help in rectifier diode selection

[necplusultra]

I am looking to build a 20A 13V power supply.

Which diodes should I use for the rectifier bridge?

I've been studying this one: http://www.vishay.com/doc?94242 rated at 30A 30V.

This has 3 pins but I do not know how to connect these in rectifier configuration.

I once built a rectifier with 4 shottky diodes but this one has 3 pins.

please help.

thanks.

[cliffforrest]

Originally Posted by necplusultra

I am looking to build a 20A 13V power supply.

Which diodes should I use for the rectifier bridge?

I've been studying this one: http://www.vishay.com/doc?94242 rated at 30A 30V.

This has 3 pins but I do not know how to connect these in rectifier configuration.

I once built a rectifier with 4 shottky diodes but this one has 3 pins.

please help.

thanks.

You can't.

You would need 2 for a bridge and one would have a common cathode, the other a common anode. Draw a bridge to see what I mean.

Maybe there is another part with common anode?

Or you could use it as a full wave rectifier, but that would ned a centre tapped transformer secondary.

In any case, the ratings are not high enough. You need a higher reverse voltage and at least 3 times the load current rating, depending on the heatsink.

Google full wave rectifier, and do your own math!

[necplusultra]

No wonder I was confused with the pinout.

I think I would be better with this component:

http://www.vishay.com/doc?93563 which is a single phase bridge.

I'm tapping the 0-15 ac from transfo.

Hoping this will be good for my psu.

thanks.

[cliffforrest]

Originally Posted by necplusultra

No wonder I was confused with the pinout.

I think I would be better with this component:

http://www.vishay.com/doc?93563 which is a single phase bridge.

I'm tapping the 0-15 ac from transfo.

Hoping this will be good for my psu.

thanks.

That's more like it! Much easier.

Get a 100V one, then you don't have to worry about calculating the voltage requirement.