I 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.
It's my current living nightmare. Endless treadmill of:
1. Our contract manufacturer calls in a panic no longer able to obtain/was shorted on a shipment of part XYZ. XYZ is increasingly becoming random "jellybean" parts like MOSFETS, oscillators, to slightly-more-complicated but not "fancy" stuff like serial transceivers, USB stuff, NOR flash, load switches. TI is the bane of my existence currently.
2. Search for a drop-in or near drop-in replacement. There are none, because that's what everyone's doing.
3. Search for alternative designs. Maybe the component is in distributor's stock (Digikey, Mouser, Newark, etc), maybe it's not.
4. Test the alternative design. By the time I receive parts, prototype, test, guess what? Can't get those parts anymore. Go back to step #2.
5. Fall behind on all of my other NPD responsibilities. Stress, burnout, acceptance. Lament not going into another engineering field. Feel bad about my midwest metro area compensation in comparison to a bunch of Silicon Valley SWEs on website.
It'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.
Switched-mode power supplies (SMPS) are eating components at an alarming rate. The increase in high-efficiency DC and battery-powered products has really changed that market.
shouldn't these shortages lead to older equipment/processes being dusted off and brought back online?
7nm or whatever state-of-the art processes may be important for certain latest electronics, but I'm guessing there are many components that could use 10 year-old or more semiconductor fabrication processes.
I had your exact same problem a few weeks ago trying to get P-channel FETs and ended up with the SI2301CDS-T1-E3 which Mouser has just 143 left (which you can't believe).
Same with USB-UART bridges; zip, nada, nothing. I found some Cypress parts a few weeks ago, and I should consider myself lucky.
I won't order PCB until I have all reels of parts on my desk.
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.
Many electronics work that way. Motors can also generate electricity. Inductors can create or sense magnetic fields. Resistance is generally temperature dependent. Etc.
CPUs 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:
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.
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 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.
Capacitive 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).
- very tiny microphones for smartphones (speakers are harder)
- Digital Micromirror Devices (DMDs): arrays of tiny mirrors used in most projectors
- microfluidics ("lab-on-a-chip" stuff for fast disease testing, DNA sequencing, cell manipulation, etc)
And a couple other semiconductor applications:
- LCD/LED screens (monitors, phones, laptops, etc) (these are made on a glass surface instead of a silicon wafer but use the same basic manufacturing techniques)
- laser diodes (laser pointers, CD / Blu-ray players)
I 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
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.
I 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.
swamp40|4 years ago
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.
bluesquared|4 years ago
1. Our contract manufacturer calls in a panic no longer able to obtain/was shorted on a shipment of part XYZ. XYZ is increasingly becoming random "jellybean" parts like MOSFETS, oscillators, to slightly-more-complicated but not "fancy" stuff like serial transceivers, USB stuff, NOR flash, load switches. TI is the bane of my existence currently.
2. Search for a drop-in or near drop-in replacement. There are none, because that's what everyone's doing.
3. Search for alternative designs. Maybe the component is in distributor's stock (Digikey, Mouser, Newark, etc), maybe it's not.
4. Test the alternative design. By the time I receive parts, prototype, test, guess what? Can't get those parts anymore. Go back to step #2.
5. Fall behind on all of my other NPD responsibilities. Stress, burnout, acceptance. Lament not going into another engineering field. Feel bad about my midwest metro area compensation in comparison to a bunch of Silicon Valley SWEs on website.
6. GOTO #1
zargon|4 years ago
nickff|4 years ago
geph2021|4 years ago
7nm or whatever state-of-the art processes may be important for certain latest electronics, but I'm guessing there are many components that could use 10 year-old or more semiconductor fabrication processes.
sitzkrieg|4 years ago
ComputerCat|4 years ago
kragen|4 years ago
unknown|4 years ago
[deleted]
madengr|4 years ago
Same with USB-UART bridges; zip, nada, nothing. I found some Cypress parts a few weeks ago, and I should consider myself lucky.
I won't order PCB until I have all reels of parts on my desk.
blueflow|4 years ago
If you wire up a solar cell like an LED, it glows dimly in infrared. QA uses this to diagnose dysfunctional wafers.
tomn|4 years ago
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.
deelowe|4 years ago
reportingsjr|4 years ago
In the solar world they call it a blocking diode.
magicalhippo|4 years ago
[1]: https://www.youtube.com/watch?v=6WGKz2sUa0w
CamperBob2|4 years ago
Unklejoe|4 years ago
altcognito|4 years ago
https://www.youtube.com/watch?v=l2y-w9aS98k&t=617s
maxbaines|4 years ago
philipkglass|4 years ago
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-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-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.
dragontamer|4 years ago
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-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/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
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|4 years ago
alted|4 years ago
- hard drive read/write heads (the platters are debatable)
- inkjet printer nozzles (this is why making a DIY inkjet printer is nontrivial)
- air pressure sensors (e.g., for car tires)
- precise frequency filters for smartphone wireless communication
- oscillators (https://news.ycombinator.com/item?id=18340693)
- very tiny microphones for smartphones (speakers are harder)
- Digital Micromirror Devices (DMDs): arrays of tiny mirrors used in most projectors
- microfluidics ("lab-on-a-chip" stuff for fast disease testing, DNA sequencing, cell manipulation, etc)
And a couple other semiconductor applications:
- LCD/LED screens (monitors, phones, laptops, etc) (these are made on a glass surface instead of a silicon wafer but use the same basic manufacturing techniques)
- laser diodes (laser pointers, CD / Blu-ray players)
- many quantum computers
HPsquared|4 years ago
_moof|4 years ago
mardifoufs|4 years ago
https://youtu.be/iPGpoUN29zk
NikolaNovak|4 years ago
genericone|4 years ago
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
hateful|4 years ago
most recently: https://dyson-sphere-program.fandom.com/wiki/Microcrystallin...
kragen|4 years ago