"The Wire AMP" Class A/AB Power Amplifier based on the LME49830 with Lateral Mosfets - Page 230 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 13th March 2014, 12:09 PM   #2291
IanAS is offline IanAS  England
diyAudio Member
 
Join Date: Dec 2004
Location: London
Quote:
Originally Posted by Stammheim View Post
360mA I'd like to know where they have to be measured... between both +-rails? Between +/- and GND?
If that's current through the output mosfets, then it's rail to rail. You take off one supply wire from the PSU to one side of the mosfets and either insert a meter set to current measurement, or insert a low value resistor of sufficient wattage, eg 1 Ohm or something, and measure the voltage drop across it and use Ohms law to calculate the current.

Last edited by IanAS; 13th March 2014 at 12:11 PM.
  Reply With Quote
Old 13th March 2014, 02:16 PM   #2292
diyAudio Member
 
Join Date: Jul 2012
I just noticed I wrote some rubbish, as of cource I measure in series. So I just need the positive rail, for example, which I put the meter into it. Right?
  Reply With Quote
Old 13th March 2014, 06:57 PM   #2293
diyAudio Member
 
Join Date: Jun 2011
Quote:
Originally Posted by Stammheim View Post
Right?
Right...
  Reply With Quote
Old 19th March 2014, 08:14 PM   #2294
diyAudio Member
 
Join Date: Jul 2012
Hi guys,

I hope, anybody can help me...
When powering on my amp it just made "klick" and the SMPS showed a short circuit.
As I understood from the schemata, the P-Mosfet has to be soldered to the -rail, so the left side of the PCB.
Right?
I hope I have not killed neither the mosfets nor the LME

Thanks,

Stammheim
  Reply With Quote
Old 20th March 2014, 10:34 AM   #2295
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Yes, the P channel is connected to the -ve rail.
Yes, the P channel is on the top left of the PCB, next to the -ve labeled terminal.
__________________
regards Andrew T.
  Reply With Quote
Old 25th March 2014, 02:22 PM   #2296
opc is offline opc  Canada
diyAudio Member
 
opc's Avatar
 
Join Date: Oct 2004
Location: Ottawa, Ontario, Canada
How is the bias pot set? It should be turned fully clockwise at startup for minimum current. This is opposite of what you would expect, but it's covered in the assembly manual.

If you had the pot fully CCW, then you would be pulling maximum bias current, which is way too high for the SMPS at startup.

Regards,
Owen
  Reply With Quote
Old 27th March 2014, 12:22 PM   #2297
diyAudio Member
 
Join Date: Jul 2012
Of course fully clockwise.
What I found out is that the LME49830 didn't work.
I seem to have got some defective parts, the LME49830, LME49990...

The other guys work fine till now...
  Reply With Quote
Old 27th March 2014, 12:36 PM   #2298
opc is offline opc  Canada
diyAudio Member
 
opc's Avatar
 
Join Date: Oct 2004
Location: Ottawa, Ontario, Canada
Hi Stammheim,

Where did you source your parts from? That's very concerning if you're having issues with multiple parts.

The only other thing I can think of is that the parts were damaged by ESD. Is your workspace set up in a reasonable manner? Do you have an anti-static mat or wear a wrist strap?

Of all the parts I've soldered (and there have been thousands), I have only ever seen one IC failure, and it was an OPA1632 that had excessively high 3rd order harmonic distortion. I chalked it up to me being careless with ESD, and just replaced the part with one from the same rail, which was fine.

The fact that you've had 4 faulty parts now means something is definitely out of the ordinary, either with your parts supplier, or with the way you're assembling/soldering.

Regards,
Owen
  Reply With Quote
Old 27th March 2014, 05:42 PM   #2299
diyAudio Member
 
Join Date: Jul 2012
Hi Owen,

I got all my parts from Digi Mouser or Reichelt (a German distri). I guess I have killed the first reg by myself and by parallel connecting of both amps to one transformer the other one. The defective regs might have demaged the LME49990's. Soldering and the working place are alright. I soldered my most complex amps (SystemD_2k by Chocoholic, see d-amps) without errors.

The LME49830 was in fact a surprise for me, too. However, at the moment everything is fine, and maybe I'll also find an optimum solution for both LPUHP's, like I wrote in the LPUHP-thread
  Reply With Quote
Old 15th April 2014, 10:23 PM   #2300
diyAudio Member
 
Join Date: Jan 2008
Hi and congratulations for the very nice layout
Is there any PCBs left from the 2nd batch ?
  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
Marriage from "ZEN" - and ordinary class AB topology about HCA - why not realized ?? tiefbassuebertr Pass Labs 2 4th January 2014 04:52 PM
X-Amp (LME49830 + Exicon Lateral Mosfets) danfo098 Chip Amps 28 14th October 2013 04:05 AM
"CA-10", new Single Ended Power amp Device based on Aleph or ZEN ? tiefbassuebertr Pass Labs 1 29th September 2010 06:55 PM
Compound Lateral FET for higher power Class AB amp. Mooly Solid State 17 22nd August 2010 02:13 PM
Improvments to "Tube Headphone Amplifier/Preamp with Relay-Based Input and Power Swi" kipman725 Headphone Systems 4 17th August 2009 06:12 PM


New To Site? Need Help?

All times are GMT. The time now is 05:54 AM.


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