Patent ID: 8599052

Claim:
A controller for use in a power supply, the controller comprising: a variable oscillator that generates a switching signal having an on-time and a switching period to control a first switch to regulate an output of the power supply; and a digital-to-analog converter (DAC) coupled to the variable oscillator to provide the variable oscillator with a first analog signal and a second analog signal, wherein the on-time of the switching signal generated by the variable oscillator is responsive to the first analog signal and wherein the switching period is responsive to the second analog signal, the DAC comprising: a current source; and a second switch coupled to the current source and configured to couple the current source to provide current to the first analog signal in response to a binary digit received by the DAC, wherein the switch is further configured to couple the current source to provide current to the second analog signal in response to a complement of the binary digit.