diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Chip Amps (http://www.diyaudio.com/forums/chip-amps/)
-   -   If TDA7294 Can work in 30V AC transformer (http://www.diyaudio.com/forums/chip-amps/167875-if-tda7294-can-work-30v-ac-transformer.html)

guaxian 2nd June 2010 03:48 AM

If TDA7294 Can work in 30V AC transformer
 
TDA7294 PDF says it max V. is 40V DC, But my transformer is double 30V AC, Will it broken?
Anybody try to use hight voltage in use:confused:

abraxalito 2nd June 2010 05:09 AM

Yep, you'll definitely blow it up with such a high voltage transformer. Even the TDA7293 which can stand 50V will be a tad marginal with such a transformer, unless its regulation is 7% or better.

guaxian 2nd June 2010 05:26 AM

Thanks Abraxalito, But I will still keep trying, If Broken
I will reply here.

danielwritesbac 6th June 2010 05:57 AM

You could use your transformer in Center Tap config with just 2 diodes (total), in the center tap specific full wave rectifier. . . pretty much just exactly like a vacuum tube rectifier.
Link ---> File:Fullwave.rectifier.en.png - Wikipedia, the free encyclopedia
This makes approximately 22vdc,0,22vdc after rectification

or, you could use a regulated power supply

guaxian 8th June 2010 07:01 AM

Thanks for reply!

vedmitraa 11th June 2010 06:28 AM

Hi everybody, This is Vedmitrasharma from City of Tajmahal . Can somebody guide me how to parrellel T D A 7294 I.C.s to get more current power to drive subwoofers as the have done with L M 3886 in Berringer moniter box with 3 I.C.s .regards everybody .waiting for reply

guaxian 23rd June 2010 01:29 AM

Quote:

Originally Posted by vedmitraa (Post 2213339)
Hi everybody, This is Vedmitrasharma from City of Tajmahal . Can somebody guide me how to parrellel T D A 7294 I.C.s to get more current power to drive subwoofers as the have done with L M 3886 in Berringer moniter box with 3 I.C.s .regards everybody .waiting for reply

I just had TDA7293 with 3 I.C.s. Working fine in +/- 45V!

guaxian 23rd June 2010 01:32 AM

Hi all, I have input 30V AC on TDA7294, Working for two weeks,
It's working fine and the TEMP is no hight, TDA7293 may be safe on +/- 42V DC.

masood 16th May 2012 05:18 PM

Quote:

Originally Posted by guaxian (Post 2224452)
I just had TDA7293 with 3 I.C.s. Working fine in +/- 45V!

hi guaxian,
can u send me this 3 ic shcematic and pcb details thanks

ric-paul 16th May 2012 07:25 PM

The first three words of the TDA7294 specheet: "ST", "TDA7294" and "100V".
I would have no problem running it on a 2x30V~ transformer.

Infact I did...:D

I made a PCB for the class G/H application of the TDA7294 and this is in the specsheet as being run of off +/-20 and +/-40. I had a custom transformer wound for it with a 2x30V secondary (and 2x15). It worked for a few months, and then it indeed blew up :D. But I have no indication the voltage caused it.:p It had other issues, like clipping at 25V with a +/-20 and +/-40V supply :confused:

As for paralleling it: it can be done (there\'s a commercial amp discussed on here somewhere with (iirc) 12 bridged sets of TDA7294's that can be paralleled to one channel).

But the TDA7293 has a special feature for it (never looked into it as I am stuck with a load 7294's due to the above mentioned failed project) but supposedly it is like a master-slave function and doesn't even need extra resistors. So it would be far easier to do it with a 7293.


Edit: another quote from the specsheet:
Quote:

The TDA7294 is a monolithic MOS power amplifier
which can be operated at 80V supply voltage
(100V with no signal applied) while delivering output
currents up to 10 A.


All times are GMT. The time now is 06:18 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