Power system having a power saving mechanism

A power system comprising:

• a voltage regulator having a voltage input port for receiving a first voltage and a voltage output port for outputting a second voltage;
• a switching signal generation unit, electrically connected to the voltage output port or the voltage input port of the voltage regulator, for generating a switching signal according to an indication signal;
• a feedback processing circuit, electrically connected to the voltage input port of the voltage regulator and the switching signal generation unit, for generating a feedback signal according to the first voltage and the switching signal;
• and
• a power input module comprising:
• a transformer having a primary winding for receiving an input voltage, a secondary winding, and an auxiliary winding;
• a rectification unit, electrically connected between the secondary winding and the voltage input port of the voltage regulator, for generating the first voltage;
• a first switch, electrically connected to the primary winding in series, for controlling a current flowing through the primary winding;
• and
• a switch control unit, electrically connected to the auxiliary winding and the first switch, for generating a control signal to control the first switch according to the feedback signal.

A power system comprising:

• a voltage regulator having a voltage input port for receiving a first voltage, a voltage output port for outputting a second voltage, and an enable port;
• a switching signal generation unit, electrically connected to the voltage output port or the voltage input port of the voltage regulator, for generating the first switching signal to the enable port, a second switching signal and a third switching signal according to an indication signal;
• a feedback processing circuit, electrically connected to the voltage input port of the voltage regulator and the switching signal generation unit, for generating a feedback signal according to the first voltage and the second switching signal;
• a first switch, electrically connected between the voltage input port and the voltage output port of the voltage regulator, for controlling an electrical connection between the voltage input port and the voltage output port of the voltage regulator according to the third switching signal;
• and
• a power input module comprising:
• a transformer having a primary winding for receiving an input voltage, a secondary winding, and an auxiliary winding;
• a rectification unit, electrically connected between the secondary winding and the voltage input port of the voltage regulator, for generating the first voltage;
• a second switch, electrically connected to the primary winding in series, for controlling a current flowing through the primary winding;
• and
• a switch control unit, electrically connected to the auxiliary winding and the second switch, for generating a control signal to control the second switch according to the feedback signal.