?? TL084 = MC34084 ??
RST Engineering (jw)
Reading the data sheets, it seems that they are (at least to a good first
approximation) equivalents.
Is there a good reason why I can't put them in the same parts bin?
Jim
--
"It is the mark of an educated mind to be able to entertain a thought
without accepting it."
--Aristotle
Phil Hobbs
> I know that they are pin for pin, and I know that they are both opamps.
> Reading the data sheets, it seems that they are (at least to a good first
> approximation) equivalents.
>
> Is there a good reason why I can't put them in the same parts bin?
>
> Jim
>
<dim memory> ISTR that MC34084s have higher input capacitance and a much
wider output swing than the TL084.
</dim memory>
Cheers,
Phil Hobbs
Winfield Hill
> I know that they are pin for pin, and I know that they are both opamps.
> Reading the data sheets, it seems that they are (at least to a good first
> approximation) equivalents.
>
> Is there a good reason why I can't put them in the same parts bin?
Well, seeing that ON Semi discontinued all their JFET opamps
some time ago, you could just relabel that drawer for TI's part.
Jim Thompson
<j...@rstengineering.com> wrote:
>I know that they are pin for pin, and I know that they are both opamps.
>Reading the data sheets, it seems that they are (at least to a good first
>approximation) equivalents.
>
>Is there a good reason why I can't put them in the same parts bin?
>
>Jim
When I used them extensively in the early '80's I did presume
"sameness".
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine Sometimes I even put it in the food
Rich Grise
> I know that they are pin for pin, and I know that they are both opamps.
> Reading the data sheets, it seems that they are (at least to a good first
> approximation) equivalents.
>
> Is there a good reason why I can't put them in the same parts bin?
>
Yes - they have different part numbers. ;-)
Have Fun!
Rich
Tim Shoppa
<j...@rstengineering.com> wrote:
> I know that they are pin for pin, and I know that they are both opamps.
> Reading the data sheets, it seems that they are (at least to a good first
> approximation) equivalents.
>
> Is there a good reason why I can't put them in the same parts bin?
>
> Jim
I often see the MC34084 used in industrial control circuitry where the
power supply rails are +/-20 or +/-22 V.
The TL084 is I think only rated up to +/-18V.
There is a motorola chip like the LM358 that handles the bigger power
supply voltages too.
Tim.
Phil Hobbs
Phil Allison
"RST Engineering (jw)"
>I know that they are pin for pin, and I know that they are both opamps.
>Reading the data sheets, it seems that they are (at least to a good first
>approximation) equivalents.
** The MC part has several times more BW, SR and input voltage noise.
> Is there a good reason why I can't put them in the same parts bin?
** They are not equivalents.
What YOU put in YOUR bins is a private matter.
.... Phil
Eeyore
"RST Engineering (jw)" wrote:
> I know that they are pin for pin, and I know that they are both opamps.
> Reading the data sheets, it seems that they are (at least to a good first
> approximation) equivalents.
>
> Is there a good reason why I can't put them in the same parts bin?
Yes. The Motorola part is CRAP.
Stick with TI and the second sources of TL084s.
Graham
Eeyore
Jim Thompson wrote:
> On Mon, 19 Jan 2009 09:34:56 -0800, "RST Engineering \(jw\)"
> <j...@rstengineering.com> wrote:
>
> >I know that they are pin for pin, and I know that they are both opamps.
> >Reading the data sheets, it seems that they are (at least to a good first
> >approximation) equivalents.
> >
> >Is there a good reason why I can't put them in the same parts bin?
>
> When I used them extensively in the early '80's I did presume
> "sameness".
So you're not as smart as you claim. Crappiest op-amps I've ever had the
misfortune to come across. Oscillate if you look at them the wrong way.
Graham
RST Engineering (jw)
>> Well, seeing that ON Semi discontinued all their JFET opamps
>> some time ago, you could just relabel that drawer for TI's part.
>
Why would I do that? The drawer (bin, actually) is labeled 1-7114-0084; the
only thing I'd have to do is add the TL084 and the various folks who make it
to the approved vendor list for that part number.
Jim
Phil Hobbs
That was on account of the high input capacitance. With lower impedance
feedback, it worked fine. I especially liked the very wide output swing
and good slew rate. I even used the decompensated model, the MC34085.
Cheers,
Phil Hobbs
Eeyore
Phil Hobbs wrote:
> Eeyore wrote:
> > Jim Thompson wrote:
> >> "RST Engineering \(jw\)" <j...@rstengineering.com> wrote:
> >>
> >>> I know that they are pin for pin, and I know that they are both opamps.
> >>> Reading the data sheets, it seems that they are (at least to a good first
> >>> approximation) equivalents.
> >>>
> >>> Is there a good reason why I can't put them in the same parts bin?
> >> When I used them extensively in the early '80's I did presume
> >> "sameness".
> >
> > So you're not as smart as you claim. Crappiest op-amps I've ever had the
> > misfortune to come across. Oscillate if you look at them the wrong way.
>
> That was on account of the high input capacitance. With lower impedance
> feedback, it worked fine. I especially liked the very wide output swing
> and good slew rate. I even used the decompensated model, the MC34085.
So, NOT compatible then.
Graham
Phil Allison
"Phil Hobbles" :
> I especially liked the very wide output swing ...
** Get real.
It swings maybe 0.5 volts closer to the DC rails.
.... Phil
Winfield Hill
??? All I see is the mc34074, etc. all bipolar parts.
Jim Thompson
<pcdhSpamM...@electrooptical.net> wrote:
>Eeyore wrote:
>>
>> Jim Thompson wrote:
>>
>>> On Mon, 19 Jan 2009 09:34:56 -0800, "RST Engineering \(jw\)"
>>> <j...@rstengineering.com> wrote:
>>>
>>>> I know that they are pin for pin, and I know that they are both opamps.
>>>> Reading the data sheets, it seems that they are (at least to a good first
>>>> approximation) equivalents.
>>>>
>>>> Is there a good reason why I can't put them in the same parts bin?
>>> When I used them extensively in the early '80's I did presume
>>> "sameness".
>>
>> So you're not as smart as you claim. Crappiest op-amps I've ever had the
>> misfortune to come across. Oscillate if you look at them the wrong way.
>>
>> Graham
Replying to the jerk I normally plonk... what did YOU do wrong? Never
had a bit of trouble with that series of OpAmps... used them in
multiple high-production-run GenRad stuff... used more of them than
even TL430's ;-)
>>
>
>That was on account of the high input capacitance. With lower impedance
>feedback, it worked fine. I especially liked the very wide output swing
>and good slew rate. I even used the decompensated model, the MC34085.
>
>Cheers,
>
>Phil Hobbs
...Jim Thompson
Phil Hobbs
Cheers,
Phil Hobbs
Phil Hobbs
Not compatible with folks who design circuits without reading the data
sheets, or can't figure out how to calculate gain peaking due to input
capacitance, no.
Cheers,
Phil Hobbs
Phil Hobbs
I thought it was a nice feature, back in 1987 or so. What do you like?
Cheers,
Phil Hobbs
Jim Thompson
Phil Allison doesn't like much of anything... must have a constant bad
case of acid reflux... combined with diarrhea ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Labor Unions Cause Global Warming
Raveninghorde
I use the MC33172 as an HV LM358, often in versions of the same board
running from different supplies. Interchangeable in my apps.
Rich Grise
The way I learned it, suitable subs are OK, as long as they don't change
form, fit, or function.
Yes, I know I said, "Because they have different part numbers", but if you
have house numbers, you can put anything you want to in the bin, as long
as the customers are happy. :-)
Cheers!
Rich
Eeyore
Phil Hobbs wrote:
> Eeyore wrote:
> > Phil Hobbs wrote:
> >> Eeyore wrote:
> >>> Jim Thompson wrote:
> >>>> "RST Engineering \(jw\)" <j...@rstengineering.com> wrote:
> >>>>
> >>>>> I know that they are pin for pin, and I know that they are both opamps.
> >>>>> Reading the data sheets, it seems that they are (at least to a good first
> >>>>> approximation) equivalents.
> >>>>>
> >>>>> Is there a good reason why I can't put them in the same parts bin?
> >>>> When I used them extensively in the early '80's I did presume
> >>>> "sameness".
> >>> So you're not as smart as you claim. Crappiest op-amps I've ever had the
> >>> misfortune to come across. Oscillate if you look at them the wrong way.
> >> That was on account of the high input capacitance. With lower impedance
> >> feedback, it worked fine. I especially liked the very wide output swing
> >> and good slew rate. I even used the decompensated model, the MC34085.
> >
> > So, NOT compatible then.
>
> Not compatible with folks who design circuits without reading the data
> sheets, or can't figure out how to calculate gain peaking due to input
> capacitance, no.
I.e. NOT COMPATIBLE as in a plug-in replacement.
Graham
Eeyore
Jim Thompson wrote:
> Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:
> >Eeyore wrote:
> >> Jim Thompson wrote:
> >>> "RST Engineering \(jw\)" <j...@rstengineering.com> wrote:
> >>>
> >>>> I know that they are pin for pin, and I know that they are both opamps.
> >>>> Reading the data sheets, it seems that they are (at least to a good first
> >>>> approximation) equivalents.
> >>>>
> >>>> Is there a good reason why I can't put them in the same parts bin?
> >>> When I used them extensively in the early '80's I did presume
> >>> "sameness".
> >>
> >> So you're not as smart as you claim. Crappiest op-amps I've ever had the
> >> misfortune to come across. Oscillate if you look at them the wrong way.
>
> Replying to the jerk I normally plonk... what did YOU do wrong? Never
> had a bit of trouble with that series of OpAmps... used them in
> multiple high-production-run GenRad stuff... used more of them than
> even TL430's ;-)
Motorola promoted them here as plug in replacements for the TI bifets. They were
no such thing. We had better things to do than redesign everything to accept an
op-amp series that EVERY British audio company to my knowledge gave the cold
shoulder.
Motorola should have got the design right. Plenty of other companies made
compatible bifets over the years, notably National at the time.
Graham
Phil Hobbs
Of course, Motorola wasn't allowed to make a different part for
different applications...because you ran out of room in your brain. Of
course, the world obviously does revolve around you, so that's only to
be expected. The rest of us actually like having the choice of
different amps for different jobs.
Cheers,
Phil Hobbs
Eeyore
Phil Hobbs wrote:
> Of course, Motorola wasn't allowed to make a different part for
> different applications...because you ran out of room in your brain. Of
> course, the world obviously does revolve around you, so that's only to
> be expected. The rest of us actually like having the choice of
> different amps for different jobs.
How MORONIC are you ?
They were crap. So they didn't get used.
Graham
Phil Hobbs
>
> Phil Hobbs wrote:
>
>> Of course, Motorola wasn't allowed to make a different part for
>> different applications...because you ran out of room in your brain. Of
>> course, the world obviously does revolve around you, so that's only to
>> be expected. The rest of us actually like having the choice of
>> different amps for different jobs.
>
> How MORONIC are you ?
I don't know, Graham...it's not the sort of thing that it's possible to
know about oneself, is it? But don't hold back now...how moronic am I,
and how would you know?
>
> They were crap. So they didn't get used.
Not by you, anyway. I used them lots of places.
Cheers,
Phil Hobbs
Eeyore
Phil Hobbs wrote:
You obviously don't work in pro or high-end audio then. 0.02% THD !
Bwahahahahahahaa
Graham
Phil Hobbs
What was your first clue, Inspector?
0.02% THD !
> Bwahahahahahahaa
You're channelling Thompson, man! Snap out of it!
Cheers,
Phil Hobbs
krw
Thompson does disco balls?
Michael A. Terrell
Yes, but he uses a double barrel shotgun to 'fix' them.
--
http://improve-usenet.org/index.html
aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.
If you have broadband, your ISP may have a NNTP news server included in
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There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
Eeyore
krw wrote:
You never know. He might be a raver at heart ! Remember those pics with the belly
dancer ?
Graham
Jim Thompson
I actually designed and installed a boom box with synthesized sub-bass
into the Bobby McGee's on I17 at Northern, in the late '70's.
Reminds me... I promised to send a copy of the schematic to a friend
who is building his own house with a "theater room".
krw
One only wishes he "fixed" donkeys the same way.
Michael A. Terrell
krw wrote:
>
> Michael A. Terrell wrote:
> >
> >krw wrote:
> >>
> >> Thompson does disco balls?
> >
> >
> > Yes, but he uses a double barrel shotgun to 'fix' them.
>
> One only wishes he "fixed" donkeys the same way.
You can't fix a donkey. All you can do is turn them into dog food,
or boil them down into cheap glue.
krw
<mike.t...@earthlink.net> wrote:
>
>krw wrote:
>>
>> Michael A. Terrell wrote:
>> >
>> >krw wrote:
>> >>
>> >> Thompson does disco balls?
>> >
>> >
>> > Yes, but he uses a double barrel shotgun to 'fix' them.
>>
>> One only wishes he "fixed" donkeys the same way.
>
>
> You can't fix a donkey.
Certainly you can, preferably with a dull, rusty, knife.
> All you can do is turn them into dog food,
Why do you hate dogs so?
>or boil them down into cheap glue.
That's a *lot* of ugly glue!
Michael A. Terrell
krw wrote:
>
> On Thu, 05 Feb 2009 14:20:07 -0500, "Michael A. Terrell"
> <mike.t...@earthlink.net> wrote:
>
> >
> >krw wrote:
> >>
> >> Michael A. Terrell wrote:
> >> >
> >> >krw wrote:
> >> >>
> >> >> Thompson does disco balls?
> >> >
> >> >
> >> > Yes, but he uses a double barrel shotgun to 'fix' them.
> >>
> >> One only wishes he "fixed" donkeys the same way.
> >
> >
> > You can't fix a donkey.
>
> Certainly you can, preferably with a dull, rusty, knife.
A chain saw is better, and gets them ready for recycling.
> > All you can do is turn them into dog food,
>
> Why do you hate dogs so?
I only hate snarling, toothless European dogs.
>
> >or boil them down into cheap glue.
>
> That's a *lot* of ugly glue!
What do you think they use to repair ugly sticks?