Signetics NE540 / SE540 power amplifier - 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
Thread Tools Search this Thread
Old 6th October 2006, 08:11 PM   #1
ash_dac is offline ash_dac  United Kingdom
diyAudio Member
Join Date: Jan 2005
Location: UK
Default Signetics NE540 / SE540 power amplifier


Has anyone built a NE540 based power amplifier?

I'm looking at a Signetics NE540 power amplifier design in Audio IC op-amp applications by Walt Jung. The design is referenced to Signetics Corp' and by my understanding is a NE540 op amp and Sziklai pair outputs with local feedback paths. Could be wrong though!

Note: I wasn't sure whether to post to solid state or chip amp forum!
  Reply With Quote
Old 14th February 2013, 06:05 PM   #2
diyAudio Member
fooeywuffle's Avatar
Join Date: Nov 2009
Location: Southern California

I made a lot of them back in the 70s. 35 watts a channel.
  Reply With Quote
Old 14th August 2015, 09:51 PM   #3
Maitchy is offline Maitchy  New Zealand
diyAudio Member
Join Date: Feb 2006
Location: Christchurch
I have used NE540L's in the past, and still have some chips. Good idea having the output stage of an opamp split to allow a Vbe multiplier, very good slew rate, but you do have to be careful with high frequency stability (be careful with layout; don't reduce the closed-loop gain too much to reduce THD), and it is a bit harder to keep crossover distortion low as the temperature changes (Vbe ref cannot be in thermal contact with output transistors in the datasheet's recommended circuit, but you can still disable that and supply your own external transistor). They did have a circuit option that had a good fold-back limiting cutout feature as far as I can recall. The SE540 has a higher voltage rating, but I have only tried NE540's.
  Reply With Quote
Old 14th August 2015, 10:00 PM   #4
infinia is offline infinia  United States
diyAudio Member
infinia's Avatar
Join Date: May 2005
Location: Californication

yes indeed the 1st chip amps
TO-5 can with external PNP / NPN pass devices > ~25W if memory serves
I made a few pair in high school using the supplied artwork shown on the app book (hard-back). they are prone to oscillation unless bypassed very well. +/- 25 V implies 50-60V bipolar process

I also built a DC/DC converter to power them using a push-pull on a 1.25 " ferrite toroid
like four million tons of hydrogen exploding on the sun
like the whisper of the termites building castles in the dust

Last edited by infinia; 14th August 2015 at 10:14 PM.
  Reply With Quote
Old 18th August 2015, 06:22 PM   #5
diyAudio Member
fooeywuffle's Avatar
Join Date: Nov 2009
Location: Southern California
I made quite a few amps using NE540s in the 1970s. I didn't have any problems with them. Used 30 amp output transistors ECG 130 and 131. Got 35 watts at 8 ohms. Never tried using 4 ohm speakers since I didn't have any. No oscillation problems.
  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
Rockford Fosgate Power 20001 bd amplifier power rating?? pachoorion Car Audio 8 8th May 2011 11:49 PM
Power transformers versus amplifier output power..what is your option? destroyer X Solid State 38 9th May 2009 06:23 PM
McIntosh Power Amplifier Power Guard johnnyrt Solid State 2 23rd August 2007 11:22 PM
Output power for a power amplifier Progg70 Solid State 33 10th September 2006 09:44 AM
Amplifier 3000 Wats Rms Power + Smps Higcht Power Bestiality MARAVILLASAUDIO Class D 1 5th November 2004 05:06 PM

New To Site? Need Help?

All times are GMT. The time now is 07:24 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
Copyright 1999-2015 diyAudio

Content Relevant URLs by vBSEO 3.3.2