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Sziklai pair for voltage regulation?

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ElectronSurf:
While studying different lab power supply schematics, I noticed that every one of them used a darlington configuration.

In this article the author mentions that the Sziklai pair has lower voltage drop, better thermal stability and better linearity compared to darlington pair.
https://sound-au.com/articles/cmpd-vs-darl.htm

I know it's an old discussion comparing this two configurations but the discussion was usually for audio related circuits.

Is the Sziklai pair performs better than darlington pair for voltage regulation in lab PSUs and if yes why it's not used widely?

langwadt:
a Sziklai pair with a big NPN acts like a PNP, with that comes all the stability issues of an LDO

ElectronSurf:

--- Quote from: langwadt on April 21, 2020, 02:27:08 pm ---a Sziklai pair with a big NPN acts like a PNP, with that comes all the stability issues of an LDO

--- End quote ---

How about with an NPN driver and big PNP?

fcb:
The output pass transistor arrangement of a typical 'lab supply' is within a main feedback loop - so the Sziklai benefit of less variable voltage drop, thermals, linearity is largely irrelevant.

The effective conversion from NPN to PNP could be useful if you want to use the same power devices in a split-rail supply.  Also the single Vbe drop would help if you are designing a tracking post-regulator.

ElectronSurf:

--- Quote from: fcb on April 21, 2020, 02:33:18 pm ---The output pass transistor arrangement of a typical 'lab supply' is within a main feedback loop - so the Sziklai benefit of less variable voltage drop, thermals, linearity is largely irrelevant.

The effective conversion from NPN to PNP could be useful if you want to use the same power devices in a split-rail supply.  Also the single Vbe drop would help if you are designing a tracking post-regulator.

--- End quote ---

Less voltage drop and better thermal characteristics and still designers choose to use darlington configuration, why?

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