I'm doodling with a future circuit. The application (Commodore 64) expects 5VDC (which I will provide with a pass-through) and 9VAC 50Hz. I do not have any working circuit or a schematic, because the circuit does not yet exist other than as an idea, but I have this very crude block diagram:
The circuit is fed by an external power supply, with 5V@10A and 12V@10A. I can use whichever I want. Even both. Since I want 9VAC in the final step (~13V û), I want some headroom for the H-bridge. So I pick 18V. That's what I want the DC/DC to achieve for me.
I think I need isolated DC/DC, but I'm not sure. What I'm sure about is that the 9VAC needs to swing around 0V, so no DC-components or offsets on it. With isolated DC/DC, I'm hoping (yes, because this area is completely out of my league) that the 9VAC will look like any 9VAC wallwart would produce. At least, that's my goal.
The 9VAC is supposed to be able to deliver 750mA continuously, so I will design for 1A. Bonus is if I can manage to double it.
There's a lot of new things here for me, so I need to break things down to make them graspable. At this point, I will put the PIC/Bridge/LC aside for a while and focus on the DC/DC.
I know MAX1523 will work here, but it's way too expensive. Will LM2735 (datasheet) be of any use for my design?
What part(s) in my block diagram are responsible for the maximum amps at the outputs? The DC/DC, the H-bridge, or both?
Flyback topologies seem to use a transformer for isolation. Datasheet for MAX1523 suggests using a dual inductor with ferrite core (to save space). If this sort of isolation is used, will the 9VAC output be of the type I want (no DC-offets, etc)?