Abstract: A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R1 and R2, and third and second temperature coefficients, TC3 and TC2, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC1, is substantially equal to TC2×(R2/(R1+R2))+TC3×(R1/(R1+R2)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

Abstract: A control circuit for use in a power converter with an unregulated dormant mode of operation includes a drive signal generator coupled to generate a drive signal to control switching of a power switch in response to an energy requirement of one or more loads to be coupled to the power converter output. An unregulated dormant mode control circuit is included and is coupled to render dormant the drive signal generator when the energy requirement of the one or more loads falls below a threshold for more than a first period of time. The unregulated dormant mode control circuit is coupled to power up the drive signal generator after a second period of time has elapsed. The drive signal generator is coupled to again be responsive to changes in the energy requirement of the one or more loads after the second period of time has elapsed.

Abstract: A regulator for a switched mode power supply includes switching regulator logic, a counter and a switching transistor. The switching regulator logic is coupled to receive a feedback signal and to generate a switching signal in response. The feedback signal periodically cycles between a first state and a second state when the power supply operates normally. The counter is coupled to receive the feedback signal and an output of the counter indicates an auto-restart mode of the regulator in response to the feedback signal remaining in the first state for a predetermined count. The switching transistor is turned on and off in response to the switching signal when the output of the counter does not indicate the auto-restart mode and is disabled when the output of the counter indicates the auto-restart mode.

Abstract: A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R1 and R2, and third and second temperature coefficients, TC3 and TC2, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC1, is substantially equal to TC2×(R2/(R1+R2))+TC3×(R1/(R1+R2)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

Abstract: A circuit to control the slew rate of charging a capacitance using the capacitance is disclosed. An example circuit includes a regulator circuit to regulate a supply voltage during a normal operation mode of the circuit. A capacitance circuit is coupled to the regulator circuit. The regulator circuit is coupled to charge a capacitance between a first node and a second node of the capacitance circuit with a charge current. A slew rate control circuit is coupled to the regulator circuit and the capacitance circuit. The slew rate control circuit sets a slew rate of a voltage between the first and second nodes during a power up mode of the circuit.

Abstract: A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R1 and R2, and third and second temperature coefficients, TC3 and TC2, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC1, is substantially equal to TC2×(R2/(R1+R2))+TC3×(R1/(R1+R2)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

Abstract: A regulator for a switched mode power supply includes switching regulator logic, a counter and a logic gate. The switching regulator logic is coupled to receive a feedback signal and to generate a switching signal in response. The feedback signal periodically cycles between a first state and a second state when the power supply operates normally. The counter is coupled to receive the feedback signal and an output of the counter indicates an auto-restart mode of the regulator in response to the feedback signal remaining in the first state for a predetermined count. An output of the logic gate enables the power switch to turn on and off in response to the switching signal when the output of the counter does not indicate the auto-restart mode and the output of the logic gate disables the power switch in response to the output of the counter indicating the auto-restart mode.

Abstract: A control circuit for use in a power converter with an unregulated dormant mode of operation includes a drive signal generator coupled to generate a drive signal to control switching of a power switch to be coupled to the control circuit to regulate a flow of energy to a power converter output in response to an energy requirement of one or more loads to be coupled to the power converter output. An unregulated dormant mode control circuit is included and is coupled to render dormant the drive signal generator thereby ceasing the regulation of the flow of energy to the power converter output by the drive signal generator when the energy requirement of the one or more loads falls below a threshold for more than a first period of time. The drive signal generator is coupled to be unresponsive to changes in the energy requirements of the one or more loads when dormant. The unregulated dormant mode control circuit is coupled to power up the drive signal generator after a second period of time has elapsed.

Abstract: A controller for a power supply includes a logic block and a time-to-frequency converter. The logic block is to generate a drive signal in response to a clock signal. The drive signal is to be coupled to control switching of a power switch of the power supply to regulate an output of the power supply. The time-to-frequency converter is coupled to the logic block and generates the clock signal having a frequency responsive to a time period of the drive signal.

Abstract: An example apparatus to regulate an output voltage of a power converter at light/no load conditions includes a driver circuit, a feedback circuit, and an adjustable voltage reference circuit. The driver circuit is coupled to output a drive signal to switch a power switch between an ON state and an OFF state to regulate an output of the power converter. The feedback circuit is coupled to the driver circuit and is further coupled to output an enable signal to switch the power switch to an ON state in response to an output voltage signal. The adjustable voltage reference circuit is coupled to adjust a voltage reference such that a bias winding voltage of the power converter is adjusted nonlinearly in response to a load that is to be coupled to the output of the power converter.

Abstract: A switched mode controller for properly handling an under-voltage condition in a power line which includes a current mirror for receiving current from the power line; a reference current source coupled to the current mirror for supplying a reference current; and a power transistor coupled to the reference current source, the power transistor generating a pulse width modulated signal when current from the power line exceeds the reference current, the power transistor being disabled when current from the power line is less than the reference current.

Abstract: A power converter controller circuit is disclosed. In one aspect, a power converter controller circuit includes a control circuit to generate a switching signal to be coupled to a power switch to control power delivered to an output of a power converter. A timing circuit is to be coupled to the power switch and coupled to receive a feedback signal and the switching signal. The timing circuit is to disable the power switch from receiving the switching signal in response to the feedback signal after detection of a fault condition. The feedback signal repeatedly transitions between first and second states in response to the output when the power supply operates normally. The feedback signal maintains its state when the power supply is in the fault condition. The feedback signal transitions between the first and second states independently from the switching signal.

Abstract: A circuit protects a power conversion system with a feedback control loop from a fault condition. The circuit has an oscillator having an input for generating a signal with a frequency and a timer connected to the oscillator input and to the feedback control loop. The timer disables the oscillator after a period following the opening of the feedback control loop to protect the power conversion system.

Abstract: A DC to DC converter comprising an energy storage element comprising an energy storage element input and an energy storage element output, the energy storage element input coupled to receive a first power level and the energy storage element output providing a second power level. The converter also comprises a feedback circuit comprising a feedback input and a feedback output, the feedback input coupled to the energy storage element output. The converter further comprises a regulator circuit comprising a regulator circuit feedback input and a regulator circuit output, the regulator circuit feedback input coupled to the feedback output and the regulator circuit output coupled to the energy storage element input, the regulator circuit regulating the input of the first power level to the energy storage element input.

Abstract: A circuit protects a power conversion system with a feedback control loop from a fault condition. The circuit has an oscillator having an input for generating a signal with a frequency and a timer connected to the oscillator input and to the feedback control loop. The timer disables the oscillator after a period following the opening of the feedback control loop to protect the power conversion system.

Abstract: A DC to DC converter comprising an energy storage element comprising an energy storage element input and an energy storage element output, the energy storage element input coupled to receive a first power level and the energy storage element output providing a second power level. The converter also comprises a feedback circuit comprising a feedback input and a feedback output, the feedback input coupled to the energy storage element output. The converter further comprises a regulator circuit comprising a regulator circuit feedback input and a regulator circuit output, the regulator circuit feedback input coupled to the feedback output and the regulator circuit output coupled to the energy storage element input, the regulator circuit regulating the input of the first power level to the energy storage element input.

Abstract: A circuit protects a power conversion system with a feedback control loop from a fault condition. The circuit has an oscillator having an input for generating a signal with a frequency and a timer connected to the oscillator input and to the feedback control loop. The timer disables the oscillator after a period following the opening of the feedback control loop to protect the power conversion system.

Abstract: A power supply controller having a multi-function terminal. In one embodiment, a power supply controller for switched mode power supply includes a drain terminal, a source terminal, a control terminal and a multi-function terminal. The multi-function terminal may be configured in a plurality of ways providing any one or some of a plurality of functions including on/off control, external current limit adjustments, under-voltage detection, over-voltage detection and maximum duty cycle adjustment. The operation of the multi-function terminal varies depending on whether a positive or negative current flows through the multi-function terminal. A short-circuit to ground from the multi-function terminal enables the power supply controller. A short-circuit to a supply voltage from the multi-function terminal disables the power supply controller. The current limit of an internal power switch of the power supply controller may be adjusted by externally setting a negative current from the multi-function terminal.

Abstract: A DC to DC converter comprising an energy storage element comprising an energy storage element input and an energy storage element output the energy storage element input coupled to receive a first power level and the energy storage element output providing a second power level. The converter also comprises a feedback circuit comprising a feedback input and a feedback output, the feedback input coupled to the energy storage element output. The converter further comprises a regulator circuit comprising a regulator circuit feedback input and a regulator circuit output, the regulator circuit feedback input coupled to the feedback output and the regulator circuit output coupled to the energy storage element input, the regulator circuit regulating the input of the first power level to the energy storage element input.

Abstract: Invasive remodelling in a mammal may be inhibited by (1) inhibiting or abolishing the protein cleaving action of plasmin and (2) inhibiting or abolishing the protein cleaving action of at least one additional proteolytic enzyme active in invasive remodelling, such as a metalloprotease.