What is a key characteristic of power supply circuits?

A key characteristic of power supply circuits is their ability to keep the output voltage constant as load current changes. This stability is essential for electronic devices to function correctly, as fluctuations in voltage can lead to erratic behavior or damage to sensitive components.

Power supplies are designed to minimize variations in output voltage caused by changes in the load, ensuring that the devices supplied with power receive a consistent level of voltage regardless of how much current they are drawing at any given moment. This is achieved through various regulation techniques that monitor the output and adjust the input or the conversion process to retain the desired output voltage.

In contrast, varying output voltage with load changes can lead to performance issues, and increasing input voltage or converting DC to AC electricity are functions that may occur in specific contexts but do not define the fundamental operation of power supply circuits.