Patent ID: 6396252
Filing Date: 2002-05-28
Classification: H02M,Y02B

Abstract:
A switching DC-to-DC converter which generates an output potential Vout at an output node in response to an input potential, said converter comprising:a switching controller configured to generate at least one switch control signal including a first switch control signal in response to a first feedback signal indicative of the output potential Vout and a second feedback signal indicative of kVout, where k is a constant, the switching controller having a switching period; and external circuitry including a first power switch and an inductor, wherein the first power switch has an input coupled to receive the input potential and an output coupled to a first node and is coupled to receive the first switch control signal, the inductor is coupled between the first node and the output node, and an inductor current flows through the inductor during operation of the converter, wherein the switching controller is configured to operate in a continuous mode in which the inductor current remains above zero and the first switch control signal causes the first power switch to operate with a continuous mode duty cycle determined by the first feedback signal, and the switching controller is configured to enter a discontinuous pulse skipping mode in response to the inductor current falling to zero, wherein in the discontinuous pulse skipping mode, the first switch control signal causes the first power switch to operate with a duty cycle which is the longer of a minimum duty cycle and a discontinuous mode duty cycle, wherein the discontinuous mode duty cycle is a duty cycle at which the converter would operate in response to said first feedback signal when said converter generates the output potential in response to the input potential during a discontinuous mode without pulse skipping.