Feedback control system and feedback control method

1 . A feedback control system, comprising:

a driver chip comprising a first output terminal and a first input terminal, wherein the first output terminal is to output a first detection voltage; and

a power chip comprising a second input terminal and a second output terminal, wherein the second input terminal is directly connected to the first output terminal, and the second output terminal is coupled to the first input terminal, wherein the power chip generates a driving voltage according to the first detection voltage and outputs the driving voltage to the first input terminal,

wherein the driver chip comprises:

at least one application circuit;

at least one control circuit coupled between the at least one application circuit and the first output terminal to generate the first detection voltage according to a second detection voltage or a third detection voltage from the at least one application circuit; and

at least one resistor selecting circuit coupled between the at least one control circuit and the first output terminal to output the first detection voltage according to the second detection voltage or the third detection voltage,

wherein the at least one application circuit comprises a first functional circuit and a second functional circuit, the second detection voltage is a first input voltage of the first functional circuit, and the third detection voltage is a second input voltage of the second functional circuit.

2 . The feedback control system of claim 1 , wherein the at least one control circuit comprises:

a plurality of switches coupled between the at least one application circuit and the first output terminal to receive the second detection voltage and the third detection voltage respectively.

3 . The feedback control system of claim 1 , wherein the power chip further comprises:

a voltage converter circuit coupled to the at least one resistor selecting circuit to adjust the driving voltage according to the first detection voltage.

4 . The feedback control system of claim 1 , wherein the at least one resistor selecting circuit comprises:

a feedback resistor string coupled to the at least one control circuit to receive a control voltage which is generated by the at least one control circuit according to the second detection voltage or the third detection voltage and to generate a plurality of divided voltages according to the control voltage; and

a selector circuit coupled to the feedback resistor string to receive the plurality of divided voltages and to generate the first detection voltage at the first output terminal according to the plurality of divided voltages.

5 . The feedback control system of claim 4 , wherein the feedback resistor string is coupled between the control voltage and a ground terminal.

6 . The feedback control system of claim 4 , wherein the feedback resistor string is coupled between a reference voltage and the control voltage.

7 . The feedback control system of claim 4 , wherein the at least one resistor selecting circuit further comprises:

a buffer coupled between the selector circuit and the first output terminal.

8 . The feedback control system of claim 1 , wherein when the driver chip is in a light-load condition, the driving voltage has a first value,

wherein when the driver chip is in a heavy-load condition, the driving voltage has a second value,

wherein the first value is less than the second value.

9 . The feedback control system of claim 1 , wherein the at least one application circuit comprises:

a plurality of application circuits, wherein each of the plurality of application circuits is to output the first detection voltage to the power chip.

10 . The feedback control system of claim 9 , wherein the at least one control circuit comprises:

a plurality of control circuits, wherein each of the plurality of control circuits is to receive the second detection voltage or the third detection voltage from a corresponding one of the plurality of application circuits to output the first detection voltage.

11 . The feedback control system of claim 10 , wherein the at least one resistor selecting circuit comprises:

a plurality of resistor selecting circuits, wherein each of the plurality of resistor selecting circuits is coupled between a corresponding one of the plurality of control circuits and a corresponding one of a plurality of the first input terminals.

12 . A feedback control method, comprising:

outputting, by a first output terminal of a driver chip, a first detection voltage, wherein the driver chip further comprises a first input terminal;

receiving, by a second input terminal of a power chip, the first detection voltage, wherein the second input terminal of the power chip is directly connected to the first output terminal of the driver chip, and a second output terminal of the power chip is coupled to the first input terminal of the driver chip;

generating, by the power chip, a driving voltage according to the first detection voltage; and

outputting, by the power chip, the driving voltage to the first input terminal of the driver chip,

wherein the driver chip comprises:

an application circuit;

a control circuit coupled between the application circuit and the first output terminal to generate the first detection voltage according to a second detection voltage or a third detection voltage from the application circuit; and

a resistor selecting circuit coupled between the control circuit and the first output terminal to output the first detection voltage according to the second detection voltage or the third detection voltage,

wherein the application circuit comprises a first functional circuit and a second functional circuit, the second detection voltage is a first input voltage of the first functional circuit, and the third detection voltage is a second input voltage of the second functional circuit.

13 . The feedback control method of claim 12 , wherein the feedback control method further comprises:

receiving, by a plurality of switches in the control circuit, the second detection voltage and the third detection voltage respectively.