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Please comment: 10A 13.8V linear power supply

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duak:
Foldback limiting is a good idea to protect the regulator but is not appropriate if the load can draw a high current at low voltage during normal operation.  I see it as a way to use a smaller pass element and heatsink.

Some ideas to fix this are:
 - add some capacitance to the part of the current limiter that is sensitive to the voltage drop across the pass transistors.  This will allow the regulator to supply full current for short periods of time when the output voltage is below nominal.  I don't have time now to figure out how to do this with the existing circuit.
 - add a temperature sensitive element thermally connected to the heat sink that varies the limit current to limit dissipation in the pass transistors.  This is done in most monolithic regulators.

thinkfat:
PCBs are in and I've spend a day assembling and testing. The load sharing works fine, I get a roughly equal heat dissipation on all the pass transistors. The foldback circuit is working fine, I just have a slight dimensioning problem and it cuts off too early. As expected, bootstrapping is quite peculiar. I added a 1µF capacitor in parallel to R17 to help it start up. If the filter caps on the VCC rail are not discharged, it won't start up if VOUT is at 0V, too. That means, if the overcurrent protection trips, you need to switch off the power supply, wait for all the caps being discharged before you power it up again. So I'll add a bleed resistor of 500 Ohms or so to the capacitor bank. A 2W chip resistor in 2512 package should be fine here.

The 2k resistor in front of the 16V Zener diode is waaay to small. 70mW is seriously too much power for a SOT-23 to dissipate. Also, the 1k emitter resistor of Q6 is nonsense. It needn't be there at all.

Another point is the load regulation, it's much slower than in the simulation. I might experiment with the value of C9 and see if it improves.

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