[sdiy] Which opamp pins wiring is best for CV out ?? A or B ??

[Richie Burnett]

Circuit A does not compensate for the DC voltage drop across the 
current-limit resistor because it is outside the feedback loop.  However, 
it's high frequency stability is excellent because the op-amp output is 
decoupled from any load capacitance by the resistor.

Circuit B compensates for the DC voltage drop across the current-limiting 
resistor due to load current.  The only problem with it is that any load 
capacitance, e.g. capacitance from driving a long cable degrades the phase 
margin of the op-amp and is likely to make it oscillate.

The best solution is one that combines the advantages of both schematics.

-Richie Burnett,