This is a simple switched capacitor filter made by National. Would
somebody send me a copy, or at least provide a URL that HAS it!!! and not
datasheet or alldata crap! If AppNote available that too please.

I just went through the most frustrating 45 minutes trying to get a simple
!@#$#@!#$ data sheet! Google search shows 8,000+ pages of either alldata,
or datasheet, ok so tried going to both, all I got there were ads for
unrelated chips and ?? couldn't even tell, kept asking me to download a
pdf viewer!! what?!

So thought I'd go to the source [which I usually do first] went to
http://www.national.com which of course took me to http://www.ti.com
because TI bought out National and TI's website is usually pretty easy to
navigate so did a search for LMF90 only to come up with nothing found.

I'd like a URL ending in .pdf so I can click on it and select 'download
the contents of the link', instead of going off to some jave infected
website that either hangs, delays, my system or wants to give me videos,
and no where in sight is a place to get a copy of the datasheet. Even the
'view' data sheet resulted in nothing happening!! arrrggg! ...temporary
end of rant.

So, anybody have a copy, or know a 'good' URL?

On Mon, 27 Jan 2014, RobertMacy wrote:

This is a simple switched capacitor filter made by National. Would somebody
send me a copy, or at least provide a URL that HAS it!!! and not datasheet or
alldata crap! If AppNote available that too please.

Have you got the part number right? National's first generation filter
like that had some other prefix (I can't remember what, I'd know the minute I
saw it). I'm thinking "MFC" but I don't know why. It didn't start
with National's traditional prefix, "LM". Maybe later they used some other
prefix, but I'd double check.

Michael

I just went through the most frustrating 45 minutes trying to get a simple
!@#$#@!#$ data sheet! Google search shows 8,000+ pages of either alldata, or
datasheet, ok so tried going to both, all I got there were ads for unrelated
chips and ?? couldn't even tell, kept asking me to download a pdf viewer!!
what?!

So thought I'd go to the source [which I usually do first] went to
http://www.national.com which of course took me to http://www.ti.com
because TI bought out National and TI's website is usually pretty easy to
navigate so did a search for LMF90 only to come up with nothing found.

I'd like a URL ending in .pdf so I can click on it and select 'download the
contents of the link', instead of going off to some jave infected website
that either hangs, delays, my system or wants to give me videos, and no where
in sight is a place to get a copy of the datasheet. Even the 'view' data
sheet resulted in nothing happening!! arrrggg! ...temporary end of rant.

So, anybody have a copy, or know a 'good' URL?

On 27.1.14 17:02, RobertMacy wrote:
This is a simple switched capacitor filter made by National. Would
somebody send me a copy, or at least provide a URL that HAS it!!! and
not datasheet or alldata crap! If AppNote available that too please.

I just went through the most frustrating 45 minutes trying to get a
simple !@#$#@!#$ data sheet! Google search shows 8,000+ pages of either
alldata, or datasheet, ok so tried going to both, all I got there were
ads for unrelated chips and ?? couldn't even tell, kept asking me to
download a pdf viewer!! what?!

So thought I'd go to the source [which I usually do first] went to
http://www.national.com which of course took me to http://www.ti.com
because TI bought out National and TI's website is usually pretty easy
to navigate so did a search for LMF90 only to come up with nothing found.

I'd like a URL ending in .pdf so I can click on it and select 'download
the contents of the link', instead of going off to some jave infected
website that either hangs, delays, my system or wants to give me videos,
and no where in sight is a place to get a copy of the datasheet. Even
the 'view' data sheet resulted in nothing happening!! arrrggg!
...temporary end of rant.

So, anybody have a copy, or know a 'good' URL?

Just got a copy from:
http://doc.chipfind.ru/nsc/lmf90.htm.

--

Tauno Voipio

On Mon, 27 Jan 2014 08:26:10 -0700, Tauno Voipio
wrote:

...snip...
Just got a copy from:
http://doc.chipfind.ru/nsc/lmf90.htm.


THANK YOU !!!!

At first I couldn't figure out the significance of the giant offer to
download a spec for a PIC, but below that was indeed a URL that yielded
the .pdf ending so I could download. Got it thanks

....now any AppNotes floating around?

On Mon, 27 Jan 2014 10:18:27 -0500, Michael Black wrote:

On Mon, 27 Jan 2014, RobertMacy wrote:

This is a simple switched capacitor filter made by National. Would somebody
send me a copy, or at least provide a URL that HAS it!!! and not datasheet or
alldata crap! If AppNote available that too please.

Have you got the part number right? National's first generation filter
like that had some other prefix (I can't remember what, I'd know the minute I
saw it). I'm thinking "MFC" but I don't know why. It didn't start
with National's traditional prefix, "LM". Maybe later they used some other
prefix, but I'd double check.

National's classic switched-cap filter was the MF10, metal-gate CMOS. There was
a later poly-gate version, can't remember the part number.

Overall, switched-cap filters weren't all that great. OK for some apps, but they
were really noisy, and aliased anything available, including power supply crud.

I once designed a double-conversion superhet FSK modem full of MF10s, for
Reuters' landline newswire service. Sold a few before PCs and the Internet made
the classic newswire thing obsolete.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On 01/27/2014 11:27 AM, John Larkin wrote:
On Mon, 27 Jan 2014 10:18:27 -0500, Michael Black wrote:

On Mon, 27 Jan 2014, RobertMacy wrote:

This is a simple switched capacitor filter made by National. Would somebody
send me a copy, or at least provide a URL that HAS it!!! and not datasheet or
alldata crap! If AppNote available that too please.

Have you got the part number right? National's first generation filter
like that had some other prefix (I can't remember what, I'd know the minute I
saw it). I'm thinking "MFC" but I don't know why. It didn't start
with National's traditional prefix, "LM". Maybe later they used some other
prefix, but I'd double check.

National's classic switched-cap filter was the MF10, metal-gate CMOS. There was
a later poly-gate version, can't remember the part number.


The LMF100. Nice part if you needed to do anything fancy and low SNR
was okay. I used it to make a SSB mixer once, and it worked great.

Overall, switched-cap filters weren't all that great. OK for some apps, but they
were really noisy, and aliased anything available, including power supply crud.

I once designed a double-conversion superhet FSK modem full of MF10s, for
Reuters' landline newswire service. Sold a few before PCs and the Internet made
the classic newswire thing obsolete.

The clock-tunable thing was pretty convenient for some jobs, especially
back when tight-tolerance capacitors were expensive.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

On Mon, 27 Jan 2014 11:30:37 -0500, Phil Hobbs
wrote:

On 01/27/2014 11:27 AM, John Larkin wrote:
On Mon, 27 Jan 2014 10:18:27 -0500, Michael Black wrote:

On Mon, 27 Jan 2014, RobertMacy wrote:

This is a simple switched capacitor filter made by National. Would somebody
send me a copy, or at least provide a URL that HAS it!!! and not datasheet or
alldata crap! If AppNote available that too please.

Have you got the part number right? National's first generation filter
like that had some other prefix (I can't remember what, I'd know the minute I
saw it). I'm thinking "MFC" but I don't know why. It didn't start
with National's traditional prefix, "LM". Maybe later they used some other
prefix, but I'd double check.

National's classic switched-cap filter was the MF10, metal-gate CMOS. There was
a later poly-gate version, can't remember the part number.


The LMF100. Nice part if you needed to do anything fancy and low SNR
was okay. I used it to make a SSB mixer once, and it worked great.

Overall, switched-cap filters weren't all that great. OK for some apps, but they
were really noisy, and aliased anything available, including power supply crud.

I once designed a double-conversion superhet FSK modem full of MF10s, for
Reuters' landline newswire service. Sold a few before PCs and the Internet made
the classic newswire thing obsolete.

The clock-tunable thing was pretty convenient for some jobs, especially
back when tight-tolerance capacitors were expensive.


Yeah, the modem did any channel, and any one of three baud rate/bandwidths, with
just dip switches. The older stuff had plug-in LC filters.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On 01/27/2014 10:02 AM, RobertMacy wrote:
This is a simple switched capacitor filter made by National. Would
somebody send me a copy, or at least provide a URL that HAS it!!! and
not datasheet or alldata crap! If AppNote available that too please.

I just went through the most frustrating 45 minutes trying to get a
simple !@#$#@!#$ data sheet! Google search shows 8,000+ pages of either
alldata, or datasheet, ok so tried going to both, all I got there were
ads for unrelated chips and ?? couldn't even tell, kept asking me to
download a pdf viewer!! what?!

So thought I'd go to the source [which I usually do first] went to
http://www.national.com which of course took me to http://www.ti.com
because TI bought out National and TI's website is usually pretty easy
to navigate so did a search for LMF90 only to come up with nothing found.

I'd like a URL ending in .pdf so I can click on it and select 'download
the contents of the link', instead of going off to some jave infected
website that either hangs, delays, my system or wants to give me videos,
and no where in sight is a place to get a copy of the datasheet. Even
the 'view' data sheet resulted in nothing happening!! arrrggg!
...temporary end of rant.

So, anybody have a copy, or know a 'good' URL?

The app note mentioning the LMF90 was AN779, but they edited it out of
AN 779A. The old version is at
http://www.swarthmore.edu/NatSci/ech...oToFilters.pdf

Cheers

Phil Hobbs



--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

On 01/27/2014 10:02 AM, RobertMacy wrote:
This is a simple switched capacitor filter made by National. Would
somebody send me a copy, or at least provide a URL that HAS it!!! and
not datasheet or alldata crap! If AppNote available that too please.

I just went through the most frustrating 45 minutes trying to get a
simple !@#$#@!#$ data sheet! Google search shows 8,000+ pages of either
alldata, or datasheet, ok so tried going to both, all I got there were
ads for unrelated chips and ?? couldn't even tell, kept asking me to
download a pdf viewer!! what?!

So thought I'd go to the source [which I usually do first] went to
http://www.national.com which of course took me to http://www.ti.com
because TI bought out National and TI's website is usually pretty easy
to navigate so did a search for LMF90 only to come up with nothing found.

I'd like a URL ending in .pdf so I can click on it and select 'download
the contents of the link', instead of going off to some jave infected
website that either hangs, delays, my system or wants to give me videos,
and no where in sight is a place to get a copy of the datasheet. Even
the 'view' data sheet resulted in nothing happening!! arrrggg!
...temporary end of rant.

So, anybody have a copy, or know a 'good' URL?

And there's a real datasheet at
http://www.datasheetarchive.com/dlma...DSA-424155.pdf

Since the parasites have taken over the search engine ecosystem,
Datasheetarchive's built-in search works better than using Google to
search DSA.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

On Mon, 27 Jan 2014, John Larkin wrote:

On Mon, 27 Jan 2014 10:18:27 -0500, Michael Black wrote:

On Mon, 27 Jan 2014, RobertMacy wrote:

This is a simple switched capacitor filter made by National. Would somebody
send me a copy, or at least provide a URL that HAS it!!! and not datasheet or
alldata crap! If AppNote available that too please.

Have you got the part number right? National's first generation filter
like that had some other prefix (I can't remember what, I'd know the minute I
saw it). I'm thinking "MFC" but I don't know why. It didn't start
with National's traditional prefix, "LM". Maybe later they used some other
prefix, but I'd double check.

National's classic switched-cap filter was the MF10, metal-gate CMOS. There was
a later poly-gate version, can't remember the part number.

Yes, that's what I was remembering.

Overall, switched-cap filters weren't all that great. OK for some apps, but they
were really noisy, and aliased anything available, including power supply crud.

It's one of those things that were transitory, like charge coupled delay
lines. Fill in a gap, relatively late, that soon could be done by
converting to digital and doing the work there.

Michael

I once designed a double-conversion superhet FSK modem full of MF10s, for
Reuters' landline newswire service. Sold a few before PCs and the Internet made
the classic newswire thing obsolete.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On Mon, 27 Jan 2014 09:39:12 -0700, John Larkin
wrote:

On Mon, 27 Jan 2014 11:30:37 -0500, Phil Hobbs
wrote:
...snip....
The clock-tunable thing was pretty convenient for some jobs, especially
back when tight-tolerance capacitors were expensive.


Yeah, the modem did any channel, and any one of three baud
rate/bandwidths, with
just dip switches. The older stuff had plug-in LC filters.



Actually, I only really needed the DataSheet and any AppNotes. but is ok,
got the data sheet and an AppNote.