Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

What is this Amp design called?
What is this Amp design called?
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
Closed Thread
Thread Tools Search this Thread
Old 28th February 2009, 09:06 PM   #1
packer is offline packer  United Kingdom
diyAudio Member
Join Date: Oct 2006
Default What is this Amp design called?

I have an FBT MAXX 4a powerd speaker which keeps blowing FETS (Q3). See page 3. I have never seen this design before.
especially passing audio through digital Gates See pre amp section.

I would like to know what the design is called and then search for some theory on operation. Also I would like to know what voltages to expect at each junction.

Even with a lamp in series with the ac in it shorts Q3, D5 & U2

The circuit was too big to Upload so link below


All help would be be most appreciated.
Old 28th February 2009, 10:13 PM   #2
infinia is offline infinia  United States
diyAudio Member
infinia's Avatar
Join Date: May 2005
Location: SoCal
It looks like a Class D amplifier output stage.
It's basically a pulse width modulated power switch with a low pass filter.
U2 is a MOSFET driver with high side and low side gate drive.

Check Q4 and for any low impedance on outputs.
If OK, check with O-scope after disconnecting the 60V drain supply.
EDIT>If the otherside is working, use it for a reference.

like four million tons of hydrogen exploding on the sun
like the whisper of the termites building castles in the dust
Old 1st March 2009, 12:11 AM   #3
Cal Weldon is offline Cal Weldon  Canada
diyAudio Moderator
Cal Weldon's Avatar
Join Date: Jan 2004
Location: Near Vancouver
What is this Amp design called?
Mission accomplished, thread closed as requested.
planet10 needs your help:
Let's help Ruth and Dave

Closed Thread

What is this Amp design called?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
what is this called skullkeeper Parts 1 23rd April 2009 11:28 PM
What is this cap called? intensem1rider Parts 6 20th March 2008 05:34 AM
What's it called? Cal Weldon Multi-Way 10 16th June 2007 05:29 PM
a band called Ra Shpoop Music 3 7th July 2005 11:29 AM

New To Site? Need Help?

All times are GMT. The time now is 07:32 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio