Integrated Rectifier Bridge VS Rectifier Diodes

[Sci]

Hi

I started looking at amplifier chips a few days ago, and found this site. It has been a great source of help, just reading it.

Now to my question. It seems to me that most people use four diodes for rectification (is that a word in english?). Is there a reason to not use a integrated rectifier bridge (if that's what it's called in english, what I mean is a chip with four diodes connected as a rectifier bridge)?

Erik

[ajju]

You can see the bridge here. There has been a lot of discussion on the use of normal rectifier diodes vs Shottky rectifiers, or high speed diodes. But personally I like the bridge, basically anything thats nicely packaged and closely thermally coupled will have an edge over discretes is my belief. So...
What is not shown in the PCB is provision for some snubbers.. I plan to put them directly on the pins, on the solder side.

ajju

[gchackle]

Use the integrated bridge rectifiers. Less work, usually higher current rating, cheaper, easier to replace, etc.

There's really no reason to use seperate diodes.

Some people claim that faster diodes work better, but this is 60Hz - it doesn't matter since even the slowest diode in the world will be many times faster than this. Snubbing caps across the pins is a good noise prevention measure if you feel like it, usually not required but cheap so why not.

Some also claim that it makes a "sonic" difference if you get the individual diodes. These are usually the same people that claim that a $500 oxygen-free copper "super duper" mains power cord to feed your equipment will improve the sound of your amp.

But they are right to some degree -> it does make a sonic difference. No sound will be coming out of your speakers when you can't afford to pay the electric bill becuase you spent your money on expensive high speed diodes

[Doovieman]

Just use a bridge. I'm sure that some people claim that their "fast action" diodes make a sonic difference, but a bridge works just fine...you can also get a "fast action" bridge if you so choose.

[Sci]

What about paralell connection of two bridges? Any problems there?

Erik

[Doovieman]

No problem at all.

[fdegrove]

Hi,

What about paralell connection of two bridges? Any problems there?

What do you expect to gain from putting two bridges in // ?

Cheers,

[Jay]

Originally posted by gchackle
There's really no reason to use seperate diodes.
Some people claim that faster diodes work better, but this is 60Hz - it doesn't matter since even the slowest diode in the world will be many times faster than this. Snubbing caps across the pins is a good noise prevention measure if you feel like it, usually not required but cheap so why not.

Hehehe And why with the cheap snubber caps? Some people don't rely on numbers. I have been happy using MUR120/140/160/480/860 etc. May be it is not because the 50ns, may be it is just because Motorolla has great machines. But who cares with the machines?

Some says price doesn't lie. Well, may be not true but motorolla diodes are not expensive when we talk about high end systems. If I cannot hear the difference in the separate diodes, I will still have no reason to not use it, except the relative difficulty in assembling. As with snubber caps, I cannot hear the difference, but I have a reason to not use it. Because you should not add anything to the system unless you know what it can deliver.

[jneutron]

Originally posted by Sci
What about paralell connection of two bridges? Any problems there?

Erik

None...however, one of them will undoubtedly carry all the current. It will be difficult to balance the currents without some series resistors. The one with the lower vf dice will conduct and heat up, lowering it's vf even more..

One of sufficient capacity will work fine.

Cheers, John

[jackinnj]

Originally posted by jneutron


None...however, one of them will undoubtedly carry all the current. It will be difficult to balance the currents without some series resistors. The one with the lower vf dice will conduct and heat up, lowering it's vf even more..

One of sufficient capacity will work fine.

Cheers, John

OnSemi has a double-diode "in one" the MBR20100 -- which balances the current. It's in a TO-220 package like the MUR860.