L7 MOSFET AMP - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Vendor's Bazaar

Vendor's Bazaar Commercial Vendors large & small hawking their wares

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 21st December 2011, 01:14 PM   #1
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
Default L7 MOSFET AMP

I designed a small power amplifier。
It uses a pair of VISHAY IRFP240 IRFP9240。
It uses the CFP input, and the suspension of the output, similar to LME49830 structure.
It works in very stable.
In the +-56V voltage.it is can out 150W 8R。
PCB board area 63*78MM only
Attached Images
File Type: jpg 2.jpg (280.6 KB, 2505 views)
  Reply With Quote
Old 21st December 2011, 05:25 PM   #2
diyAudio Member
 
astankov's Avatar
 
Join Date: Dec 2009
Location: Pernik
Any chance for schematic now?
It is pointless to make such threads without schematics and only one or two pictures. If this is a commercial product and you don't want to share it only to show the beautiful PCB (actually is very beautiful!) there is a thread for pictures and it will be better to post more of them.
I'm very curious about the schematic because I'm IRF lover so if there is any chance to see it will be very happy.

Best regards!

Last edited by astankov; 21st December 2011 at 05:45 PM.
  Reply With Quote
Old 22nd December 2011, 02:14 PM   #3
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
Do not worry.

This circuit can be a good power play IRF FET.

I can briefly explain.

It uses the CFP transistor input stage. Single-ended voltage amplification.

Internal structure similar LME49830, suspension of driving.

It can work very high frequency, and waveform perfect.

I tested with the 2700K HZ.

Does not appear as an ordinary FET amplifier instability phenomenon.
  Reply With Quote
Old 22nd December 2011, 02:20 PM   #4
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
I will try to design better quality amplifier, and they are very cheap.

I would like to include not only an actual amplifier circuit, but also includes parts of the performance and parameters. I think this is a whole.

Will be used only truly understand.
  Reply With Quote
Old 1st January 2012, 12:49 PM   #5
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
Please refer to the circuit.
Attached Images
File Type: jpg 无标题.jpg (130.3 KB, 2194 views)
File Type: jpg ljm_40_36_30fb8980b086c5d.jpg (29.9 KB, 2038 views)
  Reply With Quote
Old 1st January 2012, 01:04 PM   #6
CBS240 is offline CBS240  United States
diyAudio Member
 
CBS240's Avatar
 
Join Date: Aug 2005
Location: K-town
Hi

I see I'm not the only one that uses totem pole BJT driver stage for each output FET gate. I do prefer the totem pole driving stage always stays well within class A. Using simple diode bias may cause one of the devices to leave class A during very fast transient output current signals, also it requires thermal feedback to the diodes because without the degeneration of an emitter resistor, thermal runaway can destroy a small signal device in a few blinks of the eye. I use 3 diodes and an emitter resistor on the inside BJT to set bias above the largest charge current needed to operate the FET. Many semi-fab companies make triple diodes in a 6 pin SMD package.
__________________
All the trouble I've ever been in started out as fun......

Last edited by CBS240; 1st January 2012 at 01:08 PM.
  Reply With Quote
Old 1st January 2012, 01:06 PM   #7
diyAudio Member
 
Join Date: Dec 2010
Please post schematic and pcb layout as many diy enthusiasts will like to build the same. Extremely professional pcb does not look diy product.
  Reply With Quote
Old 1st January 2012, 02:32 PM   #8
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
Quote:
Originally Posted by CBS240 View Post
Hi

I see I'm not the only one that uses totem pole BJT driver stage for each output FET gate. I do prefer the totem pole driving stage always stays well within class A. Using simple diode bias may cause one of the devices to leave class A during very fast transient output current signals, also it requires thermal feedback to the diodes because without the degeneration of an emitter resistor, thermal runaway can destroy a small signal device in a few blinks of the eye. I use 3 diodes and an emitter resistor on the inside BJT to set bias above the largest charge current needed to operate the FET. Many semi-fab companies make triple diodes in a 6 pin SMD package.
I am using IRF610 as the bias voltage provided. And with the output stage FET to maintain the same temperature.
  Reply With Quote
Old 1st January 2012, 02:33 PM   #9
ljm_ljm is offline ljm_ljm  China
diyAudio Member
 
Join Date: Sep 2006
Quote:
Originally Posted by katiyar View Post
Please post schematic and pcb layout as many diy enthusiasts will like to build the same. Extremely professional pcb does not look diy product.
If you have a L7. You will find the above parameters in detail. L7 is a very simple DIY AMP.
  Reply With Quote
Old 2nd January 2012, 12:38 PM   #10
CBS240 is offline CBS240  United States
diyAudio Member
 
CBS240's Avatar
 
Join Date: Aug 2005
Location: K-town
Quote:
Originally Posted by ljm_ljm View Post
I am using IRF610 as the bias voltage provided. And with the output stage FET to maintain the same temperature.
Hi
My comments is in reference to the TO-92 driver stage(s), the undegenerated comp class A BJTs that are detached from the diodes that bias them, not the Vgs multiplier bias control for the FETs.
__________________
All the trouble I've ever been in started out as fun......
  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
kicker l7 help Chaoticdopey Subwoofers 5 10th December 2010 12:52 PM
kicker L7 Rebuildable? scampo77 Subwoofers 6 16th June 2009 11:57 PM
Kicker L7 rebuild audiobahnkid592 Car Audio 13 16th June 2009 06:58 PM
kicker L7 rebuildable? scampo77 Car Audio 1 16th June 2009 01:51 PM
Kicker L7 skooter Car Audio 5 25th September 2008 11:36 PM


New To Site? Need Help?

All times are GMT. The time now is 04:26 AM.


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