Patent ID: 8866464

Claim:
A power supply system comprising: a switching converter that provides an output voltage by alternately turning on and off between opposing states a high-side transistor and a low-side transistor both coupled to an output inductor through a switching node, the switching converter including a drive circuit that regulates the output voltage based on a feedback signal; and a simulated output generator that generates and provides the drive circuit with a simulated inductor waveform as the feedback signal based on a low-side output waveform of the low-side transistor measured at the switching node during off-times of the switching converter, wherein a first control loop comprises a first transconductance amplifier with an output coupled to a first compensation network capacitor and with inputs that receive the simulated inductor waveform and the amplified, inverted version of the low-side output waveform, the first control loop regulates slopes of the simulated inductor waveform with the amplified, inverted version of the low-side output waveform and a second control loop comprises a second transconductance amplifier with an output coupled to a second compensation network capacitor and with inputs that receive sampled minimum values of the simulated inductor waveform and sampled minimum values of the amplified, inverted version of the low-side output waveform, the second control loop regulates minimum values of the simulated inductor waveform with the amplified, inverted version of the low-side output waveform; further comprising a charging capacitor that charges to produce on-times of the simulated inductor waveform and discharges to produce off-times of the simulated inductor waveform, wherein the first control loop controls the modulation of the charging of the charging capacitor and the second control loop controls the modulation of the discharging of the charging capacitor.