Control circuit and method for programming an output voltage of a power converter
AssigneeRichtek Technology Corporation
InventorIsaac Y. Chen
Life of this patent
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Abstract
A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
Claims16
A control circuit for programming an output voltage of a power converter including a feedback loop configured to operably provide a feedback signal related to the output voltage so as to regulate the output voltage, the control circuit comprising:
- a voltage divider configured to operably divide the output voltage to generate a first voltage signal;
- an offset resistor having a first terminal and a second terminal;
- wherein, the first terminal of the offset resistor is coupled to the voltage divider for receiving the first voltage signal and the second terminal of the offset resistor is configured to operably output a second voltage signal for controlling the feedback signal;
- and
- an offset current generator coupled to the second terminal of the offset resistor and configured to operably inject a first current to the offset resistor or sink a second current from the offset resistor so as to offset the first voltage signal to generate the second voltage signal;
- wherein, the offset current generator adjusts the first current or the second current so as to adjust the second voltage signal, thereby changing the feedback signal and adjusting the output voltage.
A control method for programming an output voltage of a power converter including a feedback loop configured to operably provide a feedback signal related to the output voltage so as to regulate the output voltage, the control method comprising the steps of:
- dividing the output voltage to generate a first voltage signal to a first terminal of an offset resistor;
- injecting a first current to a second terminal of the offset resistor or sinking a second current from the second terminal of the offset resistor, thereby offsetting the first voltage signal to generate a second voltage signal to control the feedback signal;
- and
- adjusting the first current or the second current so as to adjust the second voltage signal, thereby changing the feedback signal and adjusting the output voltage.
Dependencies are inferred from the claim text.