Patent ID: 8278903
Filing Date: 2012-10-02
Classification: H02M,Y02B

Abstract:
1. A method of setting a pulse width modulation (PWM) DC operating point of a voltage regulator that generates a regulated output voltage from an input voltage, the method comprising: generating a first current signal from the input voltage; generating a second current signal that is proportional to the output voltage; dividing the first current signal by the second current signal to generate a third current signal; charging a capacitor with the third current signal to generate a ramp signal; generating an error voltage indicative of a level of the output voltage; and comparing the ramp signal to the error voltage to determine when to switch OFF a drive transistor of the voltage regulator and control a duty cycle of the drive transistor by PWM to regulate the output voltage, the drive transistor being configured to couple the input voltage to a load when switched ON.