[Pease Porridge]
Bob's Mailbox
Bob Pease
ED Online ID #18589
April 24, 2008
Copyright © 2006 Penton Media, Inc., All rights reserved. Printing of this document is for personal use only.
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HELLO BOB,
A note concerning electric cars and plugin
hybrids: Consider that politics has little to
do with engineering and/or science. It only
pays lip service at those altars. So, somebody has to do serious
planning for the immediate future.
I’ve been working on some serious battery-charger designs.
One of our planners (an engineer) did some research in good
old California. We learned that your utility companies have
problems with metering even small numbers of plug-ins, nor
can the California infrastructure absorb many cells of even
5000 plug-ins. You’re running at about 81% capacity, and without
a smart meter and control, we would easily overload the
electricity capacity on two peaks every day. That’s not politics.
It’s business.
American, Japanese, and European manufacturers were
contacted, and none of us can really do this without the cooperation
of the utilities. Oh sure, we can sell a few and look
green. The press wouldn’t even know who to blame when the
grid broke. Some of our competitors have been doing that,
but without that smart meter, it’s the wrong thing to do. They
know it. But that’s business.
All of the automakers easily agreed on the meter and protocol.
The utilities did not. They already have contracts on meters
that aren’t smart. That’s business. The real greenies were there,
too. They’re part of politics. They want California to be energy
neutral in 10 years—sorry, no data on how to do it. Industry
must be hiding it.
Back in the Midwest, we run about 1/2 the total power per
person aggregate (at 740 W per person continuous) than you
do out west, but that’s because of our low transport and air
conditioning costs. Perhaps just targeting our levels would be
a better starting point. There is no magic bullet in the next 10
years. So the utilities answer to the greenies and business, not
to the engineers. Our charger is going to be great. We will get
patents. It will be used all over, but not in volume in the west.
–AN ANONYMOUS ENGINEER
HELLO, ANONYMOUS: I’ve always been suspicious of the “visionaries” who think
it is going to be so great to have lots of electric cars, plug-in
hybrids, and hydrogen-powered cars. Who is going to build
the electrical generating and power-transmission capacity for
recharging a lot of cars? Who is going to make the hydrogen
fueling stations and the hydrogen generators?
Not the same people who are smoking bad stuff and dreaming
improbable dreams. Thanks for reminding us. Right now,
the only thing saving us from these problems is the high cost
and limited availability of such cars. If we got more such cars,
we would not be able to drive them to work the next day after a
little heat wave.
–RAP
DEAR MR. PEASE, I’ve often used components in various packages: TO-92,
TO-220, and so on. Usually, these components are pulled off the
shelf without any thought to the package they are in apart from
obvious questions such as “Will the package handle the power
to be dissipated?” (Oh, I disagree! We engineers usually pick a
part in a (compact) package that makes some sense for the task at
hand. We don’t pick a 20-W package to do a 28-mW job, nor vice
versa. And if I ever tried to do that, when I was a kid engineer, my
boss would have chewed me out. So we all have to learn somewhere.
I mean, who ever went to school to learn about heatsinking?
/rap) I’ve been wondering, though, what the history of these
packages is. (It is obvious that each package is a compromise of
all those terms, so TO-92 (and its variant packages) will dissipate
almost a watt—just before the thing dies! /rap) Who designed
each one? (Probably 34 different JEDEC committees... /rap)
Why did they choose the particular shape it is? (Surely, because
the guys who said they could make it argued that it was a feasible
package to make in high volumes profitably... with good results
for the users. /rap) What were the tradeoffs that had to be made
during development? When did it first get used and why? (I
wasn’t there. How the hell would I know? /rap) There seems to be
absolutely no information on such things. I’m sure an awful lot of
R&D went into those packages, but it just seems to have disappeared,
leaving only the application information (such as package
drawings) behind.
–JOHN DALTON
HI, JOHN: On the contrary. The history has dried up, but the facts remain.
These packages remain as examples of packages that have been,
some of them, very popular—in the dozens of billions! Which
other packages have you considered? The TO-2, TO-4, TO-6?
TO-91? TO-93? Who the hell ever heard of them? Nobody!
And guess why? I doubt if there are many survivors of that era
who would like to talk about their struggles with these packages,
are there? But all of the packages that survived were subject to the
realm of feasibility.
-RAP
Comments invited! rap@galaxy.nsc.com —or:
Mail Stop D2597A, National Semiconductor
P.O. Box 58090, Santa Clara, CA 95052-8090
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