Is there a standard comparator?

[Michael]

Hi - I was just wondering - is there a "classic" comparator? Like one that
is the standard comparator used in the majority of circuits that require
comparators? Thanks alot,

Michael

 

[Jim Thompson]

Hi - I was just wondering - is there a "classic" comparator? Like one that
is the standard comparator used in the majority of circuits that require
comparators? Thanks alot,

Michael

LM339

...Jim Thompson

 

[CFoley1064]

Hi - I was just wondering - is there a "classic" comparator? Like one that

is the standard comparator used in the majority of circuits that require
comparators? Thanks alot,

Michael

Hi again, Mike.

Single comparator -- LM311
Dual (2 per IC) -- LM393
Quad (4 per IC) -- LM339

Mike, you seem to be an intelligent guy. You sound like you're ready to take a
class in electronics, or at least get a couple of books from the library, and
look 'em over. Possibly you might want to grab a couple of data books, too.
For beginnners, I'd recommend the CMOS Cookbbook and TTL Cookbook by Don
Lancaster, as well as the National Semiconductor Linear Applications Handbook.
Another choice would be anything by Forrest Mims, who used to write for Popular
Electronics, and has written a number of things for RS and other magazines.
Look at a good basic high school/junior college electronics textbook, almost
every library has several.
Two good choices which might be (at least initially) a little over your head
for your library are the ARRL Handbook (try getting an earlier edition used --
they're commonly available at garage sales) and, of course, The Art of
Electronics. If you're only getting books where you know everything in them
already, you're wasting your time. I'm sure many other correspondents would
have many other ideas on how to start with gaining a systematic knowledge of
electronics, which it seems you're looking for and need. You won't find that
on a newsgroup, and there's always the old saw about going to the well too many
times.

Don't take this as a flame. Electronics is actually a branch of Engineering,
which is a discipline that requires systematic study to uinderstand. A
newsgroup isn't the place to do that. And by the way, basic questions should
be addressed to sci.electronics.basics and sci.electronics.components rather
than s.e.d.

I wish you luck, Mike. You seem like you're ready to step up to really
studying this field systematically.

Chris

 

[Michael]

[email protected] (CFoley1064) wrote in

Hi again, Mike.

Single comparator -- LM311
Dual (2 per IC) -- LM393
Quad (4 per IC) -- LM339

Mike, you seem to be an intelligent guy. You sound like you're ready
to take a class in electronics, or at least get a couple of books from
the library, and look 'em over. Possibly you might want to grab a
couple of data books, too. For beginnners, I'd recommend the CMOS
Cookbbook and TTL Cookbook by Don Lancaster, as well as the National
Semiconductor Linear Applications Handbook. Another choice would be
anything by Forrest Mims, who used to write for Popular Electronics,
and has written a number of things for RS and other magazines. Look at
a good basic high school/junior college electronics textbook, almost
every library has several.
Two good choices which might be (at least initially) a little over
your head for your library are the ARRL Handbook (try getting an
earlier edition used -- they're commonly available at garage sales)
and, of course, The Art of Electronics. If you're only getting books
where you know everything in them already, you're wasting your time.
I'm sure many other correspondents would have many other ideas on how
to start with gaining a systematic knowledge of electronics, which it
seems you're looking for and need. You won't find that on a
newsgroup, and there's always the old saw about going to the well too
many times.

Don't take this as a flame. Electronics is actually a branch of
Engineering, which is a discipline that requires systematic study to
uinderstand. A newsgroup isn't the place to do that. And by the way,
basic questions should be addressed to sci.electronics.basics and
sci.electronics.components rather than s.e.d.

I wish you luck, Mike. You seem like you're ready to step up to
really studying this field systematically.

Chris

So those three comparators are pretty much identical except for there
being different numbers of comparators in the package?


I've been slowly learning about electronics for a couple years now. I
pretty much go step by step - I get a component - play around with it
for a while. That's why I'm asking what the most common comparator is -
it's my next component to mess around with Or actually more I find
some random most likely pointless project to work on - and then figure
out how to do it. And the comparator fit the bill for my upcoming one

But don't worry - give me a couple years. I'm currently a freshmen in
electrical engineering at the university of illinois at urbana
champaign. I hope my posts will sounds a lot more educated soon I'm
taking my first intro to ECE class this spring (though I looked over the
sylabus - and it's pretty much just going to be review).

About SEB and SEC - I try posting in those newsgroups - but no one ever
replies. Those groups are all but dead.

Anyways thanks for your, and everyone else's, help. Sorry if I'm
bringing down the level of this newsgroup - but I really don't feel that
it's that big of a deal when people are spamming this newsgroup, posting
about completely off topic things, or just flaming for no apparent
reason.


Michael

 

[The Real Andy]

Anyways thanks for your, and everyone else's, help. Sorry if I'm
bringing down the level of this newsgroup - but I really don't feel that

It doesn't bring it down, it adds some flavour.

it's that big of a deal when people are spamming this newsgroup, posting
about completely off topic things, or just flaming for no apparent
reason.

Flaming and off topic post are pretty typical for engineering newsgroups.

 

[CFoley1064]

So those three comparators are pretty much identical except for there

being different numbers of comparators in the package?


I've been slowly learning about electronics for a couple years now. I
pretty much go step by step - I get a component - play around with it
for a while. That's why I'm asking what the most common comparator is -
it's my next component to mess around with Or actually more I find
some random most likely pointless project to work on - and then figure
out how to do it. And the comparator fit the bill for my upcoming one

But don't worry - give me a couple years. I'm currently a freshmen in
electrical engineering at the university of illinois at urbana
champaign. I hope my posts will sounds a lot more educated soon I'm
taking my first intro to ECE class this spring (though I looked over the
sylabus - and it's pretty much just going to be review).

About SEB and SEC - I try posting in those newsgroups - but no one ever
replies. Those groups are all but dead.

Anyways thanks for your, and everyone else's, help. Sorry if I'm
bringing down the level of this newsgroup - but I really don't feel that
it's that big of a deal when people are spamming this newsgroup, posting
about completely off topic things, or just flaming for no apparent
reason.


Michael

The datasheets for the three are available at the National Semiconductor
website.

You may want to look at the thread "Electronics Books?" which was posted
yesterday. There's a number of other _very_ good reference books listed there,
all of which will be available at your library.

 

[Stefan Heinzmann]

[email protected] (CFoley1064) wrote in

Single comparator -- LM311
Dual (2 per IC) -- LM393
Quad (4 per IC) -- LM339

[...]
So those three comparators are pretty much identical except for there
being different numbers of comparators in the package?

LM393 and LM339 are the same, LM311 is faster.

It would be a good exercise to study the datasheets of the parts so you
can see for yourself where the differences are. Comparators are
typically chosen because of
o speed
o supply voltage range
o common mode input voltage range
o precision (i.e. offset voltage)
o output circuit (open collector or totem pole)
and more...

As the above ICs are standard parts, they're available from many
manufacturers. The original is from National (www.national.com), they
still manufacture the parts. They've got a few more comparators, too, so
you can see where they differ. And check out the application notes.

Cheers
Stefan

 

[John Fields]

Anyways thanks for your, and everyone else's, help. Sorry if I'm
bringing down the level of this newsgroup - but I really don't feel that
it's that big of a deal when people are spamming this newsgroup, posting
about completely off topic things, or just flaming for no apparent
reason.

---
Yes, your questions are perfectly welcome here, and on topic as far as
I'm concerned. A large number of us here do electronics design for a
living and pretty much know what the most commonly used "standard" parts
are since we use them every day. No guarantees on seb, although a lot
of us hang out there, too.

The LM311 is completely different from the LM339/LM393 comparators and
you can get the data sheets for all three at National's site:

http://www.national.com/

 

[Michael]

It doesn't bring it down, it adds some flavour.


Flaming and off topic post are pretty typical for engineering newsgroups.

Really? I would expect engineers to be more professional than that - as
most any engineering field, especially electrical engineering, is a white
collar profession. I'll just blame it on the hobbyists

 

[Paul Burke]

Single comparator -- LM311
Dual (2 per IC) -- LM393
Quad (4 per IC) -- LM339

[...]

So those three comparators are pretty much identical except for there
being different numbers of comparators in the package?

LM393 and LM339 are the same, LM311 is faster.

It would be a good exercise to study the datasheets of the parts so you
can see for yourself where the differences are. Comparators are
typically chosen because of
o speed
o supply voltage range
o common mode input voltage range
o precision (i.e. offset voltage)
o output circuit (open collector or totem pole)
and more...

As the above ICs are standard parts, they're available from many

And don't ask for more speed than you really need. I got caught out this
way once, I wanted a little more speed than a 339 in a quad package, and
active pullups and built-in hysteresis looked attractive too. I went for
the frighteningly fast MAX944s. I could never stop them chattering. And
they don't have the standard comparator pinout (they are like opamps) so
yet another prototype iteration was needed.

Paul Burke