inductance multiplier - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th February 2004, 12:27 AM   #1
Account Disabled
 
Join Date: Apr 2003
Location: US
Default inductance multiplier

capacitance multipliers are pretty common. How about inductance multiplier, either in a ps or as a load (more difficult)?

any thoughts?
  Reply With Quote
Old 15th February 2004, 03:46 AM   #2
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
you mean a gyrator?
  Reply With Quote
Old 16th February 2004, 01:52 AM   #3
diyAudio Member
 
Join Date: May 2003
Location: Colorado
Hello -

I think what he means is some type of circuit that could "multiply" the value of a given inductor. This would be especially useful when trying to build an inductor-input power supply filter. Normally the required inductor is so large and heavy that it roughly doubles the overall cost of the power supply. If there were a clever way to use a "small" inductor and "multiply" its action, then you could make an inexpensive amplifier that had inductor-input power supply filtering.

Unfortunately, this is just a wild goose chase.

A "capacitance multiplier" only mimics one aspect of a capacitor -- it's tendency to oppose a change in voltage. However, a "capacitance multiplier" does *not* multiply the energy stored in a capacitor. (If it did, then we could get rid of all the big capacitor banks typically found in high-quality amplifiers.)

So the analog to a "capacitance multiplier" would be a circuit that tends to oppose changes in current -- i.e., a constant-current source. However, this circuit doesn't increase the energy storage. You would still need a big inductor that would store enough energy to supply a constant charging current to the filter caps.

I think the confusion begins with the misleading term "capacitance multiplier".

Hope this helps,
Charles Hansen
  Reply With Quote
Old 16th February 2004, 02:36 AM   #4
Account Disabled
 
Join Date: Apr 2003
Location: US
this is what I had in my mind, conceptually.

you can certainly work out the math to see how this whole thing looks like from V1's point of view and compare that to an inductor.
Attached Images
File Type: jpg ind multiplier.jpg (47.7 KB, 476 views)
  Reply With Quote
Old 16th February 2004, 04:26 AM   #5
diyAudio Member
 
Join Date: May 2003
Location: Colorado
Hello -

You can ignore my previous post. It looks like jackinnj was right and that millwood wanted a gyrator. Here's one link:

http://www.epanorama.net/documents/telecom/gyrator.html

Best regards,
Charles Hansen
  Reply With Quote
Old 16th February 2004, 10:57 AM   #6
Account Disabled
 
Join Date: Apr 2003
Location: US
Quote:
Originally posted by Charles Hansen
Hello -

You can ignore my previous post. It looks like jackinnj was right and that millwood wanted a gyrator. Here's one link:

http://www.epanorama.net/documents/telecom/gyrator.html

Best regards,
Charles Hansen

that's the same set-up as the one using op-amp. Has anyone actually used such a circuitry?
  Reply With Quote
Old 16th February 2004, 11:04 AM   #7
diyAudio Member
 
JensRasmussen's Avatar
 
Join Date: Jul 2002
Location: Denmark - Jutland
Send a message via ICQ to JensRasmussen Send a message via MSN to JensRasmussen
Default Gyrator

Hi,

I use the gyrator for making EQ's in my active x over.

Documentation will be ready soon.

\Jens
  Reply With Quote
Old 16th February 2004, 11:43 AM   #8
diyAudio Member
 
JensRasmussen's Avatar
 
Join Date: Jul 2002
Location: Denmark - Jutland
Send a message via ICQ to JensRasmussen Send a message via MSN to JensRasmussen
Default Ups I forgot this

The schmatics and math

The circuit forms an RCL circuit

C is C1
Attached Images
File Type: jpg gyrator.jpg (16.6 KB, 376 views)
  Reply With Quote
Old 16th February 2004, 12:31 PM   #9
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Default Re: Gyrator

Quote:
Originally posted by JensRasmussen
Hi,

I use the gyrator for making EQ's in my active x over.
a gyrator is used to make the RCL transform from active xo to passive
  Reply With Quote
Old 16th February 2004, 12:56 PM   #10
diyAudio Member
 
JensRasmussen's Avatar
 
Join Date: Jul 2002
Location: Denmark - Jutland
Send a message via ICQ to JensRasmussen Send a message via MSN to JensRasmussen
Default Re: Re: Gyrator

Hi,

passive to active or active to passive does it really make much difference. The circuit I posted acts like an RCL series connection, with the component sizes as noted.

Well I use it in a voltage devider and in the feedback of opamps as a frequency dependent resistor, This creates an EQ..... works great too

\Jens
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
VBE multiplier fglabach Solid State 23 12th June 2009 04:56 AM
Vbe Multiplier Help Please mefistofelez Solid State 2 6th December 2004 06:14 PM
cap multiplier or not? PederBass Solid State 13 23rd March 2004 06:26 PM
Multiplier car amp Kilowatt Solid State 19 7th September 2002 02:40 PM


New To Site? Need Help?

All times are GMT. The time now is 03:17 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2