Switch-mode power supply (SMPS) controller, SMPS system and power supply method for SMPS system

A switch-mode power supply system, comprising an AC voltage source, a rectifier connected to the AC voltage source, a bus capacitor connected to the rectifier, a bus DC voltage terminal connected to a common terminal to the bus capacitor and the rectifier and a switch-mode power supply controller, the switch-mode power supply controller comprising an output-voltage power supply unit, a built-in energy storage unit, a high-voltage power supply unit, a power sampling unit and a logic control unit, wherein the built-in energy storage unit and the logic control circuit are integrated in a single package, wherein:

• the output-voltage power supply unit has a terminal connected to an output voltage feedback terminal of the switch-mode power supply system and another terminal connected to a power input terminal of the built-in energy storage unit, and the output-voltage power supply unit is configured to charge the built-in energy storage unit using the output voltage from the switch-mode power supply system;
• and the built-in energy storage unit has a power output terminal connected to an operating voltage terminal of the logic control unit and is configured to provide operating voltage for the logic control unit to operate, the switch-mode power supply controller connected between the bus DC voltage terminal and an output voltage terminal of an switch-mode power supply,
• the high-voltage power supply unit has a terminal connected to the bus DC voltage terminal of the switch-mode power supply system, the high-voltage power supply unit has another terminal connected to the power input terminal of the built-in energy storage unit, and
• the logic control unit is configured to optimize a ratio of lengths of time respectively with the output-voltage power supply unit and the high-voltage power supply unit serving as a power supply based on measurements from the power sampling unit, the power sampling unit is configured to sample a current flowing through a power switch, and the output-voltage power supply unit is configured to charge the built-in energy storage unit under the control of the logic control unit over part or all of a load range for the switch-mode power supply system.

A power supply method for a switch-mode power supply system, comprising:

• providing a switch-mode power supply controller comprising a built-in energy storage unit, an output-voltage power supply unit, a high-voltage power supply unit, a power sampling unit and a logic control unit, wherein the built-in energy storage unit and the logic control circuit are integrated in a single package;
• and
• powering the built-in energy storage unit using an output voltage from the switch-mode power supply system by the output-voltage power supply unit such that the built-in energy storage unit provides an operating voltage for the switch-mode power supply controller, which ensures normal operation of the switch-mode power supply controller,
• wherein the logic control unit is configured to optimize a ratio of lengths of time respectively with the output-voltage power supply unit and the high-voltage power supply unit serving as a power supply based on measurements from the power sampling unit, the power sampling unit is configured to sample a current flowing through a power switch, and the output-voltage power supply unit is configured to charge the built-in energy storage unit under the control of the logic control unit over part or all of a load range for the switch-mode power supply system.