The best way to put two 5V SMPS in parallel

Dear readers,

I’m designing a small 5V SMPS which I want to use in a 5V parallel configuration. I want to use ORing Diodes but these give me a drop of 0,2…0.4 Volt. So I came up with and better solution, but I don’t have experience with this one.

Below you see two buck converters. In SMPS[A] I have put the ORing diode in series with the output and in SMPS I have put the ORing diode before the FB resistor network. SMPS does not suffer from the 0.2…0.4 voltage drop. However in case the input voltage of B is zero the FB pin will have a voltage of around the FB voltage of 0.8V.
Assuming that both SMPS[A] and have input power the the combinations A-A A-B and B-B should work without a problem.
Assuming that SMPS[A] has input power SMPS has no power and is switched on after some time. The combinations A-A B-B will work but combination A-B I have my doubts about.
If B is powerless and has 0.8V at it’s feedback pin and ten starts up will that not generate trouble like latch up or some other issues I’m not aware of.
Now my question: does anyone have experience with this and can tell me if there are things I need to consider.

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For the ones who are interested,

I did some experiments with a circuit that I found on the Internet and it works quite well. The voltage window in which this switch is working is 150mV difference in output voltage of the two power supplies. Within this window, both power supplies supply a portion of the power. Outside this window only one of the two does, the one with the highest voltage. The picture show the edge of the window in which around 12mA is supplied by the left power supply. With the right voltage at 5.16V the left current is practically zero.

I’m designing a small 5V SMPS which I want to use in a 5V parallel configuration

A much better idea is to use one SMPS module that can comfortably provide the required current.