Patent ID: 8836167

Claim:
A power redundant system, comprising: N first voltage generators, for providing N different voltages; M second voltage generators, for providing M different voltages, wherein a voltage of the i-th first voltage generator is the same as that of the j-th second voltage generator, the j-th second voltage generator operates and supplies the voltage when the j-th second voltage generator receives a power enable signal, the j-th second voltage generator outputs a power good signal when supplying the voltage normally, N and M are positive integers greater than 1, i is a natural number and is less than or equal to N, and j is a natural number and is less than or equal to M; a switch unit, coupled to the i-th first voltage generator and the j-th second voltage generator, and for receiving a power control signal, to select one of two outputs of the i-th first voltage generator and the j-th second voltage generator to be connected to an output of the switch unit; and a control unit, coupled to the switch unit and the j-th second voltage generator, wherein the control unit generates a power enable signal according to a power supply signal, when the power good signal is enabled, the control unit enables the power control signal to control the switch unit so that the output of the switch unit is connected to the output of the j-th second voltage generator, and when the power supply signal is enabled and the power good signal is disabled, the control unit disables the power control signal to control the switch unit so that the output of the switch unit is connected to the output of the i-th first voltage generator.