Comprimize of power supply voltage - 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 13th June 2003, 08:17 PM   #1
cm961 is offline cm961  Canada
diyAudio Member
cm961's Avatar
Join Date: Jun 2001
Location: Peterborough, Ontario
Default Comprimize of power supply voltage


I plan on building a supply which will power a bridged/paraelle LM3886T similiar to the one in the application note (National's AN-1192) which calls for a +/- 42V. Howevevr, I also want to power 4 individual GainClones using LM3875 or LM1875 chips. Now of course +/- 42V is too much for a GainClone. So I guess what I'm asking is whats considered the uppermost supply voltage that can be used in a GainClone?

  Reply With Quote
Old 13th June 2003, 08:29 PM   #2
diyAudio Member
platenspeler's Avatar
Join Date: Jan 2003
Location: Netherlands

For the LM-1875 this is even lower than for the LM3875. The LM1875 has an absolute maximum (datasheet) of +/- 30 Volts DC. But I used a power transformer of -16.5 and +16.5 Volts AC which results in +/- 23 Volts DC after rectification.

The LM3875 has an absolute maximum rating of 84 Vdc rail-to-rail (+/- 42 Vdc), but most on this formum use lower values in order to connect speakers with lower impedance to their gainclone. I used a dual 22 Vac transformer of Plitron/Amplimo which provides +/- 31.1 Vdc after rectification.

Therefore, I do not think it is a good idea to share transformers for these different chips unless you want to put the bridgeclone on a lower supply voltage intentionally.

(project and Power Supply background on

  Reply With Quote
Old 13th June 2003, 08:41 PM   #3
diyAudio Member
Join Date: Sep 2002
Location: Sweden
You might also consider using the 3886 also for the Gainclones
and the problem will vanish.
  Reply With Quote
Old 16th June 2003, 08:35 PM   #4
cm961 is offline cm961  Canada
diyAudio Member
cm961's Avatar
Join Date: Jun 2001
Location: Peterborough, Ontario
Cool, thanks for the help guys. I'll probably just use all LM3886, as its going in a car anyways.

  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
Split Voltage Switching Power Supply for Power Amp vectorplane Swap Meet 2 23rd April 2011 11:48 PM
DDD mfg co High Voltage power supply? firechief Tubes / Valves 3 10th March 2009 02:07 AM
high voltage power supply leemajcool Power Supplies 3 5th August 2007 11:40 AM
help! power supply voltage issue jlg4104 Tubes / Valves 15 2nd December 2002 06:35 PM

New To Site? Need Help?

All times are GMT. The time now is 05:38 PM.

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