Editors' Blog

Mag Sensor for Watch Compass

Continuing with the series of Sensors Expo conversations, I had a chance to discuss a couple of topics with Memsic (one of which we’ll talk about in a future entry). Today we’ll look at their magnetic sensor, which relies on AMR – anisotropic magneto-resistance.

Currents generate magnetic fields, but with AMR, the difference in direction by the field generated by current and some external field will impact the resistance of the material. Current is generally run at an angle in stripes of … Read More → "Mag Sensor for Watch Compass"

Converging by Construction

by Bryon Moyer

Chip design has always consisted of a series of loops. Do something, check the effects, fix things, check again, and hopefully converge on a solution. A big part of the focus of EDA tools developers has been to make each of these passes faster and reduce the number of passes.

One of the critical things that has to be checked at the end of each layout pass is that the layout meets the design rules. A couple years ago, the DRC-checking part started … Read More → "Converging by Construction"

It’s the Details

by Bryon Moyer

A couple of years ago I was stunned to find myself jazzed by batteries. I mean, how mundane can you get? A battery is a battery is a battery, right? And we keep hearing that there are needs for major breakthroughs to enable better electric cars and such, and yet those breakthroughs haven’t been obvious. Probably because they haven’t happened; development has been incremental, not a step function.

But something about Infinite Power Solutions’ story grabbed my curiosity and … Read More → "It’s the Details"

Scribblers want their forecasts

by Bryon Moyer

Scribblers want their forecasts to be right; it makes them look brilliant. Any company that fails to make the scribblers look good deserves to be punished. How dare they?

[/sarcasm]

I suppose a more reasoned argument would be that the share price prior to the announcement had already factored in a higher number, and that reality forced the value down to factor in the real number. If we wish to assume rationality…

… Read More →

Teenage scribblers

by Amelia Dalton

Many years ago the British Chancellor of the Exchequer (Finance Minister) referred to financial analysts as “teenage scribblers”. And they don’t seem to have grown up. Yesterday Samsung announced that it expected profits for the second quarter of the year to be yet another record at between $8.2 and $8.5bn. That’s right – eight point five billion dollars. $1.20 for every man, woman, and child on the face of the planet in just one quarter. The company’s shares promptly fell by 2.8%. That’s right as well – record profits and the company’s … Read More → "Teenage scribblers"

Sensing the Turn

by Bryon Moyer

This is yet another note regarding the innumerable sensors on display at the recent Sensors Expo. But rather than jumping straight in, let’s explore a problem: one akin to “shaft encoding.”

Those of you controlling precision motors and such know far better than I do about keeping track of the rotating shaft of the motor. By tracking marks on the shaft, the electronics can keep track of the position of the shaft (not to mention speed and other related parameters).

… Read More → "Sensing the Turn"

IP Block Verification

by Bryon Moyer

If you design SoCs, then you use IP. Lots of it, probably. From different companies, some perhaps even from your own company.

And the good news is, it’s all perfectly documented – pins, registers, timing, everything. Right? So you know that just fitting it all together will give you a correct-by-construction design. Right?

Yeah… and then you wake up.

In fact, the RTL implementation may deviate from the spec, or there may be holes in the spec, or the black-box RTL may have invisible surprises. It’s enough to make you run back … Read More → "IP Block Verification"

Software Development is Failing

by Dick Selwood

I wanted to share this, which I found on the System Safety Mailing list: https://lists.techfak.uni-bielefeld.de/mailman/listinfo/systemsafety

Martyn Thomas has enormous experience in implementing computer systems and was the founder of Praxis a company, now part of the Altran group, that became “internationally recognised as a leader in the use of rigorous software engineering, including mathematically formal methods.” He wrote in a thread about software:

I recall a lecture given by Dijkstra in 1973. A member … Read More →

Separating You from Your Phone

by Bryon Moyer

In high-school physics class, we did an experiment. It’s so crude by today’s standards, that I feel like something of a fossil as I recall it, but here goes. We had a ticker-tape kind of thing that would make a mark on a paper tape as you pulled the tape through. It marked at a constant frequency, so if you pulled the tape faster, the dots were farther apart. So dot spacing became a measure of speed.

The experiment consisted of two parts. In the first, we held the tape and walked a … Read More → "Separating You from Your Phone"

Simpler CDC Exception Handling

by Bryon Moyer

For static timing analysis, it’s a concept that goes back years. You get a bunch of violations, and then you have to decide which ones represent false paths or multi-cycle paths and create “exceptions” for them. Tedious.

Well, apparently formal analysis can have the same issue. Only here they’re referred to as “waivers,” according to Real Intent. If you run analysis and get a long list of potential violations, you have to go through the list and, one by one, check them for “false positives” and mark … Read More → "Simpler CDC Exception Handling"