#RaspberryPiPico silicon teardown time!

Board as received optical + x-ray images
Inspecting package. X-ray shows bond wires easier after removing thermal slug
Thermal slug removed w/ HCl + H2O2
Decapped to show copper bond wires connecting die to package pins. Initially used only nitric acid which destroyed copper bond wires (last image). Fixed by switching to mixed nitric + sulfuric acid
Zoomable top metal die image: https://t.co/MXqDBvNgqG
@Raspberry_Pi marking it's turf
B0 => chip revision. On every layer? A chip I worked on did this and unfortunately when we fixed a bug on a *different* metal layer we didn't want to remake the masks with the text. Thus "B1" chips were mislabeled as B0!
M8 => eight metal layer chip. Higher metal layers are coarser to carry more power and reduce manufacturing costs. You can also see M7 and M6 marked
Copper bond wires were eaten by nitric acid leading little dimples where they used to be attached to the bond pads
Several unused power pads. Possibly breaks out internal core voltage for debug / test
Time lapse etching chip layers
This area wasn't 100% etched, leading to vibrant blue/purple from SiO2 thin film interference
1) 20x air vs 2) 60x oil objective: 60x has higher resolution but lower depth of field, making the image appear different. Ex: although the lower left splotch is large, it's only visible in the 60x image. I might take SEM images later for better resolution
Transistors arranged into standard cells form the majority of the digital logic. This includes both the CPU and the digital portion of most peripherals
A few different I/O showing logic, ESD protection, etc between the top metal and transistor layer. A number of different I/O IP blocks are used. Would be interesting to match them up to the datasheet for analog functionality like ADC, USB, etc
Memory, probably the boot ROM
SRAM is scattered throughout the die. By analyzing the memory sizes and comparing to the datasheet it might be possible to guess what some of these are for
CMP fill is added to unused areas to keep polishing more even when preparing for the next layer. As such, it looks like it was omitted on M8 (top metal) but is found on other layers
That's all for now. Hope you enjoyed and let me know if you want more information on something!

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Iโ€™m torn on how to approach the idea of luck. Iโ€™m the first to admit that I am one of the luckiest people on the planet. To be born into a prosperous American family in 1960 with smart parents is to start life on third base. The odds against my very existence are astronomical.


Iโ€™ve always felt that the luckiest people I know had a talent for recognizing circumstances, not of their own making, that were conducive to a favorable outcome and their ability to quickly take advantage of them.

In other words, dumb luck was just that, it required no awareness on the personโ€™s part, whereas โ€œsmartโ€ luck involved awareness followed by action before the circumstances changed.

So, was I โ€œluckyโ€ to be born when I wasโ€”nothing I had any control overโ€”and that I came of age just as huge databases and computers were advancing to the point where I could use those tools to write โ€œWhat Works on Wall Street?โ€ Absolutely.

Was I lucky to start my stock market investments near the peak of interest rates which allowed me to spend the majority of my adult life in a falling rate environment? Yup.
๐™Ž๐™๐™–๐™ง๐™ž๐™ฃ๐™œ ๐™ข๐™ฎ ๐™ฌ๐™ž๐™จ๐™™๐™ค๐™ข ๐‘พ๐’๐’'๐’• ๐’ƒ๐’† ๐’”๐’–๐’“๐’‘๐’“๐’Š๐’”๐’†๐’… ๐’Š๐’‡ ๐’•๐’๐’Ž๐’๐’“๐’“๐’๐’˜ ๐’– ๐’“๐’†๐’‚๐’… ๐’•๐’‰๐’† ๐’”๐’‚๐’Ž๐’† ๐’”๐’•๐’–๐’‡๐’‡ ๐’Š๐’ 50๐’Œ ๐’˜๐’๐’“๐’Œ๐’”๐’‰๐’๐’‘ ๐’๐’“ ๐’”๐’๐’Ž๐’†๐’๐’๐’† ๐’Ž๐’‚๐’๐’‚๐’ˆ๐’Š๐’๐’ˆ ๐’š๐’๐’–๐’“ ๐’Ž๐’๐’๐’†๐’š ๐’˜๐’Š๐’•๐’‰ ๐’”๐’‚๐’Ž๐’† ๐’๐’๐’ˆ๐’Š๐’„
Simple and effective way 2 make Money


Idea 1:- Use pivot level like 14800 in case of nifty and sell 14800straddle monthly expiry (365+335) exit if nifty closes on daily basis below S1 or above R1

After closing below S1 if it closes above S1 next day or any day enter the same position again vice versa for R1

Idea2:- Use R1 and S1 corresponding strikes multiple
Incase of R1 15337 take 15300ce
N in case of S1 14221 use 14200pe
Sell both and hold till expiry or exit if nifty closes below S1 or above R1 around closing
If the same bounces above S1 and falls below R1 re-enfer same strikes

Use same criteria for nifty, usdinr and banknifty

(This is must)Use this margin rule for 1lot banknifty pair keep 4Lax margin
For nifty one lot keep 3Lax
For usdinr 100lots keep 4Lax

I bet you if you do this on consistent basis your ROI will be more than 70% on yearly basis.

Couldn't explain easier than this

Criticisms are most welcomed.