35+35 800w smps

[thetube0a3]

I'm looking into building a 200+W x 2 chipamp and want to use a switching supply this time around.

What I don't know is if there are any bipolar SMPS on the market that meet my requirements, so far I have not been able to find a bipolar SMPS period.

If these cannot be bought off the shelf, how difficult is it to build one and are all of the parts available off the shelf?

I would need 30 to 35volt rails and a total power of around 800 watts give or take.

Any advice is welcome.

[luka]

well you could buy 2, that have single output, don't think you will get 35v out of them (no such modul). Building one yourself, its easy for me, but could be very hard for you, if you didn't do anything like that before.
Also you don't need 800w, coz those amps will draw this power only as peak, not average, which meas you can get away with smaller powers

[savu]

and also ...

why do you need it to have bipolar switchees insted of mosfets ?

regards,
savu

[star882]

You might be able to use two modified PC power supplies in series, each one tweaked up to 15v. Or get a 48v telecom supply and tweak it down, but going all the way down to 35v is asking a little much. Or you might be able to use a 48v supply as is and redesign your amplifier. TI's TAS5630 is designed to run on a 48v rail.

There's little reason to use bipolar for power supplies now. They were traditionally used at high voltages to overcome limitations of MOSFETs, but IGBTs are now the transistor of choice for high voltage, high current applications.

[thetube0a3]

I'm sorry perhaps I misspoke. I did not mean bipolar transistors I meant bipolar rails, as in +35 and -35 rails.

[star882]

It's better to use a single rail design, like the TAS5630, unless you really need a ground referenced output for some reason.

[thetube0a3]

Star882, its funny you should say that. I was originally going to use this to drive a chipamp build of mine (lm3886) but recently decided to go with a class D design this time and I was looking at the TAS5630.

I also found many companies offer SMPS in this size. anything from 800-1500W at 48-60V is easily available.

I was thinking perhaps using two TAS5630's in a single chassis.

How do the TAS5630's sound? good enough to use with full range speakers? or would you recommend using it only for low frequency?

[star882]

I haven't used the TAS5630 in my own design, but a demo board I saw at an IEEE event performed extremely well for the full audio spectrum.