LT4320 based active rectifier

[Frederico Acardi]

Do you need to add snubber rc like with a standard diode bridge or there is no ringing with this solution ?
What is the definitive answer ?

 

[nautibuoy]

Do you need to add snubber rc like with a standard diode bridge or there is no ringing with this solution ?

See post #1106

 

[Frederico Acardi]

Hi thank you, i have already read it, but is it the definitive answer ? because he said 'many guys have said'. But was it tested ?

 

[bambini]

Hi,
Is it possible to operate the LT4320-based active rectifier with a voltage higher than this 72 V?

 

[nautibuoy]

Hi thank you, i have already read it, but is it the definitive answer ? because he said 'many guys have said'. But was it tested ?

Is there ever a definitive answer? I just trusted Prasi's experience and took his suggestion.

 

[nautibuoy]

Hi,
Is it possible to operate the LT4320-based active rectifier with a voltage higher than this 72 V?

IIRC correctly the answer is 'no' for this board but higher voltage 'ideal regulators' are possible - check out the group buy threads of DIY member 'tvicol'

 

[tubee]

Interesting idea this ideal rectifier

For an class A amp (1.5A idle current) with 2x 15V AC to be rectified, should i get the SMD version or better the Through hole one ?

 

[prasi]

Hi, any version (SMD /THT rectifier ) would work equally well.
Or even the CRC PSU PCB with LT4320 will make a complete PSU.
regards
Prasi

 

[tubee]

Ok thanks Prasi
With CLC filter of 31000 uF 3,5 mH 31000 uF wich mosfets in SMD do you suggest ?

 

[prasi]

Ok thanks Prasi
With CLC filter of 31000 uF 3,5 mH 31000 uF wich mosfets in SMD do you suggest ?

Either SMD or THT both will work.
I have few SMD boards, even few THT.. if you need them.
The schematic posted in the begineeing of thread gives a list of possible mosfets.
Low RDSon, high VDs, Vgsth 2-3 V, and Qg, less than 30 or 50 Nc

 

[guglielmope]

Hello,
I've the boards, now I need mosfets. Anyone can suggest me good one, not too expensive for a 35VAC transformer on Digikey?
Regards
Guglielmo

 

[prasi]

Hello Guglielmo,
Here the link to sch that give some options of mosfets. Do check out.
https://www.diyaudio.com/community/threads/lt4320-based-active-rectifier.336572/post-5789966Once you place your 2-3 choices here, I can find out which will be best for you.

 

[guglielmope]

What about:

STP110N8F6​

 

[prasi]

Qg is too high at 150nC, look for something in the vicinity of 50nC or lower

 

[randytsuch]

Qg is too high at 150nC, look for something in the vicinity of 50nC or lower

FWIW, I picked the SUP70060E-GE3 for a low RDSon, current and voltage were fine, and its in stock at Mouser.
Also not as expensive as some other options.

It has a Qg of 53.5 nC, so seems like a reasonable choice.

 

[guglielmope]

Hello,
I must by on Digikey.
I'll use with 24VAC 3A load
What about:

https://www.digikey.it/en/products/detail/infineon-technologies/IRL530NPBF/811878or
https://www.digikey.it/en/products/detail/vishay-siliconix/IRL540PBF/812025
Thanks
Guglielmo

 

[Vunce]

Fellas,
Go to post #1 and pull up the schematic. Prasi included a list of MosFet possibilities. If none of them are in stock, look for alternatives with similar specs.

 

[prasi]

FWIW, I picked the SUP70060E-GE3 for a low RDSon, current and voltage were fine, and its in stock at Mouser.
Also not as expensive as some other options.

It has a Qg of 53.5 nC, so seems like a reasonable choice.

yes. its nice..

 

[Dan K]

Hello all. Can someone please explain why we need the small 1uF cap? Is it there solely to. Protect the LT4320? Will the rectifier run perfectly well without it?

Thanks.

 

[Vunce]

Page#7 of Datasheet
https://www.analog.com/media/en/technical-documentation/data-sheets/4320fb.pdf