Feedforward digital control unit for switched mode power supply and method thereof

摘要

To calculate a control signal for the duty cycle of a switched mode power supply (SMPS), a voltage feed forward compensator is integrated into a feedback unit. A control unit has an adder with a first input to receive a signal dependent upon an output voltage. A second input receives a signal from a feedback circuit, and an output outputs a signal comprising the sum of the signals applied to the inputs; another output outputs a control signal for controlling the duty cycle, the control signal is dependent upon the output signal from the adder; a voltage feed forward compensation signal generator calculates a compensation signal to adjust the control signal depending upon an input voltage of the SMPS; and a feedback circuit between the output of the adder and the second input of the adder calculates a compensated feedback signal and to feed the compensated feedback signal to the second input of the adder.

主权项

1. A digital control unit operable to calculate a digital control signal for controlling a duty cycle of a switched mode power supply, the digital control unit comprising:
an adder having at least a first input configured to receive a signal dependent upon an output voltage of the switched mode power supply, a second input configured to receive a signal from a feedback circuit, and an output configured to output an output signal comprising a sum of the signals applied to the inputs; a second output configured to output the digital control signal for controlling the duty cycle of the switched mode power supply, the digital control signal being dependent upon the output signal from the adder; a voltage feed forward compensation signal generator configured to calculate a compensation signal to adjust the digital control signal based on an input voltage of the switched mode power supply; and the feedback circuit positioned between the output of the adder and the second input of the adder and configured to calculate a compensated feedback signal by combining the compensation signal with a signal dependent upon the output of the adder and to feed the compensated feedback signal to the second input of the adder.