The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
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The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
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Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#2It is interesting that its possible to produce chips at this price for more than a short time period. Also that they are all basically PIC clones or variants speaks to the core competency of these companies is manufacturing and operational efficiency, not MCU design.
I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say less than 10K gates). Would these manufacturers pick up that design and run with it, making variants and parts that people could buy? It would get Microchip off their back (several have been sued apparently).
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#3These have their uses.
A friend who frequently does contract development in the toy space has (or at least used to have) a favorite go-to MCU that costs under $0.06 in bare die. It is essentially a 6502 with 100 bytes of RAM and a metric butt-load of mask-programmable ROM. It was originally designed for greeting cards. He has designed it into toys.
It is hard to use, you need a dev kit and a good relationship with the distributor to get the documentation. It only makes sense in high-volume products, since it comes as passivated bare die so assembly requires a die-bonder and expoxy encapsulation depositer.
Not for everyday use. But as my friend says: “You haven’t lived until you have spent an entire afternoon arguing over $0.05 on the BOM.”
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#4These have their uses. A friend who frequently does contract development in the toy space has (or at least used to have) a favorite go-to MCU that costs under $0.06 in bare die. It is essentially a 6502 with 100 bytes of RAM and a metric butt-load of mask-programmable ROM. It was originally designed for greeting cards. He has designed it into toys. It is hard to use, you need a dev kit and a good relationship with th…
Great story, thanks for sharing. I for one pretty much constantly live the life he alludes to at my company bomquote.com. In China, we actually negotiate in increments of ~1/6th of a penny.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#5Around the year 2000, a PIC 12C508A was about 1 Dutch guilder @ 5000 pcs.
Today, Mouser lists 1 pcs @ € 0,908, 100 pcs @ € 0,863.
The guilder/€ is 2,20371 ( muscle memory ).
The MCUs in the article are 12C508A class, one is an actual clone.
So for ~ € 0,80 at quantity, the 12C508A currently costs about 1.75 guilder. 20 years later.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#6It is interesting that its possible to produce chips at this price for more than a short time period. Also that they are all basically PIC clones or variants speaks to the core competency of these companies is manufacturing and operational efficiency, not MCU design. I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say…
> I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say less than 10K gates). Would these manufacturers pick up that design and run with it,
I have done that thought experiment many times. I have a ISA that I sketched out many years ago but never did anything with. Often, I have thought it would be a real hoot to put up a working Verilog model on Github with a public domain license just to see if I could bait somebody in China into manufacturing it for me so that I could buy it off Digi-Key :)
Of course, the CPU isn't really the value any more. One salesman for an ARM licensee said it best: "Look at the die photos from any of the ARM licensee's. We are all just selling value-added flash." And as far as that goes, it isn't the CPU that drives the part design-in decision. It is having good, bug-free, peripherals in the right mix and a reasonable tool chain.
So the "free CPU design as wild oats" idea has appeal, but it would need an LLVM back-end to go with it, at minimum, and then unencumbered Verilog for a collection of basic peripherals.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#7Some Philips sonicare toothbrushes use(d) a 4-bit microcontroller from an obscure Swiss company. (From memory, since I can't find the EEVBlog video teardown) 52 bytes of RAM, custom size mask ROM, ? Kilohertz clock speed. It makes sense, they just needed a timer for the "2 minutes of brushing is up" feature, and maybe some battery management. It still surprised me that it was worth the hassle to save a few cents, even if they sell millions of the things. They must make insane margins: $80 for a vibration motor and $25 brush refills.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#8It is interesting that its possible to produce chips at this price for more than a short time period. Also that they are all basically PIC clones or variants speaks to the core competency of these companies is manufacturing and operational efficiency, not MCU design. I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say…
> I think a fascinating experiment here would be to invest some time in an unencumbered scalable design that could be implemented very inexpensively (say less than 10K gates). Would these manufacturers pick up that design and run with it, I have done that thought experiment many times. I have a ISA that I sketched out many years ago but never did anything with. Often, I have thought it would be a real hoot to put up…
I think you should still post it to github :-). Agreed on the peripherals as well, I good set of open source peripheral models in verilog would be a useful addition to the mix.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#9Some Philips sonicare toothbrushes use(d) a 4-bit microcontroller from an obscure Swiss company. (From memory, since I can't find the EEVBlog video teardown) 52 bytes of RAM, custom size mask ROM, ? Kilohertz clock speed. It makes sense, they just needed a timer for the "2 minutes of brushing is up" feature, and maybe some battery management. It still surprised me that it was worth the hassle to save a few cents, eve…
Maybe one of these?
https://www.emmicroelectronic.com/catalog?title=&term_node_t...
EM Microelectronics is actually not so obscure. They belong to the Swatch group and are specialized in ultra lower power analog and mixed signal circuit. Obviously, first for watches.
Re: The “terrible” 3 cent MCU – a short survey of sub $0.10 microcontrollers
#10These have their uses. A friend who frequently does contract development in the toy space has (or at least used to have) a favorite go-to MCU that costs under $0.06 in bare die. It is essentially a 6502 with 100 bytes of RAM and a metric butt-load of mask-programmable ROM. It was originally designed for greeting cards. He has designed it into toys. It is hard to use, you need a dev kit and a good relationship with th…
It´s very common to find those chips in cheap home alarm systems.
In Brazil, Holtek has a huge presence in that niche.