Comparing P3A Schematics

[cumbb]

Simply try;-)

 

[rafaelct]

Hello, I would like to ask if it would be possible to power this circuit (P3A) with +-45V DC? Thank you

 

[brian92fs]

I won't try that with only one output pair. You could push it to 42V if you are driving 8R loads but 45V is risky

 

[rafaelct]

And can you help me with a schematic with Sc5200 and 2SA1943 that can work with that voltage? Thank you

 

[brian92fs]

You'll need two pairs of output devices to support 45V rails. It's untested, but if you go this route you'll probably want to entertain a few changes.

1. The output devices should have emitter resistors to allow for current sharing. 0R1 is probably fine for this.
2. Driver collector resistors R11/R12 can be dropped from 220R to 100R to supply the additional current needed to drive two devices.
3. The OPS resistors R13/R14 will need to have a higher power rating. They're spec'd at 3W to 5W with one pair. For 2 pairs and 8R loads, you'll want 5W at a minimum. If you plan on driving 4R loads, You'll want at least 10W for these, maybe larger.

If you look at Douglas Self's load invariant blameless, you'll see that the it's output stage looks a lot like this.

I'm not aware of any P3A PCB clones that accommodate this. Do you plan to design your own boards?

 

[rafaelct]

My idea is to use a single 5200 - 1943 output pair because I don't need that much power. I would like to know if the accompanying schematics are known and if they could work. (In all cases with a single pair 5200-1943). I would make the corresponding PCB. Thank you

 

[brian92fs]

The designs you are proposing are not CFP / P3A topologies. My response was assuming you were talking about a P3A based amp. As this is a P3A thread, I'd suggest starting a new thread . I think you'll get more responses as this is a bit off topic.

 

[rafaelct]

Eso haré, muchas gracias por su atención.