lm1875 - 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 20th May 2006, 06:23 AM   #1
diyAudio Member
 
Join Date: May 2006
Send a message via ICQ to siemensc65
Post lm1875

my lm1875
Attached Images
File Type: jpg 20064271571689333.jpg (20.1 KB, 615 views)
  Reply With Quote
Old 20th May 2006, 08:24 AM   #2
diyAudio Member
 
Circlotron's Avatar
 
Join Date: Jun 2002
Location: Melbourne, Australia
Default high output impedance

I see the loudspeaker current-sense resistor signal gets sent into the feedback network and inverting input. You amplifier will have an output impedance higher than normal. This is not always a good thing because the speaker output will rise a lot at it's resonant frequency.
__________________
Best-ever T/S parameter spreadsheet.
http://www.diyaudio.com/forums/multi...tml#post353269
  Reply With Quote
Old 23rd May 2006, 12:11 AM   #3
preiter is offline preiter  United States
diyAudio Member
 
preiter's Avatar
 
Join Date: May 2006
In a vain attempt to educate myself, I wonder if you wouldn't mind answering a couple of questions about the design.

I don't understand the resistor network on the output of the device. You have a resistor between the speaker output and ground, another in parallel with the speaker and the 10k resistor. What are those for?

Also the two caps on the input, what do those do?

I understand the basics of chipamp circuits, but when they start to get fancy I'm totally lost.
  Reply With Quote
Old 23rd May 2006, 02:23 AM   #4
Leolabs is offline Leolabs  Malaysia
diyAudio Member
 
Leolabs's Avatar
 
Join Date: Dec 2004
Location: Bukit Mertajam
Send a message via MSN to Leolabs
"dian liu hui shu",not bad.How does it sound???
  Reply With Quote
Old 23rd May 2006, 03:28 AM   #5
diyAudio Member
 
Join Date: May 2006
Send a message via ICQ to siemensc65
the pcb on this sch
Attached Images
File Type: jpg 1.jpg (99.4 KB, 388 views)
  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
LM1875 PCB, Which To Use Paswa Chip Amps 264 18th January 2013 09:38 PM
LM1875...how low can you go? Gcollier Chip Amps 7 6th May 2010 03:43 AM
How hot does an LM1875 get? Dominique Chip Amps 15 23rd January 2007 02:13 AM
Lm1875 soundNERD Chip Amps 14 12th October 2003 02:26 AM


New To Site? Need Help?

All times are GMT. The time now is 12:42 PM.


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