Abstract: In one embodiment, a method of forming a semiconductor device may include forming a sense resistor to receive a high voltage signal and form a sense signal that is representative of the high voltage signal. An embodiment of the sense resistor may optionally be formed overlying a polysilicon resistor. The method may also have an embodiment that may include forming a plurality of capacitors in parallel to portions of the sense resistor wherein the plurality of capacitors are connected together in series.

Abstract: In one embodiment, a method of forming a semiconductor device may include forming a sense resistor to receive a high voltage signal and form a sense signal that is representative of the high voltage signal. An embodiment of the sense resistor may optionally be formed overlying a polysilicon resistor. The method may also have an embodiment that may include forming a plurality of capacitors in parallel to portions of the sense resistor wherein the plurality of capacitors are connected together in series.

Abstract: In one form, a power factor correction (PFC) controller, comprising includes a regulation circuit, a dead-time detection circuit, and a pulse width modulator. The regulation circuit provides a control voltage in response to a feedback voltage received at a feedback input terminal, wherein the feedback voltage is proportional to an output voltage. The dead-time detection circuit has an input coupled to a zero current detection input terminal, and an output for providing a dead-time signal. The pulse width modulator is responsive to the control voltage and the dead-time signal to provide a drive signal that controls conduction of a switch to improve a power factor of an offline converter, wherein the pulse width modulator modulates both an on-time and a switching period of the drive signal using the dead-time signal in a discontinuous conduction mode.

Abstract: A circuit and method for detecting a brown-out condition and providing a feed-forward transfer function in a power supply circuit. A comparison circuit is coupled to a delay element through a latch. A second delay element is connected between the first delay element and an input of the latch. The output of the first delay element is connected to a clamping circuit via a logic circuit. A first voltage is compared with a reference voltage to generate a comparison voltage, which is transmitted through the latch and the first delay element. The comparison voltage is monitored at an output of the first delay element. A brown-out condition occurs if the comparison voltage being monitored at the output of the first delay element results from the first voltage being less than the reference voltage.

Abstract: A circuit and method for detecting a brown-out condition and providing a feed-forward transfer function in a power supply circuit. A comparison circuit is coupled to a delay element through a latch. A second delay element is connected between the first delay element and an input of the latch. The output of the first delay element is connected to a clamping circuit via a logic circuit. A first voltage is compared with a reference voltage to generate a comparison voltage, which is transmitted through the latch and the first delay element. The comparison voltage is monitored at an output of the first delay element. A brown-out condition occurs if the comparison voltage being monitored at the output of the first delay element results from the first voltage being less than the reference voltage.

Abstract: A method and circuit for protecting against an over current condition. A conduction time of one or more transistors is reduced during the over current condition. The conduction time is reduced in an amount that is an increasing function of the amount of the over current. The conduction time may be reduced proportionally to the excess current.

Abstract: A circuit and method for detecting a brown-out condition and providing a feed-forward transfer function in a power supply circuit. A comparison circuit is coupled to a delay element through a latch. A second delay element is connected between the first delay element and an input of the latch. The output of the first delay element is connected to a clamping circuit via a logic circuit. A first voltage is compared with a reference voltage to generate a comparison voltage, which is transmitted through the latch and the first delay element. The comparison voltage is monitored at an output of the first delay element. A brown-out condition occurs if the comparison voltage being monitored at the output of the first delay element results from the first voltage being less than the reference voltage.

Abstract: In accordance with an embodiment, a controller includes a comparator, a delay element, and a timer. The delay element is connected to an input terminal of the comparator and the timer is connected to an output terminal of the comparator. The delay element may include a switch having a control electrode coupled for receiving a control signal. In accordance with another embodiment, a detection signal is generated in response to a comparison signal transitioning to a first level.

Abstract: A method and circuit for protecting against an over current condition. A conduction time of one or more transistors is reduced during the over current condition. The conduction time is reduced in an amount that is an increasing function of the amount of the over current. The conduction time may be reduced proportionally to the excess current.

Abstract: In one embodiment, a PWM controller is configured to form a drive signal that has an operating frequency that varies around a center by a percentage of the center frequency.

Abstract: In one embodiment, a PWM controller is configured to form a drive signal that has an operating frequency that varies around a center by a percentage of the center frequency.

Abstract: In one embodiment, a PWM controller is configured to form a control signal that has reduced noise. The control signal is used to adjust a frequency of a clock signal of the PWM controller.

Abstract: In one embodiment, a power supply controller uses a ramp signal to form current sense ramp compensation.

Abstract: In one embodiment, a power supply controller uses a ramp signal to form current sense ramp compensation.