Full wave rectifier with UF4004 or HER205 regarding initial charge current

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geotFM

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Hello.I am making a simple 0.5A /35V psu with a 24Volt AC transformer ,4 diodeS UF4002 and a 2200uF capacitor. I was considering the initial charge current and if the diodes are ok to handle it or should i move to something like HER205? Simulating with a 100 ohm load to get an idea of the current pulses in each diode i got the image below.So how i select a diode with respect to these simulation pulses? UF4002 Datasheet says :

IFRM Repetitive peak forward current of 10A
IFSM Non-repetitive peak forward current of 30A
 

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Hi,

Which datasheet are you referring to? Post a link.

The Vishay one does not specify "repetitive" peak forward current of 10A.

To your diagram:
There is a single peak of 21A. It does not repeat, thus it is non-repetitive.
There are 3A peaks. They do repeat.

So the your non-repetitive is below specified 30A and also the repetitive peaks are below specified 10A.

The Vishay datasheet Fig.2 shows that it can even withstand 6 consecutive peaks of 21A.

Klaus
 
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