Insight request: Parallel 4780 - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 24th February 2005, 01:20 PM   #11
diyAudio Member
Join Date: Dec 2004
Location: Not quite the middle
Doh! thanks guys, I appologize for the silly mistakes I should have double checked the art work again.
I am currectly reading the snubber thread thrying to figure out what I should be doing. But I don't have an L on the baord, should I?
Attached Images
File Type: jpg 120w v.3 complete.jpg (93.8 KB, 134 views)
  Reply With Quote
Old 24th February 2005, 01:31 PM   #12
Alcaid is offline Alcaid  Norway
diyAudio Member
Alcaid's Avatar
Join Date: Nov 2003
Location: Klepp
Just remember that the trace after your output resistors will carry twice the current. Output current limit for the LM4780 is 11.5A each channel. 23A peak, but the trace won't dissipate more than RMS (23A/sqrt(2) = ) 16.3A.

Use the Overture Design Guide 1.5 located here to see what current the traces must handle at your supply voltage.
  Reply With Quote
Old 24th February 2005, 09:14 PM   #13
diyAudio Member
Join Date: Dec 2004
Location: Not quite the middle
I tried to use the calculators, it's a lot more involved than I first thought and I still have to figure out how heavy my boards are I'm going to use. I guessed at 1oz at least it's a safe assumption. A couple of things I gleaned from the National data sheet, firstly I can make short "nubs" from pins to tie my much heavier tracks to like I did for the outputs. Also my trace after the power resistors needs to be huge so I just laid down the biggest feasible area to minimize resistance and act as a heat sink.

Would an 18V dual secondry transformer make more sense? This will go into 4 ohms, it would bring my current and heat sinking requirements to something much more realiastic.
Attached Images
File Type: jpg 120w v.4.jpg (97.1 KB, 111 views)
  Reply With Quote


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
Larger System Prebuild Insight nukaidee Multi-Way 5 14th June 2009 04:24 AM
Toroid output voltage for 4780 parallel? zdr Chip Amps 20 25th February 2008 07:33 PM
4780 stereo, parallel, bridged, single sided gmphadte Chip Amps 12 12th March 2007 11:42 AM
mic pre opamp options NE5532, LM833, LF353.. any insight? evertestmuse Instruments and Amps 1 23rd February 2004 01:34 PM

New To Site? Need Help?

All times are GMT. The time now is 04:13 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2