Multiphase switching converter with stackable controllers
A controller for a multiphase switching converter has a feedback pin, a reference pin, and a plurality of switching control pins. When the controller is a master controller, the reference pin provides a reference output signal based on a plurality of currents flowing through a plurality of switching circuits. When the controller is a slave controller, the feedback pin receives the reference output signal from the master controller, and the slave controller provides the plurality of switching control signals based on the plurality of currents flowing through the plurality of switching circuits, the reference output signal, and a feedback signal representative of an output voltage of the multiphase switching converter.
1 . A controller for a multiphase switching converter with a plurality of switching circuits, comprising:
a first feedback pin, configured to receive a feedback signal representative of an output voltage of the multiphase switching converter;
a second feedback pin, configured to receive a reference output signal representing a current flowing through another multiphase switching converter;
a plurality of switching control pins, configured to provide a plurality of switching control signals based on the feedback signal and a current adjusting signal to control the plurality of switching circuits; and
a plurality of current sense pins, configured to receive a plurality of current sense signals representative of the plurality of currents flowing through the plurality of switching circuits; wherein
the controller is configured to provide the current adjusting signal based on the reference output signal and a plurality of currents flowing through the plurality of switching circuits; and wherein
the controller is configured to balance the plurality of currents flowing through the plurality of switching circuits with the current flowing through the another multiphase switching converter based on the plurality of current sense signals and the reference output signal.
2 . The controller of claim 1 , wherein the controller further comprising:
a current adjusting circuit, configured to provide the current adjusting signal; and
a switching control circuit, configured to generate the plurality of switching control signals to turn on the plurality of switching circuits in sequence based on the current adjusting signal and the feedback signal.
3 . The controller of claim 2 , wherein when a sum of the feedback signal and the current adjusting signal is less than a voltage reference signal, then one of the plurality of switching circuits is turned on.
4 . The controller of claim 1 , wherein when an ON-time period of one of the plurality of switching circuits reaches a time threshold, then the one of the plurality of switching circuits is turned off, the time threshold is adjusted based on a current flowing through the one of the plurality of switching circuits.
5 . A control method for a multiphase switching converter with a plurality of switching circuits, comprising:
receiving a feedback signal representative of an output voltage of the multiphase switching converter;
receiving a reference output signal representing a current flowing through another multiphase switching converter;
providing a plurality of switching control signals to control the plurality of switching circuits;
providing a current adjusting signal based on the reference output signal and a sum of a plurality of currents flowing through the plurality of switching circuits; and
turning on the plurality of switching circuits in sequence based on the current adjusting signal and the feedback signal;
receiving a plurality of current sense signals representative of the plurality of currents flowing through the plurality of switching circuits; and
balancing the plurality of currents flowing through the plurality of switching circuits with the current flowing through the another multiphase switching converter based on the plurality of current sense signals and the reference output signal.
6 . The control method of claim 5 , wherein when a sum of the feedback signal and the current adjusting signal is less than a voltage reference signal, then one of the plurality of switching circuits is turned on.
7 . The control method of claim 5 , further comprising:
adjusting a time threshold based on a current flowing through one of the plurality of switching circuits; and
turning off the one of the plurality of switching circuits when an ON-time period of the one of the plurality of switching circuits reaches the time threshold.
8 . A controller for a multiphase switching converter with a plurality of switching circuits, comprising:
a first feedback pin, configured to receive a feedback signal representative of an output voltage of the multiphase switching converter;
a second feedback pin, configured to receive a reference output signal representing a current flowing through another multiphase switching converter;
a plurality of switching control pins, configured to provide a plurality of switching control signals based on the feedback signal, the reference output signal and a plurality of currents flowing through the plurality of switching circuits, to control the plurality of switching circuits; and
a current adjusting circuit configured to provide a current adjusting signal to balance the plurality of currents flowing through the plurality of switching circuits with the current flowing through the another multiphase switching converter based on the reference output signal and a sum of the plurality of currents flowing through the plurality of switching circuits.
9 . The controller of claim 8 , wherein when a sum of the feedback signal and the current adjusting signal is less than a voltage reference signal, then at least one of the plurality of switching circuits is turned on.
10 . The controller of claim 8 , wherein the controller is configured to adjust the plurality of currents flowing through the plurality of switching circuits in response to the current flowing through the another multiphase switching converter.