Silicon Labs Shrinks Wireless SoCs to Extend BLE to Miniature Devices
13 comments
·March 20, 2025nimish
arghwhat
You wouldn't use a chip antenna if you're that tight on PCB space.
A trace at the circumference of the PCB, or a wire antenna that only take up space for the solder joint would do.
TheSpiceIsLife
Fractal antenna!
xnzakg
With the right pcb design you could use this to sneak in an entire microcontroller while making it seem like it's just an antenna, wild
bboygravity
Limiting factor for what application?
The battery/power supply alone is going to be at least an order of magnitude larger in volume.
Joel_Mckay
"The battery/power supply alone is going to be at least an order of magnitude larger in volume."
Indeed, people do use rechargeable lithium batteries like the 50mAh CR322 (22mm by 3mm) or smaller CR311, but these would only be able to handle a 11mA EFR32BG29 output load for a few hours at most... Yet in a mostly dormant power save mode YMMV =3
inhumantsar
if we're talking about a device that only needs centimeters worth of range and spends most of its time in deep sleep, those 50mA could last quite a while.
jtrueb
Is this not just a worse version of the nRF52 and nRF54 lineup? Larger size, fewer hardware peripherals, lower radio sensitivity. What is the new thing for this chip?
zokier
It's bit silly to say that they shrink SoC when the new chip is exactly the same package as their previous generation from few years ago.
gleenn
I don't immediately see a picture of the actual chip to get a reference size bybitself, that that chip inside the tooth is pretty wild. I wonder how you would even begin to power electronics within such a space. Or perhaps this is more of a marketing level of graphics.
metaphor
From the article:
> The BG29 chips will be available in 5 mm × 5 mm QFN and 2.6 mm × 2.8 mm WLCSP form factors
That "wireless oral health monitor" example is a concept from Lura Health[1] that integrates a marginally smaller BG27 (2.3mm x 2.6mm WLCSP)[2].
[2] https://www.silabs.com/applications/case-studies/small-bluet...
opello
The second link isn't exactly forthcoming on the battery technology used, but at least says:
> and its power consumption is low enough that the device can last from six months to a year on a battery of the equivalent size
The average "width" of the first mandibular molar from this article[1] is 5.1-5.2mm. It sure would be interesting to see a CAD model of the design inside the module on the band. The graphics from the posted article vs. the first link above are also a bit different, making it even harder to infer much I think.
null
The antenna is the limiting factor IIRC, the smallest module available is this thing: https://www.fdk.com/cyber-e/electronic_components/module/ble... which has the antenna as a slot in the package itself.