Abstract: Discharge systems for electric vehicles and electric vehicles having discharge systems. In one implementation, a discharge system for an electric vehicle includes a step-down power converter configured to step down an input voltage to an output voltage; discharge circuitry coupled to the output of the step-down power converter, wherein the discharge circuitry is reversibly driveable to load the step-down power converter; an input component configured to receive input that originated from a human user or a sensor of the electric vehicle, wherein the input indicates that the electric vehicle is to shutdown; and discharge drive circuitry configured to drive the discharge circuitry to load the step-down power converter in response to the indication that the electric vehicle is to shutdown.

Abstract: Silicon carbide (SiC) junction field effect transistors (JFETs) are presented herein. A deep implant (e.g., a deep p-type implant) forms a JFET gate (106). MET gate and MET source (108) may be implemented with heavily doped n-type (N+) and heavily doped p-type (P+) implants, respectively. Termination regions may be implemented by using equipotential rings formed by deep implants (e.g., deep p-type implants).

Abstract: Pulse sharing control to enhance performance in multiple output power converters is described herein. During a switching cycle, an energy pulse is provided to more than one port (i.e., output) using pulse sharing transfer. Pulse sharing transfer may enhance performance by reducing audible noise due to subharmonics and by reducing a root mean square current of one or more secondary currents. A primary switch is closed to energize an energy transfer element via a primary current. Energy may be shared among a first load port on a first circuit path via a first secondary current and among a second load port on a second circuit path via a second secondary current.

Abstract: Presented herein is a circuit path configuration for enhancing overvoltage protection in a switching power supply, the switching power supply comprising a bridge rectifier, a primary side switch, and a controller. The circuit path configuration implements input OVP by availing a clamping voltage indicative of a drain-to-source voltage of the primary side switch. The bridge rectifier provides a rectified voltage to a first node. The primary side switch comprises a drain; and the drain is electrically coupled to the first node via a first circuit path. The first circuit path comprises a first circuit path node between the first node and the drain. The controller comprises a voltage monitor input electrically coupled to the first circuit path node via a second circuit path; and the second circuit path provides a monitor voltage to the voltage monitor input.

Abstract: A primary controller configured for use in a power converter comprising a control circuit configured to determine a mode of operation of the power converter in response to a drive signal of a power switch. The control circuit further configured to generate a control signal in response to a signal representative of the mode of operation of the power converter, wherein the control signal represents a delay time to enable a turn on of the power switch after a turn off of a clamp switch. The control circuit further configured to generate a clamp drive signal to control the clamp switch. The primary controller further comprises a drive circuit configured to generate a drive signal to enable the power switch to transfer energy from an input of the power converter to an output of the power converter.

Abstract: A resonant power converter controller comprising a control circuit configured to turn on a synchronous rectifier (SR) in response to a count of a number of times a drain voltage of the SR crosses below a turn on threshold based on a stored count and turns off the SR when the drain voltage crosses above a turn off threshold. The control circuit comprises a first comparator configured to generate a first detection signal in response to the drain voltage being less than the turn on threshold. A first turn on detection circuit generates a first turn on signal when the count reaches the stored count. A first turn off signal is generated in response to the drain voltage being greater than the turn off threshold. A drive circuit turns on and off the SR in response to the first turn on signal and the first turn off signal.

Abstract: A magnet comprising a center disc having a center disposed as a center of the magnet, a face of the center disc is substantially perpendicular to a central axis of the magnet. The magnet further comprises a first plurality of outer discs disposed around the center disc in a bundled rod construction, a face of each of the first plurality of outer discs substantially perpendicular to the central axis of the magnet, wherein the center disc and each disc of the first plurality of outer discs is electrically insulated from every other disc.

Abstract: A controller configured for use in a power converter. The controller includes a control circuit coupled to receive an input line voltage sense signal representative of an input voltage of the power converter. The control circuit is configured to generate a control signal in response to a request signal representative of an output of the power converter. The control signal represents a delay time to turn on a power switch after a turn on of a clamp switch in response to the input line voltage sense signal. The control circuit can further generate a clamp drive signal to control a clamp driver and a drive circuit configured to generate a drive signal to control the power switch to transfer energy from an input of the power converter to the output of the power converter.

Abstract: A power converter includes a primary winding and multiple output windings to provide multiple independently controlled and regulated outputs with a common return line. The outputs are coupled to independently regulate constant current, constant voltage, or both constant current and constant voltage outputs. A secondary control block is coupled to control a synchronous rectifier switch coupled to the common return line to synchronize switching with a primary side power switch to provide complementary conduction of the primary winding and the multiple output windings. A plurality of controlled power pulse switches is coupled to the multiple output windings. A request of a power pulse from each of the outputs is transferred through the secondary control block to a primary switch control block to turn on the primary side power switch to transfer a power pulse to the multiple output windings and through controlled power pulse switches to the outputs.

Abstract: A power supply comprising a first-stage capacitor configured to provide energy to a second stage power converter. An energy transfer element coupled to the first-stage capacitor. A reservoir capacitor coupled to the energy transfer element. The reservoir capacitor is configured to receive charge from the energy transfer element. A power switch configured to control a transfer of energy from an input of the power supply to the first-stage capacitor. A controller coupled to the power switch, the controller configured to generate a hold-up signal in response to the input of the power supply falling below a threshold voltage. A charge circuit comprising a first switch and a second switch configured to be controlled by the hold-up signal. The first switch couples the reservoir capacitor to an input of the energy transfer element. The second switch is configured to uncouple the reservoir capacitor from receiving charge from the energy transfer element.

Abstract: Pulse sharing control to enhance performance in multiple output power converters is described herein. During a switching cycle, an energy pulse is provided to more than one port (i.e., output) using pulse sharing transfer. Pulse sharing transfer may enhance performance by reducing audible noise due to subharmonics and by reducing a root mean square current of one or more secondary currents. A primary switch is closed to energize an energy transfer element via a primary current. Energy may be shared among a first load port on a first circuit path via a first secondary current and among a second load port on a second circuit path via a second secondary current.

Abstract: A method for providing a jitter signal for modulating a switching frequency of a power switch for a power converter. The method comprising receiving a drive signal representative of the switching frequency of the power switch, detecting the switching frequency from the drive signal, determining if the switching frequency is less than a first threshold frequency, and modulating a frequency of the jitter signal in response to determining if the switching frequency is less than the first threshold frequency.

Abstract: A power converter controller includes a control loop clock generator to generate a switching frequency signal responsive to a burst load threshold, a power signal, and a load signal. A switching frequency of the switching frequency signal is above a resonance range of an energy transfer element. A burst control circuit generates a burst on signal and a burst off signal in response to a feedback signal and a burst enable signal to operate the controller in a plurality of burst modes. A burst frequency of the burst on signal or the burst off signal is less than the resonance range of the energy transfer element. A request transmitter circuit generates a request signal responsive to the switching frequency signal, the burst on signal, and the burst off signal to control switching of a switching circuit.

Abstract: A turn-off circuit for a semiconductor switch includes an element having a variable resistance coupled to a control input of the semiconductor switch, a circuit for generating a control-input reference signal, and a control circuit coupled to adjust a resistance of the element having a variable resistance in response to the control-input reference signal in a closed control loop in order to turn off the semiconductor switch.

Abstract: A power converter, comprising an energy transfer element, an output of the power converter, a power switch, an active clamp circuit, and a first controller. The active clamp circuit comprising a capacitance, a steering diode network coupled to the capacitance and configured to transfer a charge to the capacitance, a clamp switch coupled to the capacitance and configured to transfer the charge stored in the capacitance to the energy transfer element, and an offset element coupled to the clamp switch and configured to provide a path to discharge a capacitance associated with the clamp switch. The first controller configured to output a clamp drive signal to control the turn on and turn off of the clamp switch and a primary drive signal to control the turn on and turn off of the power switch.

Abstract: A power converter comprising an energy transfer element is coupled between an input of the power converter and an output of the power converter. A cascode circuit generates a first sense signal and a second sense signal. A controller controls the switching of the cascode circuit to transfer energy from the input of the power converter to the output of the power converter. The controller comprising a current sense circuit generates a current limit signal and an overcurrent signal in response to the first sense signal and the second sense signal. A control circuit generates a control signal in response to the current limit signal and the overcurrent signal. A drive circuit comprising a first stage gate drive circuit generates a drive signal in response to the control signal to reduce EMI, and a second stage of gate drive circuit to enable accurate current sensing of the cascode circuit.

Abstract: A current matching circuit includes a plurality of LED driver circuits. A current to voltage converter circuit is coupled to the plurality of LED driver circuits to generate a plurality of voltage signals. Each one of the plurality of voltage signals is representative of a respective output current through a corresponding one of the plurality of LED driver circuits. A comparison circuit is coupled to the current to voltage converter circuit to compare the plurality of voltage signals. An adjustment circuit is coupled to the comparison circuit and the plurality of LED driver circuits. The adjustment circuit is configured to trim the plurality of LED driver circuits in response to the comparison circuit such that each respective output current through the plurality of LED driver circuits is substantially equal.

Abstract: A controller for a power converter comprising a drive signal generator and drive strength control and a variable strength multi-stage gate driver. The drive signal generator and drive strength control outputs a drive signal to control switching of a power switch and a strength signal to control drive strength of the power switch. The variable strength multi-stage gate driver is configured to turn ON the power switch in response to the drive signal with a first drive strength then a second drive strength when the strength signal is not asserted. The variable strength multi-stage gate driver is configured to turn ON the power switch in response to the drive signal with a third drive strength then the second drive strength when the strength signal is asserted. The second drive strength is stronger than the first drive strength and the first drive strength is stronger than the third drive strength.

Abstract: An auxiliary converter coupled to an output of a main power converter comprising an auxiliary switch, a timing circuit, and an energy transfer element. The auxiliary switch coupled to the output of the main power converter. A timing circuit coupled to receive a control signal from a controller of the main power converter, wherein the controller regulates the output of the main power converter, the timing circuit configured to output an auxiliary drive signal to control switching of the auxiliary switch in response to the control signal. The energy transfer element coupled to the auxiliary switch, wherein the energy transfer element is configured to transfer energy from the output of the main power converter to a supply of the controller, the supply provides operational power for the controller of the main power converter.

Abstract: An energy transfer element comprises a U-shaped core of powder core, the U-shaped core having two legs and a gap in a magnetic path, a bar comprising magnetizable material positioned in the gap such that the magnetic core and magnetizable material form a rectangular toroid, and one or more power windings wrapped around the magnetic path. The magnetizable material is capable of being magnetized. When the magnetizable material is unmagnetized, the magnetizable material has an initial flux density. When the magnetizable material is magnetized, the flux density produced by the magnetized material is offset from the initial flux density. The magnetizable material is an unmagnetized magnet or a suspension medium such as epoxy with magnetized magnetizable particles and powder core. The magnetizable particles are selected from a group comprising Neodymium Iron Boron (NdFeB) based materials or Samarium Cobalt (SmCo) based material.