Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

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 23rd June 2009, 09:26 AM   #411
diyAudio Member
 
Calamaro's Avatar
 
Join Date: Mar 2008
Plenty on Ebay.
This one includes power supply (mine were 2.5A). I bought three from him.
http://cgi.ebay.it/Lepai-TA2020-Clas...262&_trkparms=|301%3A1|293%3A1|294%3A30
  Reply With Quote
Old 23rd June 2009, 01:16 PM   #412
diyAudio Member
 
Join Date: Apr 2007
Quote:
Originally posted by Calamaro
Plenty on Ebay.
This one includes power supply (mine were 2.5A). I bought three from him.
http://cgi.ebay.it/Lepai-TA2020-Clas...262&_trkparms=|301%3A1|293%3A1|294%3A30

Hi Calamaro, great combination ... i also ordered one of these from Techex in ebay ... (and this will arrive in Italy .. ((::-) ).
But i have simple questions :

1st : thank you & diyaudio for your info about modify this amp !

2nd : i normally ordered components from dealextreme (do you know ? great !), but this solder communicate you ALL : e.g :

1) hy boy, we received your payment and now we are preparing all
2) after some days: hy boy we sent your order to Hong Kong
3) the last passage : hy boy , today your pack is envoyed by air mail and it will arrive to your home .....

that's all ! i think this way to buy directly from China in great !

BUT i dont know in what way Techex respect all these think ... so i ask you (and also to other people that know !) some info !

Thank you for your assistance, a risentirci !

FS
  Reply With Quote
Old 23rd June 2009, 01:27 PM   #413
diyAudio Member
 
Calamaro's Avatar
 
Join Date: Mar 2008
I had no problem at all with that seller.
So just wait about 3 weeks
good luck
  Reply With Quote
Old 24th June 2009, 11:57 PM   #414
diyAudio Member
 
MikeHunt79's Avatar
 
Join Date: Aug 2003
Location: Bristol, UK
I really wanted to implement overshoot diodes on mine, as I'm planning to use it in the car with 14.4v input and running 4 ohm speakers, basically worst case scenario for this amp.

After killing a TA2020 IC a while back I figured this would be a worthwhile mod (along with overcurrent protection by removing zener).

I made a start today, and I should be able to finished it tomorrow, but I was wondering will this work ok? I'm implementing it in the same was as schematic on the TA2020 datasheet...

I've only done one channel so far:
Click the image to open in full size.

The diodes do not touch the bottom of the case, I may add a little hot glue once finished tho to be on the safe side.



I was thinking about using the spare holes holes on the bottom left to do this until I realised the tracks are after the 10uH diodes...
  Reply With Quote
Old 25th June 2009, 02:59 AM   #415
col is offline col  Australia
diyAudio Member
 
col's Avatar
 
Join Date: Feb 2008
Location: Melbourne, Victoria, Australia
Mike, very interesting. let us know if it works

col.
__________________
http://www.minirig.org.au
  Reply With Quote
Old 25th June 2009, 09:56 AM   #416
diyAudio Member
 
MikeHunt79's Avatar
 
Join Date: Aug 2003
Location: Bristol, UK
Quote:
Originally posted by col
Mike, very interesting. let us know if it works

col.
Haha, that's the thing, I won't really know if it works or not... I guess if I get no sound after the mod then I know something weird is going on...

I'm just making the circuit a little more like the circuit on the tripath datasheet.
  Reply With Quote
Old 25th June 2009, 11:50 AM   #417
magixz is offline magixz  Singapore
diyAudio Member
 
Join Date: Apr 2009
Got my Lepai LP-2020 in a brilliant Anodised RED...
I love it...
Got to study the circuit before modding...

Tried with my "Arjen modded" Topping TP20 with quality components,
there was some distortion with the Lepai and the clarity is not there...

I'll change the op-amp first...
I have the NE5532, TL072C and JRC4456AD to try out with...

So far, I like the TL720P for low noise and High input impedence...
Can refer to this page for more op amp info...
http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm
  Reply With Quote
Old 25th June 2009, 12:17 PM   #418
col is offline col  Australia
diyAudio Member
 
col's Avatar
 
Join Date: Feb 2008
Location: Melbourne, Victoria, Australia
Quote:
Haha, that's the thing, I won't really know if it works or not... I guess if I get no sound after the mod then I know something weird is going on...
Mike, looking at your photo I think your soldering them to the wrong place? THe undershoot diodes go to gnd. The overshoot diodes go back to the pins on the chip (pin 25 and pin 22).

Quote:
Tried with my "Arjen modded" Topping TP20 with quality components, there was some distortion with the Lepai and the clarity is not there...
magixz, I think changing the opamp is the least effective mod you can do. if you want to reduce noise start with changing the resistors, change them all for 1% metal film. Then the pots and caps.

col.
__________________
http://www.minirig.org.au
  Reply With Quote
Old 25th June 2009, 12:41 PM   #419
diyAudio Member
 
MikeHunt79's Avatar
 
Join Date: Aug 2003
Location: Bristol, UK
Quote:
Originally posted by col


Mike, looking at your photo I think your soldering them to the wrong place? THe undershoot diodes go to gnd. The overshoot diodes go back to the pins on the chip (pin 25 and pin 22).
Well, I was hoping I hadn't soldered them in the wrong place, so I'm glad I posted a pic now.

On the pics I posted above, VDD is on the left, and the points I have soldered to on the right go back to the pins 21 and 23. I didn't want to solder directly to the pins as it's very tight around that area.

Now I've only got to do the other two pins:
Click the image to open in full size.
  Reply With Quote
Old 25th June 2009, 12:45 PM   #420
col is offline col  Australia
diyAudio Member
 
col's Avatar
 
Join Date: Feb 2008
Location: Melbourne, Victoria, Australia
if you look at the tracks going into the center pairs of diodes in this photo, i think thats what you need:

http://pix.minirig.org.au/main.php?g2_itemId=1093

col.
__________________
http://www.minirig.org.au
  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
New ta2020 pcb'S ArjenShenzhen Vendor's Bazaar 98 14th November 2012 11:39 AM
Ta2020 Bengali Class D 0 29th September 2007 05:28 AM
Eb-ta2020 opentop Class D 16 30th May 2005 07:42 AM


New To Site? Need Help?

All times are GMT. The time now is 06:23 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