DC/DC Topologies needed

[Bakmeel]

Dear members,

My BIG DC/DC converter is making good progress. I've run 1.8kW clean lately, and 3.3kW peak in a bidirectional Buck/Boost topology.

Now I all I need is some good options for the local Auxiliary PS. I need two functions:

* 8-9V in to 13V and 5V. 5V needs regulation. the 13V line is not that critical. I estimate around 1A consumption on both voltages.

* 400V in to 8-9V. Regulation is not critical. Isolation is not nescessary but feels better 🙂 Output draws 3A max.

Any suggestions?
Thanx

 

[poobah]

Check out the SI9120 family (Siliconix). These have a nifty built in DMOS fet for bootstrapping directly from 600 Volts. Also look at Supertex as the they have 2nd source for the SI parts but also discrete DMOS.

You are on the hairy edge of practicality for a flyback... you'll need a sizeable inductor. But it is a fast build. Choose which secondary to take feedback from carefully and let the remaining sec's cross regulate.

😉

 

[Bakmeel]

Thanx for the reply poobah,

I found some interesting converters...

9V to 14V will be a boost with integrated fet: Monolithic Power Systems has MPS1517 and MPS1527. at 1.3Mhz I can reduce the inductor to a mere 10uH 🙂

400V to 9V will be a flyback based on TL2843. I recalculated the thing and found that I need 6A worst case, so that's going to eat more hardware.

More to post soon 🙂