editor's blog
Subscribe Now

What Might Make an Accelerometer More Robust?

Last month STMicroelectronics announced a new accelerometer “engineered to withstand stresses of modern mobile life.” They see those stresses arising from increasingly thinner phones and the mechanical and thermal challenges they cause. They called out board bending as a particular challenge to the mechanical integrity of the works inside the accelerometer package.

So how do you improve the mechanical structure of the accelerometer to do this? First, it helps to realize that there are two structures in ST’s accelerometers. One operates in-plane and provides both x and y acceleration information. A separate structure is used for the out-of-plane z axis acceleration. On older models, these two structures were set side by side.

To illustrate how things might be improved, they made reference to stability in an airplane, even though the comparison can’t be taken too literally. If you want the smoothest ride in the plane, you sit in the middle, between the wings. Especially to the extent that the middle has the least stress and that stresses radiate out from that, there’s more disturbance (bumpiness) at the extremes – the wingtips and nose and tail – than in the middle.

It turns out that the z-axis accelerometer is the most sensitive, so improving it was a goal. So they moved it to the middle of the die layout rather than having it off on one side. And where would the x/y structure go if the z structure is hogging the middle? Symmetry is achieved by splitting the x/y structure and putting one half on either side of the center z structure. The two halves become the “wings.”

The other improvement was to double the number of anchoring points on the z structure from 2 to 4. This reduced the stresses on those points, making them less subject to failure.

You can find more details on the performance of this acceleromete

Leave a Reply

featured blogs
Jul 25, 2025
Manufacturers cover themselves by saying 'Contents may settle' in fine print on the package, to which I reply, 'Pull the other one'”it's got bells on it!'...

featured paper

Agilex™ 3 vs. Certus-N2 Devices: Head-to-Head Benchmarking on 10 OpenCores Designs

Sponsored by Altera

Explore how Agilex™ 3 FPGAs deliver up to 2.4× higher performance and 30% lower power than comparable low-cost FPGAs in embedded applications. This white paper benchmarks real workloads, highlights key architectural advantages, and shows how Agilex 3 enables efficient AI, vision, and control systems with headroom to scale.

Click to read more

featured chalk talk

Improving the Cockpit Computer using Companion Microcontroller
Sponsored by Infineon
Companion microcontrollers are a vital element of today’s complex automotive designs. In this episode of Chalk Talk, Matthew Goodavish from Infineon and Amelia Dalton investigate how the architectural evolution in automotive design has encouraged the need for companion microcontrollers, the role that safety islands play in the development of these systems, and the core system benefits that companion MCUs bring to these kinds of designs.
Jul 10, 2025
21,164 views