Patent ID: 11876456
Assignee: ALPHA AND OMEGA SEMICONDUCTOR INTERNATIONAL LP
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A controller for a switching regulator, the switching regulator configured to receive an input voltage and to generate a regulated output voltage on an output node for driving a load, the controller comprising:
a buck control circuit configured to receive a first error signal indicative of a difference between a feedback voltage indicative of the regulated output voltage and a reference voltage, the buck control circuit configured to generate a first pulse width modulation (PWM) signal for driving a power stage, the power stage receiving the input voltage on an input node and delivering a first phase current through an inductor to the output node to which an output capacitor and a load are connected, the buck control circuit generating the first PWM signal to drive the regulated output voltage to a first voltage value lower than the input voltage; and
a boost control circuit configured to receive a second error signal indicative of at least a current sense signal relating to the current flowing in the power stage, the boost control circuit configured to generate a second pulse width modulation (PWM) signal to drive the power stage to cause a second phase current to flow from the output node to the input node to return charges stored on the output capacitor to the input node, thereby decreasing the regulated output voltage to a second voltage value lower than the first voltage value,
wherein in response to a first command, the buck control circuit is activated to generate the first PWM signal to drive the power stage to generate the regulated output voltage having the first voltage value; and in response to a second command, the boost control circuit is activated to generate the second PWM signal to drive the power stage to return charges stored at the output node on the output capacitor to the input node and to decrease the regulated output voltage at the output node to the second voltage value; and
wherein the second command comprises a decay command to instruct the controller to ramp down the regulated output voltage to the second voltage value, and in response to the second command, the controller activates the boost control circuit to return the charges stored on the output capacitor to the input node while driving the regulated output voltage to the second voltage value; and during a charge recycle period when the boost control circuit is activated to return the stored charges from the output capacitor, the controller responds to incoming commands or requests by providing a status indicator that the switching regulator is in a decay state even though the switching regulator is performing charge recycling.