, 10:10:27 am by EEVblog »
 
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Offline mikeselectricstuff

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #80 on: February 13, 2017, 09:19:09 am »
Quote
Our IR example would have required hundreds of photodiodes in parallel to turn these devices on.

Our ferroelectret and piezo sensor outputs would collapse to nothing if we used these devices. Once you are down to below square centimetres of active sensor material, it is easy to be in the GOhm output impedance range. If you stomped on the material, then you would overvoltage these commercial detectors.

The RF rectenna needs a very low threshold to get any range. That is why we made another version of this detector with a 0.46 V threshold. If you put your rectenna next to the transmitter, you'd over-voltage a commercial voltage detector. If you protect the input with a zener diode, then the leakage kills your range. We then found, that the 100pA input current of this lower threshold device, made the range worse, so we went back to using our 6pA input device with the slightly higher threshold.
That's exactly the sort of thing you should be featuring in videos & appnotes, not pointless TV demos.
These things are non-obvious to people who haven't worked in this area, so you need to educate potential customers as to exactly what the issues are and why your device solves a problem, and where it has advantages over other solutions.

 
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Offline Bristol Energy

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #81 on: February 13, 2017, 09:42:50 am »
What is "a bit harsh" anyway? Because I spoke my opinion? Because I spoke my opinion and I have a big audience?

I'm enjoying the sensible discussion of our work here on this forum. It's the sort of thing we miss while we're stuck in the lab for years. We are not students, but, apart from me, the team are young researchers. I've re-edited our three videos following your video feedback. Dave was right to say that the TV video was misleading.

Dave, you have a big diverse audience, and that is important, and hard to cater for.
As we have seen from the aggressive comments and under the busted video and our videos, some of your audience take your message as being "I hate the bullshit research that University X is conducting, which is just smoke and mirrors". Not all, but still enough to be scary. Some respected bloggers have suggested there are simple ways of doing what we do, which has been taken as proof that funding is being wasted. Your viewers trust you, and to some, the good message is not coming through, and all our videos, even the RF one, were getting mostly dislikes and aggressive comments, as soon as your video went up. 

I think your message is twofold:
(1) Good: "They have a good research outcome (the chip, not the TV), with good characteristics (datasheet) with no competition (yet) in niche areas (sensor-driven stuff)",
(2) Bad: "They have poor demos because the marketing has made the demo look like the target application (which it is not), and for this apparent application, they have neglected to describe the remaining power drains, by implying wrongly that the total system power was zero, when it was only that of the sensor that was addressed. Their product has narrower use than they are implying, and they need to find the right kind of demos."

So whilst I see that you are saying lots of nice things about our chip (thanks), as you start and end with (2), thousands of viewers don't appear to see (1).

Anyway, I'm taking this all as a good lesson in life, and hope we talk more about the science. No hard feelings.
 

Online EEVblog

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #82 on: February 13, 2017, 10:01:03 am »
Dave, you have a big diverse audience, and that is important, and hard to cater for.
As we have seen from the aggressive comments and under the busted video and our videos, some of your audience take your message as being "I hate the bullshit research that University X is conducting, which is just smoke and mirrors".

I thought I was quite clear in the video (more than once?) that I was not criticising the research, but the marketing and demo example.
Unfortunately it doesn't matter how careful I am in explaining things, even repeatedly, there will be people who will not hear it and will only hear what they want to hear. This happens with almost every one of my videos in some form.

Quote
Some respected bloggers have suggested there are simple ways of doing what we do, which has been taken as proof that funding is being wasted.

The good part about that is that no respected and knowledgeable blogger in the field will say that any research is wasted.
Joe Average though is another unpredictable ball-game.
Well, actually, Joe Average is quite predictable in statistical terms. The bigger the view numbers the wider the "Niceness bell curve" and you start to get the hater outliers.

Quote
Your viewers trust you, and to some, the good message is not coming through, and all our videos, even the RF one, were getting mostly dislikes and aggressive comments, as soon as your video went up. 

Aggressive comments are always regrettable, but unfortunately is the nature of the internet. I did see however that negative comments were there that pre-dated my video.

Quote
I think your message is twofold:
(1) Good: "They have a good research outcome (the chip, not the TV), with good characteristics (datasheet) with no competition (yet) in niche areas (sensor-driven stuff)",
(2) Bad: "They have poor demos because the marketing has made the demo look like the target application (which it is not), and for this apparent application, they have neglected to describe the remaining power drains, by implying wrongly that the total system power was zero, when it was only that of the sensor that was addressed. Their product has narrower use than they are implying, and they need to find the right kind of demos."

That's spot-on.
Of course there was never bad intent in the way I did the video or what I said or the way I said it. As per all my videos, it's just me commenting on what comes to mind on a topic I found interesting.

Quote
So whilst I see that you are saying lots of nice things about our chip (thanks), as you start and end with (2), thousands of viewers don't appear to see (1).
Anyway, I'm taking this all as a good lesson in life, and hope we talk more about the science. No hard feelings.

Thanks. And that's the right attitude to have in these case, and is the way that most people and companies I've criticised have responded. And they have almost always found it ends up being a positive constructive result in the end.
Just coming on this forum and being honest and willing to discuss earns huge points with the community.
As noted above, I don't think there is any way to avoid people taking some things the wrong way.
I hope some good can come from it. As they say, all publicity is good publicity  ;D
 

Offline NANDBlog

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #83 on: February 13, 2017, 10:07:24 am »
OK, we know the following:
Microcontrollers listening to IR signals take microamps of power.
The SMPS in the TV is really inefficient, running at 10% or less.
A typical lithium battery will run a microcontroller for years, and it has the energy to start the SMPS.

So I think we know what to do. Just put a lithium primary battery into the TV and run the standby power from that. Saves a ton of energy, and on the plus side, it will run out of power after years, so you will be forced to buy a new TV, solving planned obsolescence. It also floods the market with perfectly good TVs, which can be repaired with minimal soldering skills. Synergy! I'm quite sure marketing weasels would think this at least.
 

Online EEVblog

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #84 on: February 13, 2017, 10:14:06 am »
OK, we know the following:
Microcontrollers listening to IR signals take microamps of power.
The SMPS in the TV is really inefficient, running at 10% or less.
A typical lithium battery will run a microcontroller for years, and it has the energy to start the SMPS.
So I think we know what to do. Just put a lithium primary battery into the TV and run the standby power from that.

No need to do that, just suck the uA from the mains.
Like I showed in the video:


No need for a battery or harvested power, just an existing well designed integrated low standby SMPS solution.
« Last Edit: February 13, 2017, 10:36:43 am by EEVblog »
 

Offline StuUK

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #85 on: February 13, 2017, 10:26:27 am »
Personally i think Dave was a bit harsh.. But thats his call, his forum and Blog.   

Nope,and personally I'm fed up with overhyped marketing BS coming out of Universities, it puts them firmly in the same camp as everyone else (companies, kick-starters etc) who use deceptive marketing like this, so you get what you deserve. Disappointed that such a good UK university is doing this!
 

Offline jonovid

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #86 on: February 13, 2017, 02:17:16 pm »
it would be totally amazing if the television was cordless and powered itself for 5 yrs without emitting any radiation.  :-DD
But alas micro energy harvesting in AC powered home appliances is all a bit pointless .  But if you can get a 30% energy saving on a 3kw electric stove  or air conditioner design, then good.
« Last Edit: February 13, 2017, 02:33:58 pm by jonovid »
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Offline nctnico

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #87 on: February 13, 2017, 04:10:20 pm »
Even if not immediately identifiable as having any commercial viability in itself, I look at it like research brainstorming - it could spark something brilliant.  This could be some bizarre application that was not immediately apparent, or a stepping stone for someone to develop something else.
I would be stunned if there is not some immediate niche application for this chip, because AFAIK there is not an equivalent "harness energy, trigger output" kind of chip?
Those who don't think there is an app probably just haven't thought hard enough or aren't involved in an area that needs it.
There will no doubt be some out there that see it and go "wow, that is just does what I need for my dooflewinkle project".
Come to think of it. This chip may be interesting for more complex (microcontroller) based circuits. In those you usually have to leave the microcontroller powered in order to wait for a wake-up event. This means there will be a regulator and other circuitry on all the time and currents quickly add up to the 100uA ball park even if you switch off power to parts of the circuit. A chip which can make do with the power coming from (for example) a piezo based push button could eliminate all the tedious (software) work of putting a microcontroller to sleep and use cheaper parts which don't need to be ultra low power.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline ScottK

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #88 on: February 13, 2017, 06:50:21 pm »
Anyway, I'm taking this all as a good lesson in life, and hope we talk more about the science. No hard feelings.

It is a good lesson, and better learnt before vast sums of money have been invested by people who've got unrealistic expectations. I saw this happen far to often during my foray into the world of angel capital, where exuberant entrepreneurs waxed rhapsodic about their cool new ideas to potential investors with no technical background.

Your technology is impressive, and you have described just why that is so. To power up, glitch free, on picowatts of power is terribly difficult. That said, is the greatest potential for the technology in chips, or as a tool set for chip designers? You've already mentioned interest in more complex functions, that makes sense to me.

I was completely turned off by the marketing video, but I'm equally intrigued by your explanation of the benefit of reducing the loading on sensors by orders of magnitude. Most of us are not accustomed to working in the world of fA and pA and so we may not be aware of interesting things you can do there, like get 0.6V from a small area photodiode illuminated by a remote control 3 meters away. While you're at it, discuss PCB manufacturing techniques to keep leakage from ruining your day, I'm sure you've encountered this in your research and know it'll stop customers dead in their tracks if they don't address it.

 

Offline mikeselectricstuff

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #89 on: February 13, 2017, 07:47:18 pm »
Come to think of it. This chip may be interesting for more complex (microcontroller) based circuits. In those you usually have to leave the microcontroller powered in order to wait for a wake-up event. This means there will be a regulator and other circuitry on all the time and currents quickly add up to the 100uA ball park even if you switch off power to parts of the circuit. A chip which can make do with the power coming from (for example) a piezo based push button could eliminate all the tedious (software) work of putting a microcontroller to sleep and use cheaper parts which don't need to be ultra low power.
You'd be doing a pretty poor job if it was taking that much. Any decent MCU with a low- power regulator can easily get well below 10uA in a sleep mode which can be woken periodically by watchdog, 32K crystal and external edge.
 
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Offline nctnico

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #90 on: February 13, 2017, 08:33:55 pm »
Come to think of it. This chip may be interesting for more complex (microcontroller) based circuits. In those you usually have to leave the microcontroller powered in order to wait for a wake-up event. This means there will be a regulator and other circuitry on all the time and currents quickly add up to the 100uA ball park even if you switch off power to parts of the circuit. A chip which can make do with the power coming from (for example) a piezo based push button could eliminate all the tedious (software) work of putting a microcontroller to sleep and use cheaper parts which don't need to be ultra low power.
You'd be doing a pretty poor job if it was taking that much. Any decent MCU with a low- power regulator can easily get well below 10uA in a sleep mode which can be woken periodically by watchdog, 32K crystal and external edge.
With a single MCU on a 3V coin cell you can easely reach sub uA currents but that is not always the case. In some circuits it is not just the MCU (which usually draws more than the datasheet promises because you have to leave more stuff on to make it all work) but also the regulator (think about using a battery >>5V) and other circuitry as well. In those cases it all adds up to a whole lot of (worst case) current.
« Last Edit: February 13, 2017, 08:35:42 pm by nctnico »
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Offline mikeselectricstuff

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #91 on: February 13, 2017, 08:48:47 pm »
Come to think of it. This chip may be interesting for more complex (microcontroller) based circuits. In those you usually have to leave the microcontroller powered in order to wait for a wake-up event. This means there will be a regulator and other circuitry on all the time and currents quickly add up to the 100uA ball park even if you switch off power to parts of the circuit. A chip which can make do with the power coming from (for example) a piezo based push button could eliminate all the tedious (software) work of putting a microcontroller to sleep and use cheaper parts which don't need to be ultra low power.
You'd be doing a pretty poor job if it was taking that much. Any decent MCU with a low- power regulator can easily get well below 10uA in a sleep mode which can be woken periodically by watchdog, 32K crystal and external edge.
With a single MCU on a 3V coin cell you can easely reach sub uA currents but that is not always the case. In some circuits it is not just the MCU (which usually draws more than the datasheet promises because you have to leave more stuff on to make it all work) but also the regulator (think about using a battery >>5V) and other circuitry as well. In those cases it all adds up to a whole lot of (worst case) current.
There are plenty of regulators which only draw a few uA quiescent current, some with inputs up to 24v ( e.g. Holtek HT7150)
 If anything else is drawing power you should be turning it off.
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Offline trophosphere

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #92 on: February 13, 2017, 09:10:06 pm »
With a single MCU on a 3V coin cell you can easely reach sub uA currents but that is not always the case. In some circuits it is not just the MCU (which usually draws more than the datasheet promises because you have to leave more stuff on to make it all work) but also the regulator (think about using a battery >>5V) and other circuitry as well. In those cases it all adds up to a whole lot of (worst case) current.

Along with shutting down external circuits when not in use, I will sometimes use this circuit to expand Vin range with a regulator such as this (20nA quiescent current) for very low power applications if a battery with a high voltage source is needed. Usually one would choose a battery whose nominal voltage is closer to your system's operating voltage  and use a boost converter if a higher voltage is required as you can turn that off as well when not needed.
 

Offline Bristol Energy

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #93 on: February 13, 2017, 10:29:58 pm »
I wonder, how does it react when powering a device off? For example, suppose it is a device which saves log files to flash storage during the shutdown sequence (like with some entry level NAS devices, and routers), does the circuit wait for the load to drop below a certain threshold, or does it simple toggle on when one pulse is given, and then toggle off when another pulse is given?

Our detector power-gates the TV into standby mode.

We have used a passive OR logic function to power-gate the regular receiver circuit, TV processor etc. In this way, either the sensor-driven detector or the TV's processor can hold the system on. So when the TV is on, it can keep itself including the regular receiver circuit on, and when it shuts down, it does so because this regular circuit has received the off signal. The TV shuts down as usual. Once the processor is in its listening-only mode, the signal from the processor goes low, and now it's up to our detector to keep the system on. But at that point, you're probably not pressing the on-button of the remote, so the OR has no input, and the whole system shuts down.

One problem for us was that the demodulation is carried out by the TV's processor which takes a long time to boot. We would need a microcontroller to start up quickly (e.g. TI uC with sub-100us startup) so that demodulation happens quickly. Then we wouldn't need our two button presses.
Another problem is that the filtering out of ambient light needs to be passive. We don't know much about optical filtering, we are using off-the-shelf parts.

Also, as I have added to the second half of the re-edited video, we need to working on passive ways of filtering out ambient light. Resonant techniques and anti-parallel diodes using ideas from this patent: US 4982081 A are giving us decent results. Does anyone know of other techniques?
« Last Edit: February 14, 2017, 08:11:33 am by Bristol Energy »
 

Offline nctnico

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #94 on: February 13, 2017, 10:52:48 pm »
With a single MCU on a 3V coin cell you can easely reach sub uA currents but that is not always the case. In some circuits it is not just the MCU (which usually draws more than the datasheet promises because you have to leave more stuff on to make it all work) but also the regulator (think about using a battery >>5V) and other circuitry as well. In those cases it all adds up to a whole lot of (worst case) current.

Along with shutting down external circuits when not in use, I will sometimes use this circuit to expand Vin range with a regulator such as this (20nA quiescent current) for very low power applications if a battery with a high voltage source is needed. Usually one would choose a battery whose nominal voltage is closer to your system's operating voltage  and use a boost converter if a higher voltage is required as you can turn that off as well when not needed.
Did you check the datasheet on that 20nA regulator? It says typical and no maximum. Also the regulation is piss-poor. I wouldn't design this thing in IF I could look past the 'Microchip' brand.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline trophosphere

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #95 on: February 13, 2017, 11:04:58 pm »
Did you check the datasheet on that 20nA regulator? It says typical and no maximum. Also the regulation is piss-poor. I wouldn't design this thing in IF I could look past the 'Microchip' brand.

Yup. Checked it. Used it multiple times. Current is about 10ish nA for many projects for all possible operating scenarios so no problem at all. Regulation is fine for powering a microcontroller, sensors, and a bluetooth transceiver from a battery. You don't have to go for the most stable and accurate component every time - such as people that purchase the latest and greatest and in the end it doesn't make a difference. Design to your given specifications with a sane overhead and everyone is happy.
 

Offline Bristol Energy

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #96 on: February 13, 2017, 11:05:54 pm »
While you're at it, discuss PCB manufacturing techniques to keep leakage from ruining your day, I'm sure you've encountered this in your research and know it'll stop customers dead in their tracks if they don't address it.

We lacquer the board as soon as they are made or get them done professionally. Or you'll get soon get GOhms between tracks and 100s of pA leaking away.
We might do a video on low power measurements, I think people might find that useful.
 
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Online EEVblog

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #97 on: February 14, 2017, 12:09:46 am »
We might do a video on low power measurements, I think people might find that useful.

Please do, there is a distinct lack of ultra low power measurement and technique videos.
 
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Offline CJay

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #98 on: February 14, 2017, 10:40:33 am »
Top of my head, 'sealed for life remote controls', a piezo film deforms when a button is pressed and powers up the micro which does the 'usual' remote control thing before powering down to zero power when the user has finished pressing buttons.

Wide area distributed environmental sensors that wake and gather data when energised by tuned circuit (RFID already does this but can't manage the wake on sensor value change bit AFAIK)

I see the idea as more 'proof of concept' and it could be sold as IP to a microcontroller manufacturer for the first zero power standby product?

A little more thought would/could produce more ideas but I think while it's far from a useless product, it's more of a solution looking for a problem, one of those neat ideas which is intellectually good but perhaps too niche or before its time?

Perhaps it could be used as proof of concept as I can see it might be useful for integrati

M0UAW
 

Offline digsys

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Re: EEVblog #971 - Zero Standby Power TV - BUSTED!
« Reply #99 on: February 14, 2017, 11:25:32 am »
Quote from: trophosphere
... I will sometimes use this circuit to expand Vin range ...
But that increases Vmin, negating the LDO advantage. What DO do you see?
Hello <tap> <tap> .. is this thing on?
 


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