10 ms·
Semiconductors are more than just processors and GPUs
- blueflow 5y agoFun fact: Solar cells and the LEDs are the same element. If you wire up a solar cell like an LED, it glows dimly in infrared. QA uses this to diagnose dysfunctional wafers.
- magicalhippo 5y agoSteve Mould had a video[1] about this a couple of years ago where he shows a small solar panel lighting up. [1]: https://www.youtube.com/watch?v=6WGKz2sUa0w https://www.youtube.com/watch?v=6WGKz2sUa0w
- agumonkey 5y agoIs it possible to have a light / emw battery ?
- SECProto 5y agoSpeed of light is fast, even if possible you'd be looking at a lot of conversion losses. It'd be like trying to use a wire as a battery because power has to travel from one end to the other
- thehappypm 5y agoI’ve heard of materials that can slow down the speed of light propagation. Imagine you can slow the speed of light to a crawl. You shine a huge amount of light into this material, which has a mirror on the other side. Before your light arrives back at the source, swap it for a mirror. You’ve now got a huge amount of light energy trapped.
- SECProto 5y agoOkay, I imagined it. Converting electricity into light is inefficient (maxing out around 44% [1] excluding ballast losses), and converting light into electricity is also inefficient (topping out at 47%[2] efficiency). So you'd end up with a battery that stores energy at extremely low efficiency (less than 21% combined), relying on a hypothetical exotic material that can slow light transmission to ~0.00000001c, assuming you don't mind using a hypothetical box that is 1km long, and you can shine the light and replace the light with a mirror in <1 second. And that's before even accounting for the fact that perfect mirrors do not exist, so you'd be losing another 0.1% of remaining energy with every cycle (i.e. every second) Or you could buy a lithium-ion battery off the shelf today at 95% round trip efficiency and low self discharge. [1] https://en.wikipedia.org/wiki/Luminous_efficacy#Lighting_efficiency https://en.wikipedia.org/wiki/Luminous_efficacy#Lighting_eff... [2] https://en.wikipedia.org/wiki/Solar_cell_efficiency https://en.wikipedia.org/wiki/Solar_cell_efficiency
- thehappypm 5y agoAwesome analysis. Another piece to think about is density. Even with these losses.. how much energy can a material hold in terms of pure light? Is there a limit to how much light can pass through a material? And I wonder if you could slow the light down even further, maybe 2 or 3 more orders of magnitude..
- grishka 5y ago> use a wire as a battery Isn't that one of the possible uses for superconductors tho?
- nofunsir 5y agoIf you shine a light at a mirror, then quickly point the mirror at another mirror, it will keep a dark room lit for a couple hours.
- DaniFong 5y agointeresting thought, and i think so :) dm's open at @daniellefong on twitter
- maxbaines 5y agoThat's fun and super interesting, going to read more on it.
- altcognito 5y agoHey, Electroboom just covered this: https://www.youtube.com/watch?v=l2y-w9aS98k&t=617s https://www.youtube.com/watch?v=l2y-w9aS98k&t=617s
- reportingsjr 5y agoYep! This is why solar panels typically have another diode wired in series with them, so they don't draw/waste power and emit light at night! In the solar world they call it a blocking diode.
- kken 5y agoNo, there is no series diode. There is an antiparallel diode to prevent solar cells from turning current into heat when they are shadowed.
- reportingsjr 5y agoA quick search of the term in my post instead of just saying no would have been useful. https://www.sciencedirect.com/topics/engineering/blocking-diode https://www.sciencedirect.com/topics/engineering/blocking-di...
- deelowe 5y agoMany electronics work that way. Motors can also generate electricity. Inductors can create or sense magnetic fields. Resistance is generally temperature dependent. Etc.
- petschge 5y agoEverything is as temperature sensor. Some elements also measure other signals.
- user_7832 5y agoJust made be realize, when you cook, the food is basically a temperature sensor. (Burnt) Toast is a great example.
- parenthesis 5y agoYou can use headphones as a microphone, or a (dynamic) microphone as a loudspeaker.
- ______-_-______ 5y agoThis is my favorite one. Being on stage and hearing music come out of your mic is a hell of a trip.
- jbay808 5y agoAlmost any high-efficiency energy transformation is reversible, in fact!
- amelius 5y agoI just hope my TV can't be used as a camera ...
- drdeca 5y agoWell, pairing the TV with a light sensor in a fixed location, and like, having the tv alternate between a sequence of different patterns, and recording how this changes the reading of the light sensor, and assuming that the room is otherwise dark, uh, apparently can be used to produce an image of the room as if taken from the location of the tv and illuminated from the position of the light sensor?
- Unklejoe 5y agoDoes the same go for Peltier plates and thermocouples?
- jbay808 5y agoYes, thermocouples can work as heat pumps, and Peltier elements can work as thermocouples.
- iancmceachern 5y agoThere are actually flow meters that make use of this. They heat the thermocouple using itself, then switch back to using it as a thermocouple and measure the rate of heat dissipation and correlate that to flow rate.
- tomn 5y agoHere's a video of a circuit I made which flashes an LED, using only power collected by the LED: https://youtube.com/watch?v=BM7VDOoFIWI https://youtube.com/watch?v=BM7VDOoFIWI The LED is the component on the left; there's a very dim flash (pretty much just the black die turning red) at around 11s, then every few seconds. I can't remember exactly how it works... I think there's two capacitors charged up to the voltage of the LED in parallel through high-value resistors, and a circuit that shorts the +ve of one to the +ve of the other to put them in parallel. It only just works at a very specific light level. IIRC some of the transistors are used as very low leakage diodes rather than transistors, as the regular diodes I had we're too leaky.
- blueflow 5y agoNow this is the most impressive thing i've seen today! Especially because its made out of discrete components. Kudos.
- tomn 5y agoThanks! I'm not sure what integrated components you could use for this, as anything useful would probably use more current than the LED can provide.
- mrtksn 5y agoCool, it's a self powered light meter. The more light there's in the environment the more frequent the blink. Maybe can be adjusted to have less frequent, shorter lasting but more powerful flash!
- giantrobot 5y ago> Maybe can be adjusted to have less frequent, shorter lasting but more powerful flash! This should be called a Goku circuit. Kaaaamaaaaikaaaaaa.
- CamperBob2 5y agoWell, almost anything will glow dimly (or brightly) in infrared if you shove enough electrons through it.
- NikolaNovak 5y agoI used to be a professional computer geek on weekdays and professional photographer on weekends; and 20 years on, it still blows my mind the similarities between the materials and manufacturing of the CPU doing heavy work in my laptop and the sensor gathering pixels in my camera :O
- genericone 5y agoTransistors! E.g. EPROM (memory type chip) is typically deleted by shining a uv light on the actual silicon die, through a uv transparent quartz window in the final packaged chip. edit: fixed EEPROM -> EPROM
- moltke 5y agoI read somewhere that some people used EPROMs and decaped Ram chips as digitizers for early computers.
- 01100011 5y agohttps://hackaday.com/2014/04/05/taking-pictures-with-a-dram-chip/ https://hackaday.com/2014/04/05/taking-pictures-with-a-dram-... Yeah I remember a friend of mine back around '90 wanted to try it out. I can't remember if it was using DRAM or EPROM memory though. I want to say it was called 'ramra' or 'ramera'.
- analognoise 5y agoThat's not an EEPROM. That's an EPROM. The first E in EEPROM is ELECTRONIC - i.e. you use a voltage (or a control word) to indicate that you would like to erase the device. Also, EPROMs are extremely vintage. They were replaced by EEPROMs - the first of which came out in 1977. That's an... extremely vintage example.
- genericone 5y agoFixed And thanks for the info, I don't have direct experience dealing with EPROM and I had conflated EEPROM and EPROM together in my mind, but a quick google search quickly reveals my inadequate knowledge, which has now been updated, even if only good enough for trivia.
- dragontamer 5y agoGood overview, but he's missing one of the coolest applications of semiconductor / photolithography. MEMS. Micro-electromagnetic systems. The most common MEMS I can think of is the comb sensor, used for accelerometers in all of your cell phones. https://www.memsjournal.com/2010/12/motion-sensing-in-the-iphone-4-mems-accelerometer.html https://www.memsjournal.com/2010/12/motion-sensing-in-the-ip... The MEMS sensor for an accelerometer is quite simple. Take the nearest comb and smack it against a desk: you'll notice that the comb vibrates in one direction. Now hook up two combs and interleave their teeth together so that they're barely touching. When they touch, an electrical signal is sent through them to sense when they touch. Add differently sized teeth, the larger the spacing the more acceleration is needed before they activate. (EDIT: Looks like the iPhone MEMS uses capacitance... similar concept though, the capacitance changes based off of how far away these teeth are from each other and you can measure that using college-level electronics) Finally, have these teeth rotated in all directions, so that you can sense all the directions in one little device. -------- MEMS are about using the physical properties of object, but just making these small physical objects really, really, really tiny thanks to the magic of photolithography. You can see this literal comb structure by looking at any accelerometer under a microscope: https://memsjournal.typepad.com/.a/6a00d8345225f869e20148c7030795970c-pi https://memsjournal.typepad.com/.a/6a00d8345225f869e20148c70... ------ If the accelerometer is too difficult for you to understand, the "beginner MEMS" is gears. https://www.sandia.gov/app/uploads/sites/145/2021/11/1-1.jpg https://www.sandia.gov/app/uploads/sites/145/2021/11/1-1.jpg You can make any shape you want with modern chip-making tools. The "shape" most people want is a transistor (gate, drain, source). But in many ways, a teeny-tiny gear is simpler to think about. The practical applications of micro-scale MEMS (gears, combs, springs, etc. etc. ) is somehow harder to think about than computers, so there aren't very many practical MEMS around. But still, practical MEMS help remind us that all of these chip-making tools exist in the real, physical world. Albeit at a very small scale.
- rcxdude 5y agoCapacitive sensing is the norm for consumer accelerometers: you generally don't want surfaces making contact and especially sliding past each other in MEMS in practical applications because the surfaces will tend to stick to each other or wear extremely quickly (MEMS gears are a neat trick but you won't find them in any product using MEMS because they last a few minutes of operation at best).
- swamp40 5y agoI spent most of the day yesterday chasing down crosses for P-Channel FETs. They are all GONE. No stock of anything (except the crappy ones, super-tiny packages, high Vgs(th) or high Rds(on) and other leftovers). I've never seen anything like this, it's kind of frightening. Like walking into a grocery store and seeing the aisles all EMPTY except for a few scraps. I don't even know where they all went. It's not like you need a TSMC slot to make a FET. And whatever you look up, Chinese brokers have 10K-50K pieces of them for $25 each. Don't know what to think of that, either.
- sitzkrieg 5y agoive been trying to find some power mosfets to certain specs for a BOM for.. over a year!
- exmadscientist 5y agoA year? It seems like you should have been able to come up with something within a year? Unless it's an exotic or you have tight targets for cost or supplier qualification. If you're willing to share the original part number, I'm curious as to what FET could cause so much grief.
- zargon 5y agoIt's not TSMC capacity that's the problem. It's the large nodes that make everything except cutting-edge processors. Nobody builds a new large-node fab, but demand for large node components keeps rising.
- nwellinghoff 5y agoYou nailed it. Most chips you use everyday come from the large node fabs. Maybe we should build some more.
- mywittyname 5y agoDemand for semiconductors only recently exploded. In 2016, annual growth suddenly tripled for a few years. It's hard to know if this rate of growth is sustainable, or if it will fall back to "normal" again soon.
- philipkglass 5y agoCPUs and GPUs account for more dollars spent than solar cells, but solar cells account for most area/mass of semiconductor devices made today. A gigawatt of solar cells represents about 5 square kilometers of silicon wafers at 20% light conversion efficiency. The world installed 183 gigawatts of solar PV in 2021, almost all of it based on silicon wafers: https://www.pv-magazine.com/2022/02/01/bloombergnef-says-global-solar-will-cross-200-gw-mark-for-first-time-this-year-expects-lower-panel-prices/ https://www.pv-magazine.com/2022/02/01/bloombergnef-says-glo... That's in the neighborhood of 915 square kilometers of wafers. Silicon for solar has risen meteorically over the past 20 years. https://www.pv-magazine.com/2021/10/26/whats-next-for-polysilicon/ https://www.pv-magazine.com/2021/10/26/whats-next-for-polysi... Until the early 2000s, demand for polysilicon (often simply referred to as “poly”) was dominated by the semiconductor industry, which required a fairly steady 20,000 to 25,000 metric tons (MT) per year. But semiconductor demand for poly was quickly outpaced by PV as the solar industry began to grow rapidly, from a rounding error at the turn of the millennium to almost half of global polysilicon demand by the middle of the decade. ... By the end of 2013, the manufacturing cost of polysilicon had tumbled to below $20/kg among industry leaders. Meanwhile, capacity had grown from less than 50,000 MT per year in 2007 to over 350,000 MT per year by 2013. Polysilicon capacity at the end of 2021 was in the neighborhood of 700,000 metric tons, with more big expansions on the way. The extra 350,000 metric tons added since 2013 is almost entirely for solar.
- hateful 5y agoI almost always think of all the things on breadboards (e.g. in the second picture on the page). But it's probably because of all the games I played had those kinds of things in their technology thumbnails. Or maybe it was because I was alive when Radioshack existed. most recently: https://dyson-sphere-program.fandom.com/wiki/Microcrystalline_Component?file=Microcrystalline_Component.png https://dyson-sphere-program.fandom.com/wiki/Microcrystallin...
- kragen 5y agoThose are diffraction-grating colors, not thin-film-interference colors.