A voltage regulator comprising: at least one power switch (12, 14) adapted to convey power between respective input and output terminals of said voltage regulator; and a digital controller adapted to control operation of said at least one power switch (12, 14) responsive to an output of said voltage regulator, said digital controller comprising: a first digital control loop including a first analog-to-digital converter providing a first digital measurement of said voltage regulator output, a digital filter (142, 144, 146, 148) providing a digital control output based on a first digital error signal and a second digital error signal, and a digital pulse width modulator providing a control signal to said at least one power switch (12, 14) based on said digital control output; and a second digital control loop including a second analog-to-digital converter providing a second digital measurement of said voltage regulator output, said second analog-to-digital converter having greater resolution than said first analog-to-digital converter, said second digital control loop providing a digital reference value based on a desired output voltage setpoint, said second digital control loop providing said time varying portion of the digital reference value based on a difference between said second digital measurement and said output voltage setpoint; characterized in that the first digital error signal comprises a difference between the first digital measurement and the digital reference value, and the second digital error signal comprises a sum of the first digital error signal and a time varying portion of the digital reference value, wherein said digital filter comprises proportional, integral and derivative arithmetic units (144, 146, 142), wherein said first digital error signal is provided to said proportional and derivative arithmetic units (144, 142), and wherein said second digital error signal is provided to said integral arithmetic unit. at least one power switch (12, 14) adapted to convey power between respective input and output terminals of said voltage regulator; and a digital controller adapted to control operation of said at least one power switch (12, 14) responsive to an output of said voltage regulator, said digital controller comprising: a first digital control loop including a first analog-to-digital converter providing a first digital measurement of said voltage regulator output, a digital filter (142, 144, 146, 148) providing a digital control output based on a first digital error signal and a second digital error signal, and a digital pulse width modulator providing a control signal to said at least one power switch (12, 14) based on said digital control output; and a second digital control loop including a second analog-to-digital converter providing a second digital measurement of said voltage regulator output, said second analog-to-digital converter having greater resolution than said first analog-to-digital converter, said second digital control loop providing a digital reference value based on a desired output voltage setpoint, said second digital control loop providing said time varying portion of the digital reference value based on a difference between said second digital measurement and said output voltage setpoint; a first digital control loop including a first analog-to-digital converter providing a first digital measurement of said voltage regulator output, a digital filter (142, 144, 146, 148) providing a digital control output based on a first digital error signal and a second digital error signal, and a digital pulse width modulator providing a control signal to said at least one power switch (12, 14) based on said digital control output; and a second digital control loop including a second analog-to-digital converter providing a second digital measurement of said voltage regulator output, said second analog-to-digital converter having greater resolution than said first analog-to-digital converter, said second digital control loop providing a digital reference value based on a desired output voltage setpoint, said second digital control loop providing said time varying portion of the digital reference value based on a difference between said second digital measurement and said output voltage setpoint;