TPA3255 - all about DIY, Discussion, Design etc

[Michelag]

Following your development...
In the meantime let me ask if it's possible to use this amp just as a mere power amp?

Using my marantz as a pre?

Thank you!

 

[irribeo]

Why does it add the aircoils to each pos and neg output after what looks like a standard outputfilter, for sound ???

 

[daniboun]

Hi amigos...

I think is going to be my first and last DIY...
I don't know what happened yesterday but when I switched on the Amp, a chip burnt unfortunately... I am so disappointed (take a look at the last picture)

Anyway some pictures :

The idea was to use a Mini ITX case.

I am now waiting for the seller to make a refund

 

[Michelag]

nice build!
I don't undestand if it has a ventilation fan?

Where did you find a suitable case ?

ps. I'm now looking a Sure AA-AB32313, do you have experience with this? The only drag is the fan, could be loud...

 

[daniboun]

nice build!
I don't undestand if it has a ventilation fan?

Where did you find a suitable case ?

ps. I'm now looking a Sure AA-AB32313, do you have experience with this? The only drag is the fan, could be loud...

This is a fanless board.

The Sure AA-AB32313 is a T amp board. I read this is a really "musical" amplifier and should be a great value... But I never tested it.
The Case is a ITX (computer Case) that I modified myself.

 

[zek]

@daniboun
Have you connected the speakers to an amplifier or any load?
D-class amplifiers must not be switched on without load on the output.

 

[daniboun]

@daniboun
Have you connected the speakers to an amplifier or any load?
D-class amplifiers must not be switched on without load on the output.

I switched on the Amp without any load or speaker connected... But I have some class D amplifiers and never got this kind of issue... The chip completely burnt and broke after powering the amp ! This seems to be a defective board. ??..

As you see see the chip broke and burnt :

 

[vacuphile]

This is in all likelihood the result of overvoltage. The burnt chip 99% sure is an LM2575 buck converter that was exposed to >40V. For these boards, you need to use the HV version of that chip, or keep voltage below 40V.

This is something that should be dealt with under warrenty, but if that doesn't work out, it is repairable with this LM2575HVS-12/NOPB Texas Instruments | Mouser Nederland

 

[vacuphile]

@daniboun
Have you connected the speakers to an amplifier or any load?
D-class amplifiers must not be switched on without load on the output.

This board has a Zobel at the output so it is protected against that, but normally, without a Zobel and high Q output inductors, you are right.

 

[FauxFrench]

I would follow the good advice of Vacuphile and replace the LM2575 IC. It is not difficult. There are good chances that nothing more vital is burned as well. We have all had situations like that.

 

[daniboun]

This is in all likelihood the result of overvoltage. The burnt chip 99% sure is an LM2575 buck converter that was exposed to >40V. For these boards, you need to use the HV version of that chip, or keep voltage below 40V.

This is something that should be dealt with under warrenty, but if that doesn't work out, it is repairable with this LM2575HVS-12/NOPB Texas Instruments | Mouser Nederland

This is werid... I measured myself the Output Voltage of that PSU @ 27V exactly with a Multimeter, so the problem comes from the chip itself. The PSU works great.

in the worst scenario, can you give me a Ebay.fr or Amazon.Fr link since I am living in France, I found this :

LM2575HVS-12/NOPB Texas Instruments, 2 pcs in pack, sold by SWATEE ELECTRONICS: Amazon.fr: Commerce, Industrie & Science

OR

LM2575HVS-12 DC-DC converter step down Uin60V Uout12V 1A TO263 LM2575HVS-12/NOPB: Amazon.fr: Commerce, Industrie & Science

OR

PMIC Dc / Convertisseur Ueing : 60V Uausg : 12V TO263-5 Buck LM2575HVS-12 / Nopb | eBay

 

[daniboun]

I find it in stock here, fast delivery in France, can you confirm this is the right chip please amigos ? :

LM2575HVS-12 DC-DC Converter Step Down Uin60V uout 12 V 1 A TO263 LM2575HVS-12/NOPB | eBay

and also

1pcs LM2575HVS-12 Convertisseur DC/DC buck, step down Ud'entree 60V Usortie 12V | eBay

 

[Kay Pirinha]

I'd prefer a reliable and trustworthy seller like Digikey, Mouser et al.
Best fegards!

 

[vacuphile]

This is werid... I measured myself the Output Voltage of that PSU @ 27V exactly with a Multimeter, so the problem comes from the chip itself. The PSU works great.

That is AC. After conversion to DC it is times 1.4. With some over voltage on the net, it may easily be over 40V DC rectified.

Those chips linked to are right.

 

[daniboun]

That is AC. After conversion to DC it is times 1.4. With some over voltage on the net, it may easily be over 40V DC rectified.

Those chips linked to are right.

I am OK, BUT check out the spec of the board :

And check now the recommended PSU :

300W Toroid Transformer 0-115V 0-115V to 0-28V for TPA3255 amplifier board | eBay

So what is going wrong ???? Am I crazy or the seller is unfair ??

Here the measurements = 27V :

 

[jimk04]

you have 27volts AC, which means approx. 38volts DC.
As mentioned if you have a high mains in your area you may breach the 40v limit of that chip

 

[daniboun]

you have 27volts AC, which means approx. 38volts DC.
As mentioned if you have a high mains in your area you may breach the 40v limit of that chip

Thanks but did you read the board spec ?
So it means that the seller is a liar ? and the chip on it is not adapted...
I asked on page 155 wich PSU should be recommended...

As reminder : board is sold to support 28V AC PSU, don'tmake me wrong ?

 

[daniboun]

So finally amigos... I ask again.. WHAT PSU I REALLY NEED NEXT TIME ?
I should have tried first my SMPS 300RS @ 28V with no risk grrrrrrrrrr

 

[FauxFrench]

Thanks but did you read the board spec ?
So it means that the seller is a liar ? and the chip on it is not adapted...
I asked on page 155 wich PSU should be recommended...

As reminder : board is sold to support 28V AC PSU, don'tmake me wrong ?

Dani, it is not that we say the 28Vac is wrong to use with the board. We have before seen TPA3255 boards specified for up to 50Vdc supply while the board uses a voltage regulator that can as absolute maximum handle 40V. Your voltage chip is seriously burned and it is only to find out what to replace it with.

 

[zek]

....I should have tried first my SMPS 300RS @ 28V with no risk grrrrrrrrrr

Note: This 28V are DC not AC, may not be enough for 3255 board.
Your board need AC power, or you must skip input bridge.