How to Connect a Voltage Regulator in a Circuit The regulator regulates this voltage down to 5 volts. After it comes out of the regulator, the other capacitor, the 0 ceramic, cleans up any high-frequency or ac noise that may come out, again to produce a clean DC signal. voltage regulator – Circuit Wiring Diagrams A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. Depending on the design, it may be used to regulate one or more AC or DC voltages. Below picture shows a Chrysler | Force Voltage Regulator Wire Harness.