Patent ID: 8350548
Filing Date: 2013-01-08
Classification: H02M

Abstract:
1. A frequency control circuit for a non-constant frequency voltage regulator including a first constant-time trigger to generate a pulse width modulation signal, a current generator to provide a first current to determine a constant on-time or a constant off-time for the pulse width modulation signal, and a power output stage operated by the pulse width modulation signal to generate a load current and having a power switch connected to a phase node to be switched by the pulse width modulation signal, the frequency control circuit comprising: a compensator connected to the phase node, for converting a difference between a pulse width of a phase node voltage detected from the phase node and the constant on-time or the constant off-time set by the first current into a second current; and an adder connected to the current generator, the first constant-time trigger, and the compensator, for adding the second current to the first current to supply to the first constant-time trigger to determine the on-time or the off-time of the pulse width modulation signal to control a frequency of the pulse width modulation signal.