Abstract: An emitter switched bipolar transistor circuit includes a bipolar junction transistor (BJT) having a collector coupled to an output terminal, a metal oxide semiconductor field effect transistor (MOSFET) coupled to an emitter of the BJT, a bias voltage supply coupled to the base of the BJT, a buffer coupled to the base of the BJT, and a comparator. The comparator includes a first input coupled to the collector of the BJT, a second input coupled to a voltage reference, and an output coupled to an input of the buffer. The comparator is configured to receive a collector voltage of the BJT at the first input of the comparator, compare the received collector voltage with the voltage reference, and cause the buffer to inject a current pulse to the base of the BJT until the collector voltage is less than the voltage reference, indicating the BJT is substantially saturated.

Abstract: A system includes first and second pluralities of single phase AC/DC power supplies each having an input for coupling to first and second phase voltages, respectively, in a polyphase power distribution system. The outputs of the power supplies are electrically connected in parallel for supplying DC current to a load at a substantially constant voltage. The system further includes a controller coupled to at least the first plurality of power supplies and configured to increase the DC current supplied to the load by at least one of the first plurality of power supplies in response to another one of the first plurality of power supplies shutting down. Various other systems, power supplies, controllers and methods are also disclosed.

Abstract: Example switching power converters and methods for reducing voltage changes at an output of a power converter are generally disclosed. According to one aspect, a switching power converter includes an input, an output for providing an output voltage, at least one switch capable of causing a voltage overshoot of the output voltage when the switch is turned on, and a controller. The controller is configured to sense the output voltage, compare the sensed output voltage to a voltage reference, and adjust operation of the power converter based on the comparison of the sensed output voltage and the voltage reference to maintain the output voltage. The controller is further configured to decrease the voltage reference from a normal operation value to an overshoot reduction value before turning on the switch to decrease the output voltage and reduce an overshoot of the output voltage in response to turning on the switch.

Abstract: An integrated circuit assembly includes a first electrically conductive sheet, a second electrically conductive sheet electrically isolated from the first electrically conductive sheet, a non-conductive material disposed between the first and second electrically conductive sheets, an electrical trace disposed on the non-conductive material and electrically isolated from the first and second electrically conductive sheets, and an integrated circuit having at least one lead directly connected to the first electrically conductive sheet, at least one lead directly connected to the second electrically conductive sheet, and at least one lead electrically connected to the electrical trace. Other integrated circuit assemblies and method for making integrated circuit assemblies are also disclosed.

Abstract: Control circuits are provided for regulating an output voltage of a switched mode power supply having a variable input voltage and at least one power switch. The control circuits are operable to generate a comparison voltage based on the output voltage of the switched mode power supply and a duty cycle of a control signal provided to the at least one power switch, determine a reference voltage based on whether the generated comparison voltage falls within one of a plurality of voltage ranges, and adjust the duty cycle of the control signal provided to the at least one power switch of the switched mode power supply as a function of the determined reference voltage and the output voltage. Each voltage range is associated with a different reference voltage. Switched mode power supplies including the control circuits and methods implemented by the control circuits are also disclosed.

Abstract: An input redundant circuit according to the present disclosure may include: a core power supply unit; a first input port connected to a first input voltage; a second input port connected to a second input voltage; a relay unit connected to the first input port and the second input port to supply one of the first input voltage and the second input voltage to the core power supply unit; and a surge current limiting unit coupled to the relay unit, configured to limit a surge current generated when the relay unit is switched between the first input voltage and the second input voltage.

Abstract: A control circuit for controlling a switching device having a first terminal, a second terminal, and a control terminal is disclosed. The control circuit includes a first diode for coupling to the first terminal of the switching device, a second diode for coupling to the second terminal of the switching device, a first transistor for coupling to the control terminal of the switching device, and a second transistor coupled to the second diode. The first transistor is coupled to the first diode. The control circuit is configured to allow current flow in only one direction between the first and second terminals of the switching device.

Abstract: An emitter switched bipolar transistor circuit includes a bipolar junction transistor (BJT) having a collector coupled to an output terminal, a metal oxide semiconductor field effect transistor (MOSFET) coupled to an emitter of the BJT, a bias voltage supply coupled to the base of the BJT, a buffer coupled to the base of the BJT, and a comparator. The comparator includes a first input coupled to the collector of the BJT, a second input coupled to a voltage reference, and an output coupled to an input of the buffer. The comparator is configured to receive a collector voltage of the BJT at the first input of the comparator, compare the received collector voltage with the voltage reference, and cause the buffer to inject a current pulse to the base of the BJT until the collector voltage is less than the voltage reference, indicating the BJT is substantially saturated.

Abstract: A power system includes a DC power source having a maximum output voltage, a DC/AC inverter having an input coupled via a connection to the DC power source and an output for supplying AC power to a load, and a control circuit for controlling the DC/AC inverter. The control circuit is configured to maintain a DC voltage at the input of the DC/AC inverter above a threshold voltage to inhibit arcing as a result of a break in the connection between the DC power source and the DC/AC inverter. The threshold voltage is substantially equal to the maximum output voltage of the DC power source less a minimum arcing voltage for the connection between the DC power source and the DC/AC inverter.

Abstract: A multi-stage power converter includes a pre-regulator circuit configured to provide a regulated output voltage, at least one DC/DC converter, and a control circuit coupled to the pre-regulator circuit and the DC/DC converter. The DC/DC converter is configured to provide an output voltage and an output current to a load. The DC/DC converter includes an input, an output, and at least one power switch. The input of the DC/DC converter is coupled to the pre-regulator circuit. The control circuit is configured to regulate the output voltage of the DC/DC converter and vary the regulated output voltage of the pre-regulator circuit as a function of the output current of the DC/DC converter.

Abstract: A switch controller for a variable output voltage power converter includes a pulse width modulator (PWM) output producing a pulsed signal for driving a power converter switch. A mode selector output is connected to a multiplier. A period selector output is connected to the multiplier and to a PWM input. The multiplier output is connected to another PWM input. A comparator output is connected to a period selector input. The period selector outputs a nominal cycle time to the PWM when an operating on-time state is greater than a minimum operating on-time. The period selector outputs an updated cycle time greater than the nominal cycle time when the operating on-time state is less than the minimum operating on-time causing the PWM to output a pulsed signal with the updated cycle time and a duty cycle equal to a duty cycle of an immediately preceding pulsed signal.

Abstract: A multiphase DC/DC power converter includes an input, an output, at least a first converter and a second converter coupled in parallel between the input and the output, an inductor coupled to the first and second converters, an output capacitor coupled between the first and second converters and the output, and a control circuit coupled to the first converter and the second converter. The first and second converters each include a power switch. The control circuit is configured to switch the power switches at a frequency with a phase shift therebetween, and to vary the frequency to regulate a voltage at the output. Additionally, the control circuit may be configured to switch power switches at a fixed frequency with substantially no phase shift therebetween during startup of a multiphase DC/DC power converter, and at a variable frequency with a defined phase shift therebetween after startup.

Abstract: A power supply includes a power circuit for converting an input voltage or current to an output voltage or current, at least one interface port for receiving signals from one or more external devices, and a control circuit coupled to the power circuit and the at least one interface port. The control circuit is adapted to operate the power circuit in response to control signals having a plurality of different control signal formats that are received by the at least one interface port.

Abstract: A filter for a power supply includes at least two inputs, at least two outputs, and a common mode choke coupled between the at least two inputs and the at least two outputs. Each input includes a pair of input terminals and each output includes a pair of output terminals. The common mode choke includes a magnetic core and at least four windings extending about the magnetic core. Each winding is coupled between one of the input terminals and one of the output terminals. The filter may further include X-capacitors coupled between the at least two inputs and the at least two outputs. Also disclosed are power supply systems including one or more power supplies and a filter coupled to the power supplies.

Abstract: A single phase redundant power supply system may include a first power supply having an input coupled to a first phase voltage in a polyphase power distribution system and an output coupled to a load for supplying an amount of DC power to the load, and a second power supply having an input for coupling to a second phase voltage in the polyphase power distribution system and an output coupled to the load for supplying an amount of DC power to the load. At least the first power supply is configured to reduce phase current imbalances in the polyphase power distribution system by adjusting the amount of DC power supplied to the load by the first power supply and the amount of DC power supplied to the load by the second power supply.

Abstract: A multiphase power converter includes a plurality of subconverters and a control circuit. Each subconverter has an input circuit, an output circuit, and a magnetic core coupling the input circuit to the output circuit. The magnetic core of at least one of the plurality of subconverters has a core section that is shared by the magnetic core of another one of the plurality of subconverters. The control circuit is configured to operate the input circuits of the plurality of subconverters with different phases. The magnetic cores may be cores of a transformer, a coupled inductor, etc.

Abstract: Various methods related to air moving devices in electronic systems are disclosed. Various electronic systems including controlled air moving devices are also disclosed. Thus, one example electronic system includes an air moving device and a controller for controlling the air moving device. The controller is configured to selectively control a rotational speed of the air moving device. The controller is configured to vary the rotational speed within a range bounded by and including a first rotational speed and a second rotational speed during a time that a target rotational speed is within the range.

Abstract: A resonant converter apparatus includes a plurality of resonant converters connected in parallel, and a control module outputting a pulse width modulation (PWM) control signal to the resonant converters. The control module includes a voltage control loop and a circuit control loop. The voltage control loop compares the sensed output voltage with a predetermined reference voltage, and outputs a PWM control signal to one of the resonant converters so the output voltage of the one converter is equal to the predetermined reference voltage. The current control loop uses the sensed output current of the one converter as a reference current, compares the reference current with the sensed output current from each of the other resonant converters, generates a frequency adjusting variable, and calculates the individual PWM control signal for each of the other converters so the output currents of the plurality of converters are the same.

Abstract: Methods of regulating an output voltage of a switched mode power supply having a variable input voltage and a power switch include adjusting a reference voltage to adjust a duty cycle of a control signal for the power switch. The reference voltage may be adjusted as a function of the duty cycle, in response to the duty cycle of the control signal being outside a defined range and/or in the response to a temperature within the switched mode power supply being above a threshold temperature. Other methods include selecting a reference voltage from a plurality of reference voltages based on a determined input voltage and generating a control signal for the power switch as a function of the selected reference voltage to adjust the duty cycle of the control signal. Switched mode power supplies and control circuits for implementing the methods are also disclosed.

Abstract: Methods of regulating an output voltage of a switched mode power supply having a variable input voltage and a power switch include adjusting a reference voltage to adjust a duty cycle of a control signal for the power switch. The reference voltage may be adjusted as a function of the duty cycle, in response to the duty cycle of the control signal being outside a defined range and/or in the response to a temperature within the switched mode power supply being above a threshold temperature. Other methods include selecting a reference voltage from a plurality of reference voltages based on a determined input voltage and generating a control signal for the power switch as a function of the selected reference voltage to adjust the duty cycle of the control signal. Switched mode power supplies and control circuits for implementing the methods are also disclosed.