/Haps A New Basic Opamp App: The Floating Interactive Current Multiplier.

kokoriantz · 24th November 2020, 12:08 PM

This two resistor opamp circuit multiplies the input current by ( Rin/Rout+1).
The source sees the load impedance multiplied by the same factor and the load sees the source with the inverse factor. Bellow are two example as ×2 and ×1000 factors.
Hayk

PRR · 24th November 2020, 10:41 PM

New?

kokoriantz · 24th November 2020, 11:22 PM

Old?

PRR · 25th November 2020, 06:40 AM

Broskie (TubeCAD) has written on this in the last year or so. Specifically to work a small tube power stage "master" with a large transistor stage "slave" (sorry for the rude language). He keeps moaning about how few good power amps will work at unity gain. It "can" be done with gain, and he is working at it, but it requires precision gain setting.

I had the same idea back around 2001, and had notes in email, but my email program has lost the key attachment; I didn't get any further than Broskie has anyway.

I was 99% sure I/we got it from The Old Men. But it is not in the Greene/Burr-Brown book nor a few other likely sources.

OldDIY · 07:01 AM

A. M. Sandman Circuits PS-18 & Sandman Error-Takeoff & OTL Amplifiers

Gomes & SE+ & Error Take Off

kokoriantz · 07:58 AM

This is class AA buffer of Technics dating the precedent century.

It was used in CD player output. The principle is far different than my multiplier. The opamp simulates a negative resistance in proportion to the main's resistance, if they are equaled the driving opamp sees the load infinity. If it simulates half of it, the two share the load. See applications The LM1875 for best
Mine is much basic. In fact I asked with class AA type to be given a star if like, only one reader gave, so I remembered Faux French saying , The diy's need to understand how the circuit works. This why I created a simpler than the class AA.
see also Class AA Opamp Schematic

OldDIY · 10:36 AM

Distortion Reduction

OldDIY · 25th November 2020, 10:54 AM

Updating Error-Correction

25th November 2020, 06:57 AM	#5
OldDIY diyAudio Member Join Date: Dec 2009	A. M. Sandman Circuits PS-18 & Sandman Error-Takeoff & OTL Amplifiers Gomes & SE+ & Error Take Off Last edited by OldDIY; 25th November 2020 at 07:01 AM.

25th November 2020, 07:31 AM	#6
kokoriantz diyAudio Member Join Date: Dec 2015 Location: south east asia	This is class AA buffer of Technics dating the precedent century. It was used in CD player output. The principle is far different than my multiplier. The opamp simulates a negative resistance in proportion to the main's resistance, if they are equaled the driving opamp sees the load infinity. If it simulates half of it, the two share the load. See applications The LM1875 for best Mine is much basic. In fact I asked with class AA type to be given a star if like, only one reader gave, so I remembered Faux French saying , The diy's need to understand how the circuit works. This why I created a simpler than the class AA. see also Class AA Opamp Schematic Last edited by kokoriantz; 25th November 2020 at 07:58 AM.

25th November 2020, 10:21 AM	#7
OldDIY diyAudio Member Join Date: Dec 2009	Distortion Reduction Last edited by OldDIY; 25th November 2020 at 10:36 AM.

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24th November 2020, 10:41 PM	#2
PRR diyAudio Member Join Date: Jun 2003 Location: Maine USA	New?

24th November 2020, 11:22 PM	#3
kokoriantz diyAudio Member Join Date: Dec 2015 Location: south east asia	Old?

25th November 2020, 06:40 AM	#4
PRR diyAudio Member Join Date: Jun 2003 Location: Maine USA	Broskie (TubeCAD) has written on this in the last year or so. Specifically to work a small tube power stage "master" with a large transistor stage "slave" (sorry for the rude language). He keeps moaning about how few good power amps will work at unity gain. It "can" be done with gain, and he is working at it, but it requires precision gain setting. I had the same idea back around 2001, and had notes in email, but my email program has lost the key attachment; I didn't get any further than Broskie has anyway. I was 99% sure I/we got it from The Old Men. But it is not in the Greene/Burr-Brown book nor a few other likely sources.

25th November 2020, 10:54 AM	#8
OldDIY diyAudio Member Join Date: Dec 2009	Updating Error-Correction