Op Amp SOA and output current

[Jwillis]

I hate to bring this circuit up yet again.But I've been working on the circuit of the infamous 0-30v 0-3A Power supply with some modifications.
I'm using the OPA445 Op Amp and so far have made successful progress in the Voltage and Current control. So far I have 0-32 volts and 0- 2.7 Amps with a 24 volt AC source .I'm not concerned about temperature drift of the zeners I've used at this time.I eventually want to increase the voltage to a 50V output so other changes will be required for better regulation.
I want to jack up the amperage but I also don't want to overwork the op amps. So when determining the Vs (Voltage source) is the the additive voltage to both positive and negative Supply? By this I men, theirs  33.5 volts to the positive rail and - 16.5 volts to the negative rail so the total voltage would be 50 Volts? And the Vo (Voltage out) is 0-32Volts. So I would read the  current SOA  (Vs - Vo)  As 50 volts maximum which would give me around 1 mA Safely at the out put?Would that be correct?

https://www.ti.com/lit/ds/symlink/opa445.pdf

[magic]

Yes, it's correct, at ambient temperature of 120°C, whatever that means. At lower temperature more is permissible.
Also, the datasheet is wrong. It's not |Vo|-|Vs| but |Vo-Vs|, where Vs is the supply rail which supplies current to the output. So V+ for sourcing and V- for sinking. It can make a difference if supplies aren't symmetric or if you drive a load referenced to the opposite supply rail rather than ground.

Wait, no. It's not entirely correct. It's only correct if supply-output differential is at its maximum. If you drive positive current at 10V below positive supply, you only are concerned about current limit for |Vo-Vs|=10V. If you drive negative current at 10V below positive supply, then |Vo-Vs|=40V.

[Zero999]

Is there already a thread on this? If so, it would have been better to simply continue it, rather than creating a new one, so we can see the schematic. Please post a link., otherwise, please post the schematic here.

You shouldn't worry about the op-amp, which probably won't have to output much current. The output transistors are where most of the power dissipation will be. For 50V, a transformer tap switching arrangement should be used, to minimise the power dissipation in the output transistors.

[Jwillis]

Is there already a thread on this? If so, it would have been better to simply continue it, rather than creating a new one, so we can see the schematic. Please post a link., otherwise, please post the schematic here.

You shouldn't worry about the op-amp, which probably won't have to output much current. The output transistors are where most of the power dissipation will be. For 50V, a transformer tap switching arrangement should be used, to minimise the power dissipation in the output transistors.

Thanks for the reply. I'm relatively new to op amps and I was simply asking if I as understanding the Data sheet correctly and saw no point in presenting a schematic at this time . This project has an on going evolution which includes transformer changes.I imagine by the time I'm finished it won't look anything  like the original schematic.

But i do appreciate the help.