Patent ID: 9712061
Date: 2017-07-18
CPC Classifications: H02M,Y02B

Claim:
1. A method to control a power converter comprising: regulating an output using a switching circuit that responds to a control signal; comparing a feedback voltage from the output to a reference voltage using an error amplifier to create an error voltage; comparing the error voltage to a ramp voltage from a periodic ramp signal using a comparator to create a pulse width modulated signal, wherein the pulse width modulated signal is used in combination with the switching circuit to regulate the output; clamping the error voltage, using a clamping circuit, if the error voltage drops below a lowest value for the periodic ramp signal while the power converter is regulating a load; unclamping the error voltage, using the clamping circuit, if the error voltage rises above the lowest value for the periodic ramp signal while the power converter is regulating the load; comparing the error voltage to a second reference voltage using a second comparator, wherein the second comparator: (i) sets a state of the clamping circuit to unclamped or clamped; and (ii) controls a current through a sense resistor; transitioning the switching circuit into a tristate wherein the output floats; and generating a second control signal, using the sense resistor, to pull the switching circuit out of the tristate.