Voltage conversion is a common part of modern circuits.

The easiest conversion technique involves stepping AC voltage up or down using transformers. In this technique two coils of wire are coupled to the same magnetic circuit, and the voltage experiences by each is a proportional to the number of windings in the coil.

Conversion from AC to DC involves two steps: the first is rectification, followed by filtering. In the rectification phase, diodes effectively clamp the negative output terminal to the point of lowest potential in the AC waveform. This results in a DC bias in the waveform as seen from the positive terminal. Riding on top of this DC bias is high-amplitude ripple voltage. The filtering phase uses active or passive components to remove and reduce this ripple. The success in removing the ripple is a critical measure in the design of AC-DC converters, and is referred to as voltage regulation.

Conversion from DC to AC typically involves charging and discharging capacitors and/or inductors which serve as an "ad-hoc" reserve of voltage and current for the power supply's load. The charge and discharge cycles vary in time exponentially, which is much different from the pure sinusoidal power supply required by many AC circuits. As a result, DC to AC conversion circuits also include wave-shaping and filtering components that use feed-back to approximate a voltage waveform that most closely approximates a sinusoidal signal. The success in delivering a perfectly clean sinusoidal AC voltage is a critical measure in the design of DC-AC converters and is referred to as spectral purity.

Finally DC-DC conversion uses an intermediate conversion to AC to alter the output voltage of the resulting signal. The process requires attention to losses at each phase of the conversion. The efficiency of delivering the output power without requiring extraneous power from the input DC supply is known as the efficiency of the DC-DC convertor.