Abstract: A low dropout regulator (LDO) is disclosed. The LDO includes a transistor loop including a first transistor coupled to a second transistor. The first transistor and the second transistor coupled to a first resistor and a second resistor. The first resistor being coupled to ground and second resister coupled to the first resistor. The LDO further includes an output transistor coupled to the second transistor and a power supply line. The output transistor further coupled to a pair of input transistors coupled to the power supply line. One of the input transistors coupled to a third resistor, wherein the third resistor coupled to a fourth resistor and the fourth resistor coupled to ground. The LDO also includes a fifth resistor coupled to an output of the output transistor. The fifth resistor is coupled to the first transistor.

Abstract: A state machine for a multi-phase voltage converter controls cycle-by-cycle switching of the phases by: entering a first state in which a control signal for the high-side switch is activate and control signals for the low-side and SR (synchronous rectification) switches are deactivate; entering a second state in which the control signals for all switches are deactivate; entering a third state in which the control signal for the high-side switch is deactivate and the control signals for the low-side and SR switches are activate; entering a fourth state in which the control signals for the high-side and low-side switches are deactivate and the control signal for the SR switch is activate and then entering a fifth state in which the control signals for all switches are deactivate, or entering the fifth state without entering the fourth state; and entering the first state at the beginning of the next switching cycle.

Abstract: On embodiment pertains to a method including determining if an amplitude of an error signal has entered steady state. If the amplitude of the error signal has not entered steady state, then amplify with a high gain the amplitude of the AC component of the error signal. If the amplitude of the error signal has entered steady state, then initiate a timer. Determining if the amplitude of the error signal has remained in steady state while the timer runs. If the amplitude of the error signal has remained in steady state while the timer runs, then amplify with a low gain the amplitude of the AC component of the error signal.

Abstract: Systems and methods to generate drive current in a power supply, independent of the input voltage, are provided. The power supply includes front end circuitry, control circuitry, and drive circuitry. The front end circuitry includes protection circuitry to defend against damage from EMI, voltage spikes, and the like. The control circuitry includes startup circuitry, power factor correction (PFC) circuitry, and output power configuration circuitry. The startup circuitry provides operational voltage to the PFC circuitry, derived from an input voltage, until an internally generated operational voltage becomes available. The PFC circuitry uses the operational voltage to generate output power for the drive circuitry based on the output power configuration circuitry. The drive circuitry includes drive current configuration circuitry to generate a drive current to drive a load, coupled to the power supply, independent of the input voltage.

Abstract: Split phase power conversion apparatuses, methods and systems are disclosed. One exemplary embodiment includes a generator, an AC/DC converter coupled with the generator, a DC bus coupled with the AC/DC converter, and an inverter coupled with the DC bus. The inverter includes first, second, and third legs each including a plurality of switches. A first controller provides a control signal to the first leg based upon a voltage between a first system output and a second system output and a first current provided to the first system output. A second controller provides a second control signal to the second leg based upon a voltage between the second system output and a third system output and a second current provided to the third system output. A third controller controls the third leg to provide an output equal to one half of the DC bus voltage.

Abstract: A synchronous rectifier comprises at least one rectification switch (102, 103), and a control circuit (104) for controlling the at least one rectification switch to allow unidirectional current flow only. The control circuit comprises at least one current sensor (105, 106) for sensing an alternating component of current of the at least one rectification switch, and at least one driver circuit (107, 108) for controlling the at least one rectification switch at least partly on the basis of the direction of the sensed alternating component. Using the alternating component for controlling the rectification switch removes a need to compare the current to any non-zero constant or adjustable threshold value, and thus challenges related to defining the threshold value can be avoided. The synchronous rectifier can be for example a part of a resonant converter.

Abstract: The present invention discloses a current regulator circuit capable of reducing current ripple and a method of reducing current ripple. A power supply circuit generates a load current which originally has a current ripple. The load current is supplied to a load circuit. The current regulator circuit includes a regulator switch coupled to the load circuit, a current sense circuit for sensing the load current, and a control circuit. The control circuit controls the regulator switch to regulate a peak of a current sense signal minus an average of the current sense signal to a non-negative first predetermined value, or regulate the peak minus a valley of the current sense signal to a non-negative second predetermined value.

Abstract: A power conversion device includes a first detection circuit that acquires input information about an AC voltage and/or an alternating current which are inputted to the power conversion device from an AC power supply, a rectifier circuit, an inverter circuit including a switch, and a control circuit that generates a pulse signal for the switch while the control circuit (A) determines, based on the input information, whether the rectifier circuit is in a state in which the rectifier circuit allows switching noise to propagate from the switch to the AC power supply and (B) changes a frequency of the pulse signal with time at least in a period in which the rectifier circuit is in the state.

Abstract: A control circuit for a switch mode power supply (SMPS) includes a power switch for coupling to a primary winding of the power supply and a startup resistor coupled to an external input voltage and to a control terminal of the power switch. The control circuit also includes a controller. During startup, the controller is configured to cause the power switch to amplify a startup current from an external input voltage through the startup resistor and provide a startup power to the controller. During normal operation, the controller is configured to provide a power switch control signal to turn on and off the power switch for controlling a current flow in the primary winding and regulating an output of the power supply. The controller is configured to provide a current signal for driving an NPN power switch and to provide a voltage signal for driving an NMOS power switch.

Abstract: A power supply apparatus (10) includes a voltage input side (102), a power switch circuit (104), a voltage output side (106), a pulse width modulation signal generating circuit (108) and a burst frequency detection circuit (110). According to a pulse width modulation signal (114), the pulse width modulation signal generating circuit (108) controls the power switch circuit (104), so that the power supply apparatus (10) enters a burst mode. The burst frequency detection circuit (110) detects a burst frequency of the power switch circuit (104). The burst frequency detection circuit (110) informs the pulse width modulation signal generating circuit (108) that the burst frequency is in an audio frequency range if the burst frequency is in the audio frequency range. The power supply apparatus (10) leaves from the burst mode to avoid audio noise.

Abstract: A method of controlling a DC/AC converter (2) comprises the steps of (a) providing a desired AC side reference value (VAmp); (b) setting a reference correction value (VAmp,corr,1); (c) calculating an AC side reference signal (VAC,set,1) as a function of the desired AC side reference value (VAmp) and the reference correction value (VAmp,corr,1); (d) obtaining an actual AC side signal (VAC,Act,1); and (e) calculating a converter control signal (MAC,1) as a function of the AC side reference signal (VAC,Set,1) and the actual AC side signal (VAC,Act,1); wherein the setting of the reference correction value (VAmp,corr,1) is based on a relation of the desired AC side reference value (VAmp) and the actual AC side signal (VAC,Act,1).

Abstract: A converter performs full-wave rectification on a single-phase voltage, thus outputting a rectified voltage across DC power supply lines. An inverter receives the rectified voltage and then supplies a three-phase AC current to an inductive load. Between the DC power supply lines is connected a charge and discharge circuit. The charge and discharge circuit includes a buffer circuit and a boost circuit. The buffer circuit includes a series connection between a capacitor and a switch. The boost circuit, which may be configured by a boost chopper, includes a switch, a reactor and a diode. The charge and discharge circuit provides and receives part of pulsations of the power input to the converter between the DC power supply lines.

Abstract: A resonant power converter. An embodiment with a fullbridge converter is disclosed, controlled with feedback or feedforward technique. Switching schemes are either based on a sort of look up table or on measurement of current or voltage. Dead time may be adjusted. Timing may be such, that in the respective diagonal pairs of the converter, one switch is switched on for a different time (different pulse width) than the other. Use in a relative high power environment for about 20 KW in e.g. an X-Ray or Computer Tompgrapy System.

Abstract: A regulator circuit includes: a regulator part configured to generate a constant internal power supply voltage based on an external power supply voltage; a connection port configured to receive power from the regulator part and to be connected to a connection cable having a predetermined cable resistance, the connection cable is configured to electrically connect the connection port to an external device; a current detecting part configured to detect a power supply current when the connection cable is connected to the connection port; and a voltage compensation part configured to compensate a voltage corresponding to a voltage drop due to the cable resistance according to a current value detected by the current detecting part.

Abstract: A controller for a switched mode power converter includes limit-to-valley ratio circuitry, an on-time generator, and a drive circuit. The limit-to-valley ratio circuitry is coupled to generate a ratio signal in response to sensing a switch current of a switch that regulates an output of the switched mode power converter. The ratio signal is representative of a time ratio between a first length of time that the switch current is at or above a switch current limit and a second length of time that the switch current is at or below a switch current valley that is a portion of the switch current limit. The on-time generator is coupled to vary a switch on-time signal in response to receiving the ratio signal. The drive circuit is coupled to output a drive signal to a control terminal of the switch in response to receiving the switch on-time signal.

Abstract: A power control system includes a multi-phase power source, an ungrounded multi-phase load, a plurality of power switching circuits and a plurality of zero-crossing circuits. The multi-phase power source includes a plurality of phase power outputs. The plurality of power switching circuits are each connected to provide power from one of the plurality of phase power outputs to the ungrounded multiphase load. The plurality of zero-crossing circuits are connected to provide control signals to the plurality of power switching circuits. Each of the plurality of zero-crossing circuits are connected between one of the plurality of power phase outputs and an ungrounded reference.

Abstract: A method and device for switching an operation mode of a five-level inverter are provided. The method includes: determining a first three-level operation mode as a three-level operation mode to be switched to from a five-level operation mode in a case that a PV input voltage is higher than a bridge line-line voltage command value; switching, after the operation mode is switched to the first three-level operation mode, the operation mode from the first three-level operation mode to a second three-level operation mode, in a case that a junction temperature of a switching device operating in the first three-level operation mode exceeds a first preset value; and switching the operation mode from the second three-level operation mode to the first three-level operation mode in a case that the junction temperature of a switching device operating in the second three-level operation mode exceeds a second preset value.

Abstract: According to an embodiment, a circuit comprising includes a first switching circuit coupled to a power supply input, a second switching circuit coupled to an output of the first switching circuit, a supply capacitor coupled to the second switching circuit, and a startup cell coupled to the power supply input and the supply capacitor. The startup cell is configured to electrically couple the power supply input to the supply capacitor when the second switching circuit is not actively switching. The startup cell is also configured to electrically decouple the power supply input from the supply capacitor when the second switching circuit is actively switching.

Abstract: An electronic converter circuit system and a control method are disclosed. The electronic converter circuit system has a digital control platform, centered on a digital control chip, consisting of a hardware circuit and software, and built in with single-end, push-pull, half-bridge, full-bridge type control modes. By simple setting, the circuit system works in corresponding modes. The electronic converter circuit system mainly controls the field-effect tubes and IGBT. Control orders in the control process are output after comprehensive diagnosis of the modules by the software control platform. During conversion, the circuit works stably and has high conversion efficiency.

Abstract: A self-excited push-pull converter, where between the bases of the push-pull converter's transistors (TR1, TR2) and the effective power suppler there is provided a constant current source (II), which provides a constant current to the bases of the transistors. With the working voltage increases, the circuit enters into an operating mode not based on the core-saturation working mode, because the transistors' base current is limited by the constant current source and consequently the transistors' collector current cannot increase.