Patent ID: 8810227

Claim:
A method of operating a switched-mode power supply, the method comprising: producing an error signal based on a difference between an output voltage of the power supply and a reference voltage; producing a clock signal having a clock frequency based on the error signal, the clock frequency being proportional to the error signal up to maximum frequency; sensing a current in the switched-mode power supply to produce a sensed current signal; summing the error signal with the sensed current signal to produce a first signal; comparing the first signal with a first threshold, wherein summing the error signal comprises using a first transconductance amplifier to produce the error signal, the first transconductance amplifier having an input coupled to the error signal and an output of a second transconductance amplifier, sensing the current comprises using the second transconductance amplifier to produce the sensed current signal, the second transconductance amplifier having an output coupled to a current comparison output of the first transconductance amplifier, and comparing the first signal with the first threshold comprises using a current comparator comprising an input coupled to the current comparison output of the first transconductance amplifier; producing a first edge of a drive signal at a first edge of the clock signal; and producing a second edge of the drive signal when the first signal crosses the first threshold in a first direction based on the comparing, the second edge opposite the first edge.