[ppl]

The lineage of the Diamond Buffer can be traced to the Classic national semiconductor Line of Hybrid Buffers starting with the LH-0002. and continuing with an apparent never ending line of newer products. From the LH-0002 was introduced in 1968. From 1979 is AN-227 this denotes the applications of the LH-0002 and provides technical details of its operation.
http://www.national.com/an/AN/AN-227.pdf

The LH-0002 is discontinued as of about 1989 however the data sheet in its last reveison is located at this link
http://cache.national.com/ds/LH/LH0002.pdf

an fet input of this Buffer was also widely used for High Impedance sources this part was the LH-0033. data sheet is located at
http://cache.national.com/ds/LH/LH0033.pdf

Schematic and Design details for a slightly more complex Dimond Buffer is from Maxiam.
http://www.maxim-ic.com/appnotes.cfm...mber/378/ln/en

For the Technically Knowledgeable person this NASA Article denotes some of the calculations on application specific Design implementations
http://techreports.larc.nasa.gov/ltr...-95-tm4658.pdf

A definitive long time reference of mine regarding op amp and output booster stages from linear technology. This is a long 132 page pdf file However IMHO a Must read
Pages 45-47 show Discrete Dimond buffer circuits
http://www.linear.com/pdf/an47fa.pdf

There was some real interesting Articles on open loop buffers on Elantecs site However Intersill has completely merged Elantec’s site with interssill’s so these docs are unavailable anymore or at least I could not find them. However the above should keep you reading until the snow flies

 

[JohnFerrier]

PPL

Thanks for the interesting post (will browse through it all). I had printed out the long AN47 because of you mentioning it before. I like their dead bug circuitry. Might be using some of that myself. For N of 1, don't mind eliminating the FR4 (have teflon if necessary). Also, found your past posts on current sources and the multi-loop circuits interesting. Yep, my head is hurting. Hope to actually build something soon. So far I've only spent about $8 on an Audio Express magazine. (Spent a lot of time though.) Currently, have a lot of nice components just waiting to be put together. Just trying to absorb things now. I would have thought it would be easier. Oh, well, have to accept reality. Plan to build just one amplifier to last (say five years--then maybe revisit the situation). Hope to get it right the first time.

Take care.


JF

 

[Budgie]

Thanks ppl. Alot of stuff to absorb! I am not sure how much I will get, but what a great application note from Linear!

 

[tangent]

Just to complete the record, you can find discrete implementations of this idea by Walt Jung in _IC Op-Amp Applications_ (p.378) and in Electronic Design. The notable thing about these discrete circuits is the LED-biased current sources for the drive transistors. Naturally there are no LEDs in the original LH00xx buffers....

Beware of relying on elecdesign.com links. They keep redesigning their site, breaking links. Even as I write this, these links point to pages in their site that you can't get to through their archive or search engine -- you just have to know the URL. I suspect these pages are going to be moved or removed eventually, so save the files or print them out if you want to refer back to them later.

 

[ppl]

Thanks tangent forgot about Walt’s article and probably some others as well perhaps we could get a moderator make this a sticky thread and others can also post regarding Diamond buffers. However like all such threads posts should be on topic as like no single end and other non related topics.

Your welcome John as for your quest for Knowledge Remember, “A Journey of 1000 Miles begins with that first step”

 

[Voodoochile]

That's a lot to get through, but very interesting, PPL. I do plan to get through it.

Also, I like this type of post very much, as did I also like the "Brief History of the Didden/Jung Super Regulator" and it's sidebars and parallels that Tangent posted a short while back.

It would be nice to have a sticky thread or reference thread even, with some posts detailing of the historical development timelines of some of these popular circuits and/or topologies, with linkage throughout.

Does anybody else support this thought?

 

[Gariver]

ppl you really are a 1st class audio researcher. You manage to dig up lots of good stuff. Thanks!!!

 

[tbla]

Quote:

"Brief History of the Didden/Jung Super Regulator"

can't find it....where is it....?

 

[tangent]

Quote:

can't find it....where is it....?

There's a short history here on Head-Fi, but I went and expanded it greatly and put it on my web site. Here 'tis.

 

[tbla]

thanks alot....btw is it usefull/a must to expand the bandwidth on the buf634 - in a jung multiloop config - using a opa637 with gain 300.....?

 

[ppl]

Yes the Buf-634 states that the OPA-637 should be used in the Wide band mode. The OPA-637 will work in the Low bandwidth mode in a Multi-loop arangement however this will not give the best performance.

 

[tangent]

Useful, yes. Required, no.

It's just a question of how much current you're willing to trade for sound quality.

 

[ppl]

Quote:

Originally posted by Gariver ppl you really are a 1st class audio researcher. You manage to dig up lots of good stuff. Thanks!!!

Actualy i lived throught this history and thus Know where this info should be located at. Yes you can call me Old.

Voodochillie nice Max headroom Avitar

 

[tbla]

Quote:

The OPA-637 will work in the Low bandwidth mode in a Multi-loop arangement however this will not give the best performance.

by that you mean - even its not requiret, best sound is obtained when the buf634 is run in full bandwidth mode....?

 

[Voodoochile]

Quote:

Originally posted by ppl Actualy i lived throught this history and thus Know where this info should be located at. Yes you can call me Old. Voodochillie nice Max headroom Avitar

Okay, you're old.
I have to say that, as you are one of a handful that are older than me!

Glad you like my pic

, even that seems relatively old. I liked the show, though.