no spike protection allowed - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 11th May 2007, 05:58 PM   #1
diyAudio Member
 
Join Date: Apr 2007
Default no spike protection allowed

is there a good quality high powered chip amp without internal spike protection which i could use in a 250 watt output project.
  Reply With Quote
Old 11th May 2007, 06:29 PM   #2
diyAudio Member
 
Join Date: Oct 2006
I'm not trying to be rude or anything, but what is your reasoning for not wanting spike protection? you could use several lm3886 or lm4780 in bridge and or series configurations to get up to your power requirements, but they still have spike protection. I am very interested to find out what you are planning here.

here's a link to a very nice project

BPA300 Eagle File .BRD - No Catches

good luck
  Reply With Quote
Old 11th May 2007, 07:47 PM   #3
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
OPA549 from Texas Instruments -- bridge two of these -- note that most chipamps have some kind of current protection -- amplifier chips want good heatsinking.

you could also use an LM4702 and parallel some HexFETs -- but you need to get the bias up to a couple of volts (or use Lateral MOSFETs) -- somewhere I posted a schematic from an article that Borbely wrote up for audio amateur.
  Reply With Quote
Old 11th May 2007, 08:07 PM   #4
BWRX is offline BWRX  United States
diyAudio Moderator Emeritus
 
Join Date: Jan 2005
Location: Pennsylvania
Quote:
Originally posted by drummer_Dave
here's a link to a very nice project

BPA300 Eagle File .BRD - No Catches
It has potential to be a nice project. There were a lot of problems with the first design posted by DJexprice.
__________________
Brian
  Reply With Quote
Old 12th May 2007, 10:24 PM   #5
diyAudio Member
 
Join Date: Apr 2007
Default why no spike

i have noticed fluctuations on the scope when certain low frequency music is playing are similar to the fluctuations when the 3886 is clipping. i just wanted to rule out the possibility that spike might be coming on when it is not needed to protect the chip. i do not know enough about this subject to explain this phenomenon other than trial and error. substituting and observing are my best methods at this time
  Reply With Quote
Old 13th May 2007, 02:33 PM   #6
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Default Re: why no spike

Quote:
Originally posted by tryonziess
i have noticed fluctuations on the scope when certain low frequency music is playing are similar to the fluctuations when the 3886 is clipping. i just wanted to rule out the possibility that spike might be coming on when it is not needed to protect the chip. i do not know enough about this subject to explain this phenomenon other than trial and error. substituting and observing are my best methods at this time
What was the thermal impedance of the heat sink you were using? (or can you give us an idea of its approximate surface area).
  Reply With Quote
Old 13th May 2007, 06:52 PM   #7
diyAudio Member
 
Join Date: Apr 2007
the area of copper was 5x12 inches 1/2 inch thick with 11 5x1 fins. the sink temperature never reached 100 f. the only fluctuations occured at roughly 80hz and below into a 12 inch woofer. actual volume was quite "loud". no more specifics since i would not no what to look for. i am only following a hunch that spike might be a little hasty in its activation. it could be something else, but i have good clean response until these parameters come together. this is a new endeavor and i am learning as i go.
  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
OPT Voltage spike protection with zeners bigwill Tubes / Valves 8 17th July 2009 05:24 AM
How much ripple on B+ is allowed? Rundmaus Tubes / Valves 11 16th October 2005 03:19 AM
Anyone use these Spike Feet? m1abrams Multi-Way 2 22nd July 2004 07:54 PM
Blackgate Super-E configuration! Polarized cap allowed? w00t Chip Amps 1 20th June 2004 08:40 AM
How much DC offset allowed in headphone amp? jwb Headphone Systems 2 5th August 2003 12:15 PM


New To Site? Need Help?

All times are GMT. The time now is 04:49 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