Regulated Power Supplies have:
(1) Good output voltage regulation (see diagrams 1 & 2 ), so that:
— No-load voltage is not too high from rated voltage.
— Full-load voltage is not too low from rated voltage.
(2) Filtering of ac ripple so that output dc voltage is constant (see diagram 3)
Diagram 1 - variation of output dc voltage with load current.
Diagram 2 - Comparison of Regulated switching mode vs Unregulated dc supply.
Diagram 3 - Ripple in dc output before (gray) and after (red) regulation & filtering.
