The input bridge can stay even if you use DC at the input.
I managed to manipulate one of the photos Dani posted when he received the board. It shows it is an LM2575S chip, thus for an absolute maximum of 40V at the input.
NB: You can use this photo in front of the seller and demand a new board or money returned.
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OK... that is crazy anayway... I probably missed something )
The original Amplifier use the same PSU and works... mine burnt grrrr
I will never understand....
OK... that is crazy anayway... I probably missed something )
The original Amplifier use the same PSU and works... mine burnt grrrr
I will never understand....
A likely scenario: An engineer designed the amplifier circuit you have and specified the use of an LM2575HV (60V rating). The company produces for a start such boards with the correct components. After some time, the engineer is busy elsewhere or has left the company.
The company purchasing staff can get LM2575S (40V rating) at a much better price and they are not really aware of the difference. It seems to work. The company produces batches with LM2575S instead and you buy one of these boards. Your amplifier is running with a supply voltage around 40Vdc (27Vac) which is the ABSOLUTE LIMIT for LM2575S. No voltage margin as should be used. One day your LM2575S gives in and burns.
Not at all your fault because you could only rely on their recommendation of 28Vac. The company committed a severe production flaw and must either return your money or give you a new board for free.
Many of us have one of the cheapest TPA3255 boards sold. It was exactly the same mistake with the LM2575. As I recall, it was Chris who realized the mistake on that board. Your board is rather rare and no member knew that the same mistake was repeated here.
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The seller is a chinese guy... I spoke with him and he only proposed me to send me back a LM2575S chipset... I disagree ! So I think I am going to open a Paypal case in order to see if I can get any refund....
I wish this story could help the community ) That is a good thing to know !
Anyway, do you think I can order a LM2575HV instead and ask a specialist to replace it or it's better to get a new LM2575S instead and change the PSU ?
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Another LM2575S component is no good solution. When the LM2575S is replaced, you can still not use your 27Vac transformer.
It is EITHER money back OR another new board.
When we know his choice, we can discuss how to see if the LM2575S can be replaced with an LM2575HV. The replacement itself is not difficult but the moment the LM2575S burned, it may have made damage on other components. That we do not know yet.
It is EITHER money back OR another new board.
When we know his choice, we can discuss how to see if the LM2575S can be replaced with an LM2575HV. The replacement itself is not difficult but the moment the LM2575S burned, it may have made damage on other components. That we do not know yet.
I agree... so the only way to know it is to test. I have now nothing to lose.
I tried to check the board... other components seem to be OK.
I am almsot sure that the seller is going to ask me to send back the board in China at my expense, it's a tip well known in China !!! Because the sellers know that shipping cost is almsot the same price as the board. It sucks.
Can someone confirm I can order now this : ?
LM2575HVS-12 DC-DC Converter Step Down Uin60V uout 12 V 1 A TO263 LM2575HVS-12/NOPB | eBay
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Thanks amigo
We say "pleine nuit" The seller refuses to refund... so I will buy a LM2575HV to test. The scenario was written in advance.
Hi Dani,
Right, if it is bonne nuit it should also be pleine nuit. I'm only faux.
Please concentrate on blocking the PayPal payment. Did you buy the Zero Zone TPA3255 amplifier board on Ebay? If I'm right in my calculations, there may be another reason for the LM2575 Buck converter not to function. Worse than the LM2575S voltage rating issue. I will just check my calculations with the power supply guys first.
Right, if it is bonne nuit it should also be pleine nuit. I'm only faux.
Please concentrate on blocking the PayPal payment. Did you buy the Zero Zone TPA3255 amplifier board on Ebay? If I'm right in my calculations, there may be another reason for the LM2575 Buck converter not to function. Worse than the LM2575S voltage rating issue. I will just check my calculations with the power supply guys first.
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I bought it on Ebay... but got no news from seller. I opened a case and I know it's going to take some long long days... maybe some months.
Anyway : I bought a LM2575HV chip (60V).
Do you think it is going to work ?
If it can help, here a picture of my PSU :
I just bought this amplifier and I wanted to know more about the regulator, opamp and capacitor value
Anyone have information ?
Thanks in advanced
Hi lithoc, your photo is not appearing.
I think need to use Chrome or Firefox browser to view it
https://ae01.alicdn.com/kf/Hfd145c9...igital-Amplifier-For.jpg_640x640q70.jpg_.webp
https://ae01.alicdn.com/kf/Hfd145c9...igital-Amplifier-For.jpg_640x640q70.jpg_.webp
I don't have the unit yet with me now. So sorry I didn't mentioned earlier .
The reason I bought, it's due to the layout of the capacitor(very near to amplifier), changeable opamp, and no Bluetooth for as minimal intereference as possible .
I'm planning to use 48v but wanted to know what regulator it use to prevent damage
The reason I bought, it's due to the layout of the capacitor(very near to amplifier), changeable opamp, and no Bluetooth for as minimal intereference as possible .
I'm planning to use 48v but wanted to know what regulator it use to prevent damage
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