Simple 200W Amp - 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 25th November 2008, 11:05 PM   #1
diyAudio Member
 
Join Date: Nov 2008
Default Simple 200W Amp

I found a very simple 200W audio amplifier schematic:

http://www.mif.pg.gda.pl/homepages/t...s/simp200W.gif

I actually happen to have a few TDA2030s in a box, hence the interest in this particular schematic. As far as I can tell it's a reasonably solid design. Can anyone spot any immediate problems with this design, or any simple and cheap improvements?
  Reply With Quote
Old 26th November 2008, 10:51 AM   #2
diyAudio Member
 
Join Date: May 2008
The transistors are probably BD707 and BD708, not KD.
According to the datasheet the TDA2030 is limited to 36 V supply voltage, not 44 V.
__________________
If you've always done it like that, then it's probably wrong. (Henry Ford)
  Reply With Quote
Old 26th November 2008, 01:24 PM   #3
diyAudio Member
 
Join Date: Nov 2008
I actually spotted that last night whilst I was looking at the datasheet. I'll use a 30V supply.

As regards the power supply shown, would it not be a bit too noisy for audio purposes? I'd have expected to see an SMPS driving a circuit with this kind of amplification.
  Reply With Quote
Old 26th November 2008, 01:30 PM   #4
diyAudio Member
 
sivan_and's Avatar
 
Join Date: Dec 2004
Location: B'lore/ Calicut India
Send a message via Yahoo to sivan_and
I think the 44volts is absolute maximum for TDA2030 A...version A is high voltage version
__________________
SivanandBalan
  Reply With Quote
Old 26th November 2008, 03:09 PM   #5
diyAudio Member
 
Join Date: Nov 2008
I know I'll need heatsinks for the transistors, but what about the opamps? Not sure what kind of thermal output I should be expecting.
  Reply With Quote
Old 26th November 2008, 03:46 PM   #6
diyAudio Member
 
Stuart Easson's Avatar
 
Join Date: Oct 2002
Location: Santa Cruz, CA
Send a message via MSN to Stuart Easson Send a message via Yahoo to Stuart Easson
Default 200w is perhaps a little optimistic...

Perhaps the 200w is peak, not rms

The power transistors mentioned will pop if you use more than a +/- 30v supply, they are rated 60v...

Most other parameters of the transistors are too small to get 200W from this arrangement, you will simply make nasty smelling smoke.

Fortunately the BD70x transistors are slow, so there is a good chance substituting other slow transistors that are appropriately rugged will get you closer to your goal...Adcom made the GFA1 that was a 'real' 200w RMS BTL amp, it used ~50v rails and 2SB554/2SD424 outputs. I have successfully substituted mj15003/4 to get a little more margin in current and power, seems like you could use them here.

The tda2030 will need to drive the base current of the outputs, to pretty much the full rail voltage, worst case maybe an amp or two. With 30v rails, at half power into 8 ohms, depending on the gain of the transistors the chip will be dissipating 5-10w. It will definitely need a heatsink for even short term operation.

HTH

Stuart
  Reply With Quote
Old 26th November 2008, 04:19 PM   #7
diyAudio Member
 
Join Date: Nov 2008
I'll swap the transistors for MJ15003/4s. Turns out the chips I have are indeed the TDA2030A's. A lucky break for me

As regards the power supply I'll see if I can knock up one that puts out around 40V. I'm actually waiting on delivery of a 75VA 230V primary, 2x 50V secondary transformer that was on sale for only 7.50 because one of the screw holes didn't get punched through when it was manufactured. The normal price is around 20. Bargain!
  Reply With Quote
Old 26th November 2008, 05:39 PM   #8
diyAudio Member
 
Join Date: May 2008
Which is of course not the transformer you will use for that amp, right?
__________________
If you've always done it like that, then it's probably wrong. (Henry Ford)
  Reply With Quote
Old 26th November 2008, 05:42 PM   #9
diyAudio Member
 
Join Date: Nov 2008
Have I missed something? I was planning on building a simple power supply to run it off using that transformer. I don't see the issue.

Edit: Hmm... I think I calculated something incorrectly somewhere. For some reason my calculations say I can pull 15A from the primary without the transformer dying. Er, that's very wrong! I'm off out for a bit, then I'll fix my numbers.
  Reply With Quote
Old 26th November 2008, 06:09 PM   #10
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
Well let's see. 50V transformer (which will make approx 69V DC) with 44V absolute max chip. I can see the flames from here.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  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
Simple, powerful (100W-200W into 8ohm) amplifier schematic needed ddog Solid State 15 11th July 2013 11:04 AM
DIY 200w amp blondfire Solid State 7 1st March 2007 10:35 AM
looking for 200w amp bobby boy Solid State 1 15th March 2003 03:18 PM


New To Site? Need Help?

All times are GMT. The time now is 06:09 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