Re: 555; was: Re: Who is your favourite electronics guru?

On Sat, 12 Aug 2006 18:30:49 -0400, "mc"
<look@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

<bill.sloman@xxxxxxxx> wrote in message
news:1155421641.296694.20070@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Not exactly. The absence of any modern competitior for the 555's slot
has more to say about the absence of any serious application for the
555 in mass-produced devices than it has to say about the quality of
the original design.

Interesting thought. I use 555s a lot developing one-of-a-kind prototypes.
But I'm inclined to agree that in a more complex, more systematically
designed system, there probably aren't going to be many 555-shaped holes, so
to speak. Switching and timing are done by the CPU if there is one.
Oscillators can be cobbled together out of leftover gates. And so on.

In one of my current projects I am deliberating between a 555 and an 8-pin
microcontroller. Given that we save a couple of diodes and capacitors, the
micro may be cheaper! And it opens up the possibility of adding other
intelligent behavior, response to additional sensors, soft start-up, status
indicators, etc., all by just writing more code.

The appeal of the 555 is that I can give a hobbyist a circuit that can be
built with Radio Shack parts, with no device programming.

---
Precisely.

Most requests on these groups don't ask for, "How can I program a
microcontroller to do this or that?" , they ask for a circuit which
can do what they want to be done and which can be built with glue
logic and discretes.


--
John Fields
Professional Circuit Designer
.

Relevant Pages

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