Static input variation

In power circuits and similar contexts, when the load current is under rated conditions and the input voltage is varied gradually within the specified range, this refers to the fluctuation of the output voltage. It is one of the indicators that show the stability of the power circuit against input variations. The smaller the static input variation, the higher the stability against long-term gradual fluctuations in input voltage. This is useful, for example, when the commercial power supply used as the input changes gradually over the course of a day due to the balance of supply and demand, as it helps to estimate the stability of the output voltage.