Re: How inaccurate is a 555 or 7555 REALLY?


Phil Allison wrote:
<bill.slowman@xxxxxxxx>

John Fields:

Still hanging on to that pig-ignorant belief that a 555 is a "bad"
chip which no one should use because you won't? Even when it's the
perfect candidate for the job?

It isn't a "bad" chip, but very rarely an acceptable candidate for any
job in serious electronics these days. There was a thread about this
here a while back, and the concensus was that most professional
electronic engineers don't seem to be using it any more.


** Funny how they sell over 1 billion examples each year then, isn't it
????

Not at all. Legacy designs, and land occasional egacy designer, like
John Fields, are an entirely sufficient explanation.

The 555 ( and variants) have been and continue to be BY FAR the world's
largest selling IC type ever since it appeared in 1972.

It would be interesting to see the shape of the buying curve - the
number bought per year every year since the part was introduced. I
suspect that that curve peaked a number of years ago, and part is now
selling predominantly into the continueing production of old designs.

You had maybe better read this:

http://semiconductormuseum.com/Transistors/LectureHall/Camenzind/Camenzind_Index.htm

I've got a copy of Camenzind's book, and I've not only read the chapter
on the 555, but I've also commented on it here - Camenzind can now see
how he might have done a better job on the original 555, not that this
would have made much difference to its usefulness or sales.

--
Bill Sloman, Nijmegen (but in Sydney at the moment)

.

Relevant Pages

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  • Re: How inaccurate is a 555 or 7555 REALLY?
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