voltage and current regulation

[Dimbulb]

several terms current limiter, current limiting
regulator and current source regulation are related.

If I understand correctly Finding an appropriate
semiconductor scheme involves thermal charecteristics so the device being powered
can have ultra stability. This is the amount of dissipation required is related to the amount current needed. The device when inside a body would have stable temperature.

Other than pure current is the noise that gets into everthing, using an lm431 may give cleaner current hopefully minimize the noise. A good data sheet should give an example of this super zener in a current control scenario.