Go Back   Home > Forums > >

Solid State Talk all about solid state amplification.

Understanding an active full-wave rectifier
Understanding an active full-wave rectifier
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
Old 26th September 2009, 06:19 AM   #1
300b is offline 300b  Israel
diyAudio Member
 
Join Date: Aug 2008
Default Understanding an active full-wave rectifier

Hi Guys,

Since you were all very kind and helpful last time I had some trouble understanding a circuit, I guess it'll be a good idea to ask for your help once more.

I'm having some trouble understanding the following circuit:
An externally hosted image should be here but it no longer works. Please upload images instead of linking to them to prevent this.

Its from 'The Art of Electronics' page 222. Can you please help me understand it (a detailed explanation will be very much appreciated).

I've started by saying there is 0V at both inverting inputs (since the op-amp will do whay ever it can for it to happen), but I'm not sure where to go to next.
  Reply With Quote
Old 26th September 2009, 02:30 PM   #2
djoffe is offline djoffe  United States
diyAudio Member
 
Join Date: Oct 2008
Default how it works...

top op-amp is a summer...the gain from Vin is -1.
The gain from the HW node is -2.

bottom op-amp is a half wave rectifier. The gain from the input to its output, the HW node, is -1 for positive input signals, and 0 for negative input signals.

Now, consider Vin>0 at the input. The overall output is
Vin*-1+Vin*-1*-2=+1*Vin.

For Vin <0 at the input, we have:
Vin*-1+0*Vin=-Vin

For positive Vin (Vin>0), the gain is +1, so the output is positive.
So for negative Vin (Vin<0), the gain is -1, so the output is positive.
Attached Images
File Type: bmp fullwave.bmp (81.0 KB, 183 views)
  Reply With Quote
Old 29th September 2009, 04:33 AM   #3
300b is offline 300b  Israel
diyAudio Member
 
Join Date: Aug 2008
Sorry for the delayed response.

Thank you very much for the explanation, its a very nice way of looking at this circuit, didn't cross my mind
  Reply to this post

Reply


Understanding an active full-wave rectifierHide this!Advertise here!
Thread Tools

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Bridge rectifier vs Full wave rectifier hilbert_mostert Tubes / Valves 4 28th April 2009 08:26 PM
Full Wave Rectifier dscrobe Tubes / Valves 6 1st July 2008 07:35 PM
6bBYGA x2 as full-wave rectifier? GordonW Tubes / Valves 2 19th December 2007 05:17 PM
Full wave vs full wave bridge rectifier jeff mai Parts 31 11th February 2005 11:43 PM


New To Site? Need Help?

All times are GMT. The time now is 03:50 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Copyright ©1999-2021 diyAudio
Wiki