Digital doesn't always mean better

In our heart of hearts, we want to believe that everything digital is superior to the technology it pushes aside. Consider personal healthcare and simple medical devices, for example. Digital scales offer more consistent readings than their mechanical counterparts, which require constant calibration. Who wants to stick a mercury thermometer in his mouth when a cheap, convenient digital device can do a better and safer job?

Moving up in sophistication, though, you cannot assume that digital is automatically better. Take digital blood-pressure monitors, for instance. I recently purchased one after getting some marginally high readings during my annual physical. The doctor had used a mercury-based sphygmomanometer and advised me to buy a digital unit to record daily readings.

I bought one at Walgreen's and consistently received substantially lower readings than the doctor with his mercury-based sphygmomanometer. Naturally, I wanted to believe my $60 digital device, but, unconvinced that I was out of the woods, I consulted a semiconductor-company executive who was wrestling with the same problem. Surprisingly, he said that digital isn't always a slam dunk.

"I believe that digital is good ... in most things. I started out with a hand-pump stethoscope as my home check. I'd take a reading, then get my wife to put on the steth and take my blood pressure. She'd always get a different number. I think the digital ones are far more consistent, but the quality of the sensor itself is probably the biggest determinant, not the fact that the actual calculations are digital," he wrote back in an e-mail.

I also double-checked his contention that Consumer Reports had rated mercury-based units, such as the one in the doctor's office, as the most reliable. Indeed, they are the most reliable, not to mention the fact that pros who conduct dozens of such tests every week generally operate these units. However, the healthcare industry is phasing out these devices, fearing that the tube housing the mercury could break. Nonmercury manual monitors are also solid performers, as are many automatic and semiautomatic monitors with digital displays, Consumer Reports found.

Other variables influence the accuracy, mostly having to do with how and when someone administers the test. Also, there's a phenomenon known as "white-coat high blood pressure" that describes high readings that occur only in the doctor's office. The best way for me to check my unit's accuracy is to bring the home unit into the physician's office or go out and buy another home unit to compare them side by side. Until then, the jury is out on whether digital is superior.

On the occasion of Analog Device's 40th birthday on February 3, I asked Co-founder and Chairman Ray Stata to reflect on whether there was ever a time he thought the company would not survive.

"There was never a time when I thought we wouldn't make it, but we went through some dry spells in mid-'80s where there was a widespread recession. We had to go through some major transitions. There was turmoil and dissatisfaction in trying to make those changes. [These changes involved] centralizing manufacturing from a decentralized operation and upgrading our manufacturing to become world-class, which we weren't before. Those were challenging times from 1986 to '87 through '94. We had to go through enormous changes in the kind of company we were. I didn't doubt we could do it, but we were referred to as a 'once-great' company. That kind of hurt. Fortunately, we came out positively on the other side."

Speaking of changes, we have a few of our own. We've promoted Matt Miller to executive editor, online. Matt has already overseen major improvements to our Web site in design, usability, and content. For instance, we now post upward of a half-dozen new stories a day, including a biweekly news feed from EDN Japan. We've also hired Senior Editor Michael Santarini, who is based in our San Jose bureau, where he'll cover EDA, programmable logic, ASICs, and memory. He joins us from EE Times, where he spent seven years covering EDA. Finally, Jeff Berman has joined EDN as online news editor to write and solicit content for our Web site. All three would love to hear from you.

When isn't digital better? Write me at john.dodge@reedbusiness.com.