LM3886 power consumption in idle/mute mode
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 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
 12th August 2012, 05:51 AM #1 soda74   diyAudio Member   Join Date: Sep 2009 LM3886 power consumption in idle/mute mode Hello together! Since the forum and google search did help, here is my current issue: I measure a power consumption of about 2.6W (mute on) and 2.7W (idle) for one LM3886 in my diy amp. The measurement includes the losses in the psu. The psu provides +/-25V=. Is 2.7W a normal value? Redards.
 12th August 2012, 06:42 AM #2 pinkmouse   diyAudio Moderator     Join Date: Apr 2002 Location: Rotherham, England What does it say in the datasheet? __________________ Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
 12th August 2012, 06:55 AM #3 soda74   diyAudio Member   Join Date: Sep 2009 The datasheet gives you all information about the maximum power consumption/output/dissipation an how to calculate the correct heatsink but it was no help (for me) to figure out the power consumption in idle/mute mode.
 12th August 2012, 07:02 AM #4 pinkmouse   diyAudio Moderator     Join Date: Apr 2002 Location: Rotherham, England Oh, okay, I must be mistaken. 2.6W does sound a tad on the high side, but I suspect most of that is in the PSU. Can you take a measurement of just the chip? __________________ Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
 12th August 2012, 07:43 AM #5 soda74   diyAudio Member   Join Date: Sep 2009 Unfortunately it is not mainly the psu. The losses in the psu should be minimal compared to the consumption of the power stage. The setup: 1x psu, 1x microcontroller+mixer, 1xpower-amp with 3xlm3886. The measuements I already made: - The psu+microcontroller-board alone: 6.85W - All connected, mute on: 14.65W - All connected, mute off: 15.0W - All connected, mute disconnected*: 14,65W *the mute is switched by the micro. This results in approx. 2.6W-2.7W per lm3886. The schematic is mainly the basic datasheet suggestion. The ripple voltage of the psu is <=200mV (peak-peak) for the +rail and <=120mV for the -rail while playing music at low volume @+/-26V.
Mooly
diyAudio Moderator

Join Date: Sep 2007
Quote:
 Originally Posted by soda74 Hello together! Since the forum and google search did help, here is my current issue: I measure a power consumption of about 2.6W (mute on) and 2.7W (idle) for one LM3886 in my diy amp. The measurement includes the losses in the psu. The psu provides +/-25V=. Is 2.7W a normal value? Redards.
Sounds very reasonable. 2.7watts and a 50 volt supply is around 54ma. The data sheet say 50ma as typical and 85ma as a max so its spot on.

Is that what you mean

 12th August 2012, 08:06 AM #7 soda74   diyAudio Member   Join Date: Sep 2009 Thanks a lot! Now I found it too, on page 4 electrical characteristics (what a surprise!): I+ (Note 4) Total Quiescent Power Supply Current VCM = 0V, Vo = 0V, Io = 0A 50 85 mA (max) I am sorry for that unnecessary thread! Sometimes you do not see the wood for the trees. :-/
 12th August 2012, 08:07 AM #8 Mooly   diyAudio Moderator     Join Date: Sep 2007 No problem
 12th August 2012, 09:10 AM #9 pinkmouse   diyAudio Moderator     Join Date: Apr 2002 Location: Rotherham, England I'm glad you found it. I had in my head 40mA, but wasn't certain enough to quote that. __________________ Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
 12th August 2012, 12:15 PM #10 AndrewT   diyAudio Member   Join Date: Jul 2004 Location: Scottish Borders That quiescent current stated in the specification is for normal no-signal operating condition. I cannot see a specification value for current when in mute mode. When I look at the mute circuit on p7, it appears that the mute only attenuates the gain of the input stages. It does not show any connections to the power stages. That's where the big current consumption will be. The earlier stages will probably be more like opamps in current consumption. __________________ regards Andrew T.

 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 Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Site     Site Announcements     Forum Problems Amplifiers     Solid State     Pass Labs     Tubes / Valves     Chip Amps     Class D     Power Supplies     Headphone Systems Source & Line     Analogue Source     Analog Line Level     Digital Source     Digital Line Level     PC Based Loudspeakers     Multi-Way     Full Range     Subwoofers     Planars & Exotics Live Sound     PA Systems     Instruments and Amps Design & Build     Parts     Equipment & Tools     Construction Tips     Software Tools General Interest     Car Audio     diyAudio.com Articles     Music     Everything Else Member Areas     Introductions     The Lounge     Clubs & Events     In Memoriam The Moving Image Commercial Sector     Swap Meet     Group Buys     The diyAudio Store     Vendor Forums         Vendor's Bazaar         Sonic Craft         Apex Jr         Audio Sector         Acoustic Fun         Chipamp         DIY HiFi Supply         Elekit         Elektor         Mains Cables R Us         Parts Connexion         Planet 10 hifi         Quanghao Audio Design         Siliconray Online Electronics Store         Tubelab     Manufacturers         AKSA         Audio Poutine         Musicaltech         Aussie Amplifiers         CSS         exaDevices         Feastrex         GedLee         Head 'n' HiFi - Walter         Heatsink USA         miniDSP         SITO Audio         Twin Audio         Twisted Pear         Wild Burro Audio

 Similar Threads Thread Thread Starter Forum Replies Last Post JozzaG Chip Amps 21 19th January 2012 05:28 PM noah katz Class D 7 31st October 2011 08:01 AM rtill Chip Amps 21 29th August 2009 05:43 AM mudihan Chip Amps 3 21st December 2007 09:23 AM richie00boy Chip Amps 6 18th August 2004 11:26 AM

 New To Site? Need Help?

All times are GMT. The time now is 07:22 AM.