Replacement for 741

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t".

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d the board in 1976.

n, NE5532.

'Precision',

============

Huh, I didn't know that. I used plenty with no problems... just lucky I gu ess. :^)

George H. I sometimes hang a cap on the output to slow the transition.

As long as no input went below ground, and no opamp section railed, they were sort of OK. Barbaric by modern standards, as is the 741.

A few old parts have held up. LM317/1117 for example.

Look at all the cool stuff you get for 25 cents per in quantities of

500, programmed by the manufacturer:

Somebody would have to program it, and release all the files, and make a deal with a distributor to program it. Hassle, compared to a few analog parts on a schematic.

We have one ARM chip programmed for us by a distributor, because we buy a lot of them for a fairly expensive product. The function is too complex to do without a uP.

Yeah, todays opamps 'blow the doors off' any older stuff. I don't know comparators as well... oh there was an LT part.. LT1016, I think. That's a nice snappy comparator. (not cheap)

Oh to the OP as far as parts not in DIP's. Your best best is to buy some of these little pcb's that do soic to dip. A buck or so each on Digikey I think.

George H.

A quick search showed alot of LT1016(s) in DIP packages ? Is that old product ?

The original LM324 had one shared bias generator, with a mirror transistor per section. If you went below VEE, you saturated your mirror output, which promptly ate all the base drive for the other sections' mirrors.

They fixed that pretty promptly iirc--does anybody know if the 393 does it?

Cheers

Phil Hobbs

The LT1016 is a fast (in my world) comparator. We used it to measure/ count time differences between optical pulses. It's speedy and stable with respect to the transistion voltage. You pay for all that. (and you sometimes don't want the fast edge.) It sounded more like you wanted cheaper and slower. lm393... buy 10, probably cheaper than one lt1016 buy 25 for ~$8

GH

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nt".

ut

ped the board in 1976.

ion, NE5532.

vs 'Precision',

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guess. :^)

t?

All I can say about the lm393, is that I have nothing bad to say about it. George H.

Yeah, I've used a lot of them too, mostly for current limiters, window comparators for PLL lock detection, overtemperature cutouts, interlocks, that sort of stuff. Anyplace that speed doesn't matter much and you can stand the input bias current. The lateral PNPs on the input will stand >+30V even when working from a 5V supply, which is handy. (No, it won't do any comparing if both inputs are outside the CM range.)

TLV7031/7041 are good if you need high-Z inputs or are very power-sensitive, but are 7V abs max.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
http://hobbs-eo.com

:

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ment".

hout

wiped the board in 1976.

rsion, NE5532.

l' vs 'Precision',

==============

I guess. :^)

s it?

it.

Current limiters? Oh, Series R in current path with 393 across the R. I'll vote the lm393 my jelly bean comparator. I don't think I have a jelly bean opamp. lm324 is the 'classic' choice, but I've never used one. lt1013 is all I've got... but too spendy for a jelly bean.

George H.

Or just measuring the programming voltage for a BJT current source. That's usually for protecting TECs. (393s are way too slow for protecting diode lasers.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
http://hobbs-eo.com

if you're looking for a 741 substitute used as a comparator how bot an lm311?

:

.

It is remarkably slow. But then again I think that the LT1016 is a bit slow . I got addicted to the AM685 early on, and it's variants have got quite a bit faster over the years (and even more prone to oscillate if you aren't v ery careful about layout, shielding and decoupling).

--
Bill Sloman, Sydney

The LM324, CA3140 and TL082, the Holy Trinity, blessed be these Cold War-era survivors.

Mouser has almost 50,000 of the SMT package available, a huge quantity, not many other op amps have stock numbers like that for one device type in one package.

te:

it.

ow. I got addicted to the AM685 early on, and it's variants have got quite a bit faster over the years (and even more prone to oscillate if you aren't very careful about layout, shielding and decoupling).

Slow is good for some applications. I've hung some C on the output of the

393 to slow it down even more. I never found any squirrelly behavior with the lt1016, it was easy to use in that way.

George H.

:

rote:

t it.

slow. I got addicted to the AM685 early on, and it's variants have got quit e a bit faster over the years (and even more prone to oscillate if you aren 't very careful about layout, shielding and decoupling).

393 to slow it down even more. I never found any squirrelly behavior with the lt1016, it was easy to use in that way.

It is a very nice part.

I once had to crawl over a board that used a lot of LM311 comparators. Fina l test hated the board because most the examples they got needed tweaking t o stop them oscillating.

I cleaned up the layout as much as I could, and made final test happier - s ome boards still oscillated, but it was easier to tweak them so that they d idn't.

The next machine used digital logic to do the job that had been done by the comparators, and didn't give any trouble at all, or at least not in that w ay.

--
Bill Sloman, Sydney

I recall that 741s had huge popcorn noise, but that may have been a process problem, not something inherent to the architecture.

--

John Larkin      Highland Technology, Inc 

The best designs are necessarily accidental.