Patent ID: 7019504

Claim:
A controller for generating an ON-time for a buck regulator receiving a regulator input voltage and generating a regulated output voltage, said controller comprising: circuitry for sensing said regulated output voltage and generating a sensed output voltage proportional to said regulated output voltage; circuitry for adding a first voltage ramp to said sensed output voltage to generate a modified sensed output voltage; circuitry for adding a second voltage ramp to a first reference voltage to generate a ripple reference voltage; circuitry for processing said ripple reference voltage to generate a modified reference voltage; circuitry for comparing said modified sensed output voltage to said modified reference voltage generating a comparator output having a first logic state when said modified sensed output voltage is greater than said modified reference voltage and a second logic state when said modified sensed output voltage is less than said modified reference voltage; and circuitry for generating a control signal having a first logic state during said ON-time in response to said comparator output, said regulator input voltage and a second reference voltage, wherein said regulated output voltage receives energy directly from said regulator input voltage during said ON-time and said regulated output voltages receives stored energy from said regulator input voltage after said ON-time terminates.