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Linear Power Supply based on HP/Agilent E3610A
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ZeTeX:
You might want to have a look here:
https://www.eevblog.com/forum/projects/lab-psu-design-ideaquestions/msg205205/#msg205205
timsu:
This circuit has the disadvantage of high power dissipation in the MOSFETs and an additional higher voltage to drive the gates is required.
I managed to save a few components compared to my last post with inverting the comparator input.
I will post an updatete schematic soon.

I looked for pass transistors and found these:
MJL 3281A
MJH 11022G
TIP142

What are your opinions on these?
sarepairman2:
keep in mind this was designed for mass production. you can do better  O0
Kleinstein:
The tip142 is good enough for 15 V 2 A, even without tap switching. So no need for the larger and more expensive ones.
With tap switching even a smaller version might be OK, but this won't save that much and a larger transistor could alow for a higher temperature or slightly smaller heat-sink.
The MJH 11022 looks a little slower - so I would not prefer that one.
The MJL 3281A is faster, but you need a good layout and likely quite some real life tests to really make use of it.

The FET tap switching from the old linked task is very similar to the one I suggested before, just for more taps and a regulator with emitter follower type output stage.  The main disadvantage is that the FETs at some times also have quite some power - so usually the FETs and the main output transistors should be mounted on the same heat-sink. Especially the 2 tap version I showed is really simple. For the relatively low voltage (e.g. < 20 V) the MOSFET sees it is not that difficult to find MOSFETs that can work in linear mode.

There is some extra effort to make the FETs switching and there can be small glitches when switching taps - so hysteresis is needed to avoid this (and possible instability) to happen just from ripple or load changes.
timsu:
Here another update:
- fixed some smaller bugs (wrong values)
- added tap switch
- opamp model selection
- beginning digital part
- simpler output disable

Todo:
- passive and transistor selection
- more protection
- digital circuit
- ...

Edit:
Should I add an RC Filter at the Output of the DAC?
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