| 主权项 |
1. A DC to DC buck converting controller, packaged in a package and adapted to control a DC to DC buck converting circuit which converts an input voltage into an output voltage for driving a load, the DC to DC buck converting controller comprising:
a feedback circuit, receiving a reference signal through a pin of the package and generating a feedback control signal according to the reference signal representative of a reference voltage and a feedback signal representative of the output voltage; a driving circuit, generating at least one control signal to control the DC to DC buck converting circuit according to the feedback control signal, and the driving circuit comprising an on-time period circuit which sets an on-time period of the DC to DC buck converting circuit according to a level of the reference voltage; and an anti-noise circuit coupled between the feedback circuit and the on-time period circuit, and the anti-noise circuit receives the reference signal and generates a trigger signal to the on-time period circuit when the feedback control signal is generated for an anti-noise time, which is modulated in response to the reference voltage, wherein when the level of the reference voltage is varied, the anti-noise time is accordingly adjusted, wherein the level of reference voltage is synchronously adjusted by the DC to DC buck converting controller with a loading of the load, the level of the reference voltage is increased while the loading is increased, such that the on-time period is lengthened, and the level of the reference voltage is decreased while the loading is decreased, such that the on-time period is shortened. |
