March 2013 – EEJournal

An AC-Biased Microphone

March 28, 2013

I’ll round out the last of the things that caught my attention at this year’s ISSCC with a proposal and implementation of an AC-biased microphone. This is done based on projections that the biasing resistor for a traditional DC approach will head into ridiculously high territory – teraohms and higher.

The team, from NXP and Delft University, lists a number of problems that this causes.

The connection between the MEMS die and the ASIC can easily pick up stray electrical noise due to its high impedance, meaning expensive packaging is … Read More → "An AC-Biased Microphone"

Close Enough?

by Amelia Dalton

March 27, 2013

Not long ago, in our coverage of 3D vision, we discussed time-of-flight as one of the approaches to gauging distance. Even though it and the other 3D vision technologies are gunning for low-cost applications, it’s easy, at this point, to view them as exotic works in progress.

Well, time of flight is now being put to use for the most prosaic of duties: making sure your cheek doesn’t accidentally hang up on you.

Of course, our phones … Read More → "Close Enough?"

Harvesting the Smart Meter

by Kevin Morris

March 26, 2013

Smart meters represent a major infrastructural change in our energy delivery industry. It’s gone smoothly in some places and has met with fierce resistance in others.

The promise is that we will receive more detailed information about how we use power, allowing us to make smarter decisions.
The gray zone is that the power companies can actually come in and adjust our energy usage once a full smart grid is in place.
And the dark zone is that the energy companies are making money selling the personal data so that … Read More → "Harvesting the Smart Meter"

The Worst Two Answers

by Bryon Moyer

March 26, 2013

You’re an upstanding product marketing guy, and you want to validate your company’s product ideas with customers and potential customers. So you go get in front of them (not always easy – that’s when you appreciate your best salesguys with their Rolodexes (Rolodices?) and relationships…).

You sit down in the meeting room, smiles and handshakes and coffee all around, and you pitch your wares.

The best answer you could ask for would be something like, “Awesome! I want one now! I’ll help fund the development … Read More → "The Worst Two Answers"

Gravity Leaking

by Bryon Moyer

March 25, 2013

I recently had a wide-ranging discussion with Kevin Shaw, CTO of Sensor Platforms. It originated out of this nagging thing I had going on in my head about what can be done exclusively with accelerometers. Early thoughts on the topic stimulated my whimsical figure skating article, but my curiosity hadn’t been satisfied.

The gist of my thinking was that, while, in general, you need an accelerometer and a gyroscope to establish both direction and orientation, if you were in a fixed … Read More → "Gravity Leaking"

Dry Etch Edges Wet

by Amelia Dalton

March 20, 2013

Two announcements have come out recently regarding dry etch systems. Now… dry etch is nothing new. Although it is newer than wet etch, which is still being used. And, as they say, therein lies the rub.

The first announcement came late January regarding a new system shipping from Memsstar. Their focus was on MEMS, and, in particular, on reducing yield failures due to stiction. There are two pieces to this move.

First, they note that wet etch processes must be followed by a wash to clean out all of the etchant and resulting groddy … Read More → "Dry Etch Edges Wet"

20 to 14: Less Bad Than You Thought?

by Kevin Morris

March 19, 2013

Conventional wisdom should suggest the following points:

Each new process node affects all layers
Moving to FinFETs will be a big change for designers

Turns out, according to EDA folks (Mentor and Cadence, to be specific), neither of those is true.

The backend of 16/14 (hereinafter referred to as 14 because I’m lazy) – the upper metal layers and such – will be the same as 20 nm. In fact, in this view, the easiest way to describe the 14-nm node is as a 20-nm process with FinFETs instead of … Read More → "20 to 14: Less Bad Than You Thought?"

Lightweight Embedded Multicore Task Management

by Jim Turley

March 14, 2013

The Multicore Association has released the latest of its multicore management APIs. The first such API they released was MCAPI, which allows data to be communicated throughout a potentially complex heterogeneous embedded multicore environment. The next was MRAPI, which deals with the management of resources, allowing virtual extension of scope beyond what an OS would provide in a single process.

This time it’s MTAPI, for managing tasks. Now& … Read More → "Lightweight Embedded Multicore Task Management"

Teasing Apart FBAR Loading and Temperature Effects

by Jim Turley

March 13, 2013

We hear stories of a not-so-distant future when we can wave our tricorder-like devices around and detect all kinds of substances that might be in the air. One of the ways sensors like this can work is by having a resonating body: when a substance adsorbs on the surface, it changes the mass, thereby changing the resonance frequency.

The problem is, however, that temperature also affects the frequency, and it’s actually pretty hard to calibrate that out of the system. Using a reference resonator or a complex software algorithm is possible, but, according to a … Read More → "Teasing Apart FBAR Loading and Temperature Effects"

Tools vs IP

by Jim Turley

March 12, 2013

All of the major EDA companies have had IP. Synopsys started with DesignWare before IP was a real concept; Mentor had IP associated with consulting for several years; Cadence has made a couple of acquisitions – notably memory – to bolster its internal IP efforts.

But the early products of these groups were typically lower-level IP – particularly I/O protocols. Not having to plough through hundreds of pages of a complex protocol spec was an attractive thing – assuming you were willing to trust your vendor to get it right or you had some way of … Read More → "Tools vs IP"