3 ms·
I assume this is the technology Apple is already using in their custom silicon, and why there was that fairly recent story of a hospital where Apple devices fai
by w0mbat 8y ago
I assume this is the technology Apple is already using in their custom silicon, and why there was that fairly recent story of a hospital where Apple devices failed in the presence of helium leaked from their MRI installation.
- ohazi 8y agoApple is/was using silicon mems resonators, which is basically a fancy tuning fork on flexures cut out of silicon. This technology ("bulk acoustic wave") sounds like surface acoustic wave, but perhaps with the vibration mode being through the bulk material rather than just the surface.
- makomk 8y agoIt also seems to fill a different niche from the MEMS resonators Apple are using. Those are ultra-low-power 32KHz oscillators for keeping time in standby mode, but the CC2652RB still relies on an external quartz crystal for that, perhaps because this tech is even more power-hungry than the already too power-hungry high frequency quartz oscillator it replaces.
- abainbridge 8y agoSounds like it is slightly higher power. From the article: > Asked if there is any tradeoff by integrating a BAW resonator in the wireless MCU package, Wong noted a potential power delta at about 2% — “a couple of hundred microamps.” He called it “a reasonable tradeoff, [considering] its benefits outweigh [it].” But, I guess if you can invest the money and area you saved by not having an external crystal and buy a 2% bigger battery, which is probably a net win.