Infineon MA12070 Class D

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Joined 2002
thank you, from someone who doesn't know enough to get anything from reading the datasheet.
If you will, what in particular do you like about the A8 design compared to some others?
Better late than never. It has many good things like the air core coils, opamps drivings its inputs. Less good is the mechanical noise by some ceramic caps. I sold it today in heavily modified state and already miss it...so I bought another one as it is even cheaper today.

That one will get 1 µF WIMA 2.5mm caps, 3 x OPA1642. Will see if I can solve the mechanical noise of the caps.
 
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Disabled Account
Joined 2002
The newer A02 revision (17-03-2022) of Aiyima A8 has a “mystery” part……..

Got it today and operated the patient directly. Sorry for taking a picture after the mods. It now has 3 x OPA1642 and Wima MKS 1 uF in 2.5 mm pitch. It is breaking in as I write this ;)

Please find the differences.
 

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Founder of XSA-Labs
Joined 2012
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Ahh that’s too bad. Can you remove and install a replacement vs trashing the whole board.

I have only had a Class D amp pop and crack on me one time - a TPA3255 under stress test for high power and I had dummy load on only 1 channel and forgot I was driving input to both. The side with no load was not happy due to back EMF from LC filter.
 
Disabled Account
Joined 2002
It is already trashed. Can’t stand making stuff kaputt.

I think it is the soldering of 4 x 100 nF MKS at the inputs. Forgot to connect my ESD wrist strap. A first and a good lesson. Also it lacked the 6 x 1000/35 bulk caps as I ordered those. Searched and also found a miniscule piece of solder tin but not at the pins so I can’t find a root cause except being in a hurry which is one of the worst reasons.

Gain was lower than with the previous one. Sounded pretty good, better than a vanilla Sabaj A10a. That A10a better stays vanilla ;)
 
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Got the new one and the patient got an operation directly as usual. The patient survived and is playing now. 3 x OPA1642, 6 x 470 uF 35V Panasonic FC, 4 x Wima MKS 1 uF 2.5mm. Good stuff, sounds great with deep and tight bass.

Got it from Aiyima which sells stuff on Aliexpress. Requested the A02 version and got one but it could be that all recent ones being sold are rev. A02.

A casing has been drilled/prepared for a regulated linear PSU 22V 3A (LDO). A bit on the light side but when results are OK a 5A version will follow.
 
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