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Opamps - everything

Started by Unknown January 18, 2017
On Thu, 19 Jan 2017 13:54:47 -0800 (PST), tabbypurr@gmail.com wrote:

>On Wednesday, 18 January 2017 20:37:26 UTC, tabby wrote: >> Jim Thompson wrote >> >> >> > Math ?? If you're only a user, you can write down all you need to >> > know about OpAmps in a couple of pages. >> > >> > ...Jim Thompson > >I reckon you were right. Just *** big pages :) > > >NT
Yep. I wrongly supposed that the readers here didn't need help with applications >:-} ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | STV, Queen Creek, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I'm looking for work... see my website. Thinking outside the box... producing elegant solutions.
On Thursday, 19 January 2017 22:49:54 UTC, Jim Thompson  wrote:
> On Thu, 19 Jan 2017 13:54:47 -0800 (PST), tabbypurr wrote: > >On Wednesday, 18 January 2017 20:37:26 UTC, tabby wrote: > >> Jim Thompson wrote > >> > >> > >> > Math ?? If you're only a user, you can write down all you need to > >> > know about OpAmps in a couple of pages. > >> > > >> > ...Jim Thompson > > > >I reckon you were right. Just *** big pages :) > > > > > >NT > > Yep. I wrongly supposed that the readers here didn't need help with > applications >:-} > > ...Jim Thompson
Yeah, it's more for complete beginners. NT
On 18/01/2017 20:37, tabbypurr@gmail.com wrote:
> Jim Thompson wrote > > >> Math ?? If you're only a user, you can write down all you need to >> know about OpAmps in a couple of pages. >> >> ...Jim Thompson > > I'd be very interested in that. So lets see what would need to be covered: > > The basic idea of what an opamp is and how closing the loop enables it to do all sorts. > Understanding the specs
TI have quite a nice paper by Jim Karki on the differences between the idealised mathematicians perfect OPAMP and their engineering reality. http://www.ti.com/lit/an/sloa011/sloa011.pdf -- Regards, Martin Brown
On Fri, 20 Jan 2017 08:40:46 +0000, Martin Brown
<|||newspam|||@nezumi.demon.co.uk> wrote:

>On 18/01/2017 20:37, tabbypurr@gmail.com wrote: >> Jim Thompson wrote >> >> >>> Math ?? If you're only a user, you can write down all you need to >>> know about OpAmps in a couple of pages. >>> >>> ...Jim Thompson >> >> I'd be very interested in that. So lets see what would need to be covered: >> >> The basic idea of what an opamp is and how closing the loop enables it to do all sorts. >> Understanding the specs > >TI have quite a nice paper by Jim Karki on the differences between the >idealised mathematicians perfect OPAMP and their engineering reality. > >http://www.ti.com/lit/an/sloa011/sloa011.pdf
The 'e' component in LT Spice is almost an ideal opamp. -- John Larkin Highland Technology, Inc lunatic fringe electronics
On Fri, 20 Jan 2017 07:14:46 -0800, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

>On Fri, 20 Jan 2017 08:40:46 +0000, Martin Brown ><|||newspam|||@nezumi.demon.co.uk> wrote: > >>On 18/01/2017 20:37, tabbypurr@gmail.com wrote: >>> Jim Thompson wrote >>> >>> >>>> Math ?? If you're only a user, you can write down all you need to >>>> know about OpAmps in a couple of pages. >>>> >>>> ...Jim Thompson >>> >>> I'd be very interested in that. So lets see what would need to be covered: >>> >>> The basic idea of what an opamp is and how closing the loop enables it to do all sorts. >>> Understanding the specs >> >>TI have quite a nice paper by Jim Karki on the differences between the >>idealised mathematicians perfect OPAMP and their engineering reality. >> >>http://www.ti.com/lit/an/sloa011/sloa011.pdf > >The 'e' component in LT Spice is almost an ideal opamp.
The 'E' component is in _all_ Berkeley-compliant Spice variants. 'E' alone gives fake results because it has no roll-off, or, almost more importantly, doesn't have a 90&#2013266096; phase shift. "Op-Amp-Config.zip" on the Device Models & Subcircuits page of my website presents a fair representation of real OpAmps... and is configurable by the user by simply inputting datasheet information. It is several generations old... I have newer versions that are quite accurate, but require a "spreadsheet" to obtain the coefficients of the model. I do not share the spreadsheet. only the application-specific subcircuit >:-} ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | STV, Queen Creek, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I'm looking for work... see my website. Thinking outside the box... producing elegant solutions.
On Fri, 20 Jan 2017 08:28:36 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

>On Fri, 20 Jan 2017 07:14:46 -0800, John Larkin ><jjlarkin@highlandtechnology.com> wrote: > >>On Fri, 20 Jan 2017 08:40:46 +0000, Martin Brown >><|||newspam|||@nezumi.demon.co.uk> wrote: >> >>>On 18/01/2017 20:37, tabbypurr@gmail.com wrote: >>>> Jim Thompson wrote >>>> >>>> >>>>> Math ?? If you're only a user, you can write down all you need to >>>>> know about OpAmps in a couple of pages. >>>>> >>>>> ...Jim Thompson >>>> >>>> I'd be very interested in that. So lets see what would need to be covered: >>>> >>>> The basic idea of what an opamp is and how closing the loop enables it to do all sorts. >>>> Understanding the specs >>> >>>TI have quite a nice paper by Jim Karki on the differences between the >>>idealised mathematicians perfect OPAMP and their engineering reality. >>> >>>http://www.ti.com/lit/an/sloa011/sloa011.pdf >> >>The 'e' component in LT Spice is almost an ideal opamp. > >The 'E' component is in _all_ Berkeley-compliant Spice variants. 'E' >alone gives fake results because it has no roll-off, or, almost more >importantly, doesn't have a 90&#2013266096; phase shift.
It works fine for DC analysis. If you want a rolloff, add an RC at the output. Its advantage over UniversalOpamp2 is that it doesn't need power supplies. There used to be a UniversalOpamp that didn't need supplies, I think, but it's gone. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com