Switching power supply control circuit and switching power supply using same

A control circuit that controls a switching power supply including a plurality of switching circuit blocks and a plurality of output reactors connected in parallel to an associated one of the switching circuit blocks, comprising:

• a calculator that calculates a difference between reactor currents flowing through the plurality of output reactors and an average value of the reactor currents flowing through the plurality of output reactors, respectively;
• a control voltage generator that generates control voltages corresponding to each of the plurality of switching circuit blocks using delta-sigma modulation and based on the calculated difference and an output voltage of the switching power supply;
• a plurality of comparators that compare the control voltages against a reference voltage;
• and
• a plurality of latch circuits that latch the outputs of the comparators in response to a clock signal.

A switching power supply comprising:

• a plurality of switching circuit blocks;
• a plurality of output reactors connected in parallel to an associated one of the switching circuit blocks;
• a control circuit that controls a operation of the plurality of switching circuit blocks in accordance with a delta-sigma modulation scheme;
• wherein:
• the control circuit comprises:
• a voltage control loop that stabilizes an output voltage of the switching power supply;
• and
• a current control loop that balances the reactor currents flowing through each of the plurality of output reactors without interfering the voltage control loop.

A switching power supply comprising:

• a plurality of switching circuit blocks;
• a plurality of output reactors connected in parallel to an associated one of the switching circuit blocks;
• a control circuit that uses delta-sigma modulation to control operation of the plurality of switching circuit blocks, wherein:
• the control circuit comprises:
• a calculator that calculates a difference between reactor currents flowing through the plurality of output reactors and an average value of the reactor currents flowing through the plurality of output reactors, respectively;
• a control voltage generator that generates control voltages corresponding to each of the plurality of switching circuit blocks based on the calculated difference and an output voltage of the switching power supply;
• a plurality of comparators that compare the control voltages against a reference voltage;
• and
• a plurality of latch circuits that latch the outputs of the comparators in response to a clock signal.