Control method and control circuit of a multi-phase converter

1. A method of controlling a multi-phase converter, the method comprising:

a) generating a plurality of sampling signals corresponding to a plurality of channels of the multi-phase converter, wherein each sampling signal represents an inductor current of a corresponding channel;

b) generating a plurality of error signals corresponding to the plurality of channels, wherein each of the error signals represents an error between the inductor current of the corresponding channel and a reference current;

c) generating, by a modified circuit, a plurality of modified sampling signals according to the sampling signals regulated in accordance with the corresponding error signal, wherein each of the modified sampling signals comprises a sum of the corresponding sampling signal and the corresponding error signal; and

d) balancing, by a control circuit, the inductor currents of the channels according to the plurality of modified sampling signals by generating an error compensation signal that represents a difference between an output feedback signal and an output reference signal of the multi-phase converter, and generating a plurality of switch drive signals by comparing the error compensation signal and each of the modified sampling signals to control a switching state of a power switch of each of the channels.

2. The method of claim 1 , wherein the generating the plurality of error signals comprises:

a) generating a plurality of first average signals corresponding to the plurality of channels of the multi-phase converter, wherein each of the plurality of first average signals represents an average of the inductor current of the corresponding channel; and

b) generating the corresponding error signal according to a difference between the first average signal and a reference characterization signal of the reference current.

3. The method of claim 2 , further comprising generating a second average signal representing an average of the plurality of first average signals, wherein the second average signal is set as the reference characterization signal.

4. A control circuit of a multi-phase converter, the control circuit comprising:

a) an inductor current sampling circuit configured to generate a plurality of sampling signals corresponding to a plurality of channels of the multi-phase converter, wherein each of the sampling signals represents an inductor current of a corresponding channel;

b) an error circuit configured to generate a plurality of error signals corresponding to the plurality of channels, wherein each of the error signals represents an error between the inductor current of the corresponding channel and a reference current; and

c) a modified circuit configured to regulate the sampling signals of the corresponding channels according to the plurality of error signals to generate a plurality of modified sampling signals, wherein the control circuit balances the inductor currents between the plurality of channels according to the plurality of modified sampling signals, and wherein each of the modified sampling signals comprises a sum of the corresponding sampling signal and the corresponding error signal.

5. The control circuit of claim 4 , wherein the error circuit comprises:

a) a first average circuit configured to generate a plurality of first average signals representing the plurality of channels of the multi-phase converter, wherein each of the plurality of first average signals represents an average of the inductor current of the corresponding channel; and

b) a difference circuit configured to generate the corresponding error signal according to a difference between the first average signal and a reference characterization signal of the reference current.

6. The control circuit of claim 4 , wherein the error circuit further comprises a second average circuit configured to generate a second average signal representing an average of a plurality of first average signals that is configured as the reference characterization signal.

7. The control circuit of claim 4 , wherein the modified sampling signal is increased when the error signal is greater than zero, and the modified sampling signal is decreased when the error signal is less than zero.

8. The control circuit of claim 4 , further comprising:

a) an error compensation circuit configured to generate an error compensation signal representing an output feedback signal and an output reference signal of the multi-phase converter;

b) a comparison circuit configured to compare the error compensation signal and each of the modified sampling signals to output a plurality of comparison signals; and

c) a switch drive signal generating circuit configured to generate a plurality of switch drive signals according to each of the comparison signals to control a switching state of a power switch of each of the channels, thereby balancing the inductor currents between each of the channels.

9. A control circuit of a multi-phase converter, the control circuit comprising:

a) an inductor current sampling circuit configured to generate a plurality of sampling signals corresponding to a plurality of channels of the multi-phase converter, wherein each of the sampling signals represents an inductor current of a corresponding channel;

b) an error circuit configured to generate a plurality of error signals corresponding to the plurality of channels, wherein each of the error signals represents an error between the inductor current of the corresponding channel and a reference current;

c) a modified circuit configured to regulate the sampling signals of the corresponding channels according to the plurality of error signals to generate a plurality of modified sampling signals, wherein the control circuit balances the inductor currents between the plurality of channels according to the plurality of modified sampling signals, and wherein each of the modified sampling signals comprises a sum of the corresponding sampling signal and the corresponding error signal;

d) an error compensation circuit configured to generate an error compensation signal representing an output feedback signal and an output reference signal of the multi-phase converter;

e) a comparison circuit configured to compare the error compensation signal and each of the modified sampling signals to output a plurality of comparison signals; and

f) a switch drive signal generating circuit configured to generate a plurality of switch drive signals according to each of the comparison signals to control a switching state of a power switch of each of the channels, thereby balancing the inductor currents between each of the channels.

10. The control circuit of claim 9 , wherein the error circuit comprises:

a) a first average circuit configured to generate a plurality of first average signals representing the plurality of channels of the multi-phase converter, wherein each of the plurality of first signals represents an average of the inductor current of the corresponding channel; and

b) a difference circuit configured to generate the corresponding error signal according to a difference between the first average signal and a reference characterization signal of the reference current.

11. The control circuit of claim 9 , wherein the error circuit further comprises a second average circuit configured to generate a second average signal representing an average of a plurality of first average signals, so as to be set as a reference characterization signal.