Power failure prevention system with power management mechanism and method thereof

A power failure prevention method with a power management mechanism, which is applicable to a power failure prevention system, wherein the power failure prevention system includes a switch circuit, an energy storage circuit, a pre-charged circuit and a pre-charging control circuit, the switch circuit is connected to a first terminal of an inductor, the pre-charged circuit is connected to an input power source and a second terminal of the inductor and the pre-charging control circuit, the power failure prevention method comprises the following steps:

• (a) pre-charging the pre-charged circuit by the input power source;
• (b) obtaining a voltage of a node between the pre-charged circuit and the second terminal of the inductor, a voltage of the switch circuit or a voltage of the energy storage circuit as a pre-charged voltage by the pre-charging control circuit;
• (c) determining, by the pre-charging control circuit, whether or not the pre-charged voltage is higher than or equal to a reference voltage, wherein the reference voltage is lower than an input voltage provided by the input power source, in response to determining that the pre-charged voltage is not higher than or equal to the reference voltage, returning to step (a), in response to determining that the pre-charged voltage is higher than or equal to the reference voltage, performing next step (d);
• and
• (d) stopping pre-charging the pre-charged circuit and charging the energy storage circuit through the inductor and the switch circuit by the input power source.