A circuit is disclosed. The circuit includes a current detecting FET, configured to generate a current signal indicative of the value of the current flowing therethrough, an operational transconductance amplifier (OTA) configured to output a current in response to the voltage of the current signal, and a resistor configured to receive the current and to generate a voltage in response to the received current, where the generated voltage is indicative of the value of the current flowing through the current detecting FET. The current detecting FET is configured to become nonconductive in response to the generated voltage indicating that the current flowing through the current detecting FET is greater than a threshold.

Disclosed herein is a power control apparatus for sub-modules in an MMC, which controls stable supply of power to sub-modules in MMC connected to an HVDC system and a STATCOM. The power control apparatus includes at least one first resistor connected between P and N buses of MMC; a second resistor connected in series with the first resistor; a switch connected in series with the second resistor; a third resistor connected in parallel with the second resistor and the switch which are connected in series; a Zener diode connected in parallel with the third resistor; and a DC/DC converter connected between both ends of the Zener diode and configured to convert voltage across both ends of the Zener diode into low voltage, and supply the low voltage to the sub-modules, wherein a magnitude of current flowing through the Zener diode is controlled depending on ON/OFF switching of the switch.

According to one embodiment, a voltage converting device includes a DC power source; an inverter generating AC power; an AC component detector configured to detect an AC component of current flowing through a first terminal or a second terminal of the inverter in the DC power source side; and a phase estimator configured to estimate a phase relation between a phase of voltage of the AC power and a phase of current of the AC power based on an amplitude of a specific frequency component contained in a first absolute value signal of the AC component. The AC power generated by the inverter is supplied to a loading device, and an impedance of the loading device at a fundamental of a driving frequency of the inverter is smaller than an impedance of the loading device at an odd-order harmonic of the driving frequency.

A primary-side controlled high power factor, low total harmonic distortion, quasi resonant converter converts an AC mains power line input to a DC output for powering a load, such as a string of LEDs. The AC mains power line input is supplied to a transformer that is controlled by a power switch. A device for controlling a power transistor of a power stage includes a shaper circuit including a first current generator configured to output a first current responsive to a bias voltage signal and to generate a reference voltage signal based on the first current. A bias circuit includes a second current generator configured to output a second current responsive to a compensation voltage signal and to generate the bias voltage based on the second current. An error detection circuit includes a third current generator configured to output a third current responsive to the reference voltage signal and to generate the compensation voltage signal based on the third current. A driver circuit has a first input configured to receive the reference voltage signal and having an output configured to drive the power transistor.

As paths for a current flowing through a conductor, a first current path through which a current flows from a first conductive portion to a second conductive portion, and a second current path through which a current flows from a third conductive portion to the second conductive portion are provided. Each of the first conductive portion, the second conductive portion, and the third conductive portion has a plate shape, a point P1 is located on a plate surface of the first conductive portion, and a point P2 is located on a plate surface of the second conductive portion. A current detecting circuit detects a value related to a potential difference between the points P1 and P2, and outputs a voltage value corresponding to a values of a current flowing through each of the first current path and the second current path.

Methods and apparatus for detecting a zero inductor current to control switch transitions for a power converter. An example method includes outputting a first voltage and a first current, receiving the first voltage and output a second voltage into an input of a comparator, when the second voltage is above a third voltage, outputting a first output voltage, when the second voltage is below the third voltage, outputting a second output voltage, determining when the first current is zero based the output of the comparator, enabling a set of switches based on when the first current is zero.

A semiconductor package is provided, which includes a first die and a second die. The first die includes a first section of a power converter, and the second die includes a second section of the power converter. The power converter may include a plurality of switches, and a Power Management (PM) circuitry to control operation of the power converter by controlling switching of the plurality of switches. The PM circuitry may include a first part and a second part. The first section of the power converter in the first die may include the first part of the PM circuitry, and the second section of the power converter in the second die may include the second part of the PM circuitry.

A motor control system includes a DC-to-DC converter including a semiconductor switch and a reactor that cooperates with the switch to convert input-side DC bus voltage across first and second input-side DC buses into predetermined output-side DC bus voltage across first and second output-side DC buses and to output the output-side voltage, control circuitry that controls duty factor of the switch and determine, based on input-side detection value of the input-side voltage and output-side detection value of the output-side voltage, whether there is failure in the system when the factor is 100 percent and reactor-current detection value of reactor current through the reactor is approximately zero, a smoothing capacitor connected to the output-side buses and disposed between the output-side buses, and an inverter that is connected to the capacitor through the output-side buses, converts DC power from the output-side buses into AC power and supplies the power to a motor.

In accordance with an embodiment, a method of operating a switch-mode power supply includes receiving a measurement of a first current of the switch-mode power supply, determining a ripple of the first current based on the received measurement of the first current, determining a maximum current threshold based on a target average current and the determined ripple of the first current, determining an off time of a switch based on a target current ripple and the determined ripple of the first current, turning off the switch when the first current reaches the maximum current threshold, and turning on the switch after the determined off time has elapsed after turning off the switch.

A multi-phase switch mode, voltage regulator has a transient mode portion in which a phase control output is coupled to one or more control inputs of one or more switch circuits that conduct inductor current through one or more transient phase inductors, from amongst a number of phase inductors. A slew mode control circuit detects a high slope and then a low slope in the feedback voltage and, in between detection of the high slope and the low slope, pulses the phase control output of the transient mode portion so that the switch circuit that conducts transient phase inductor current adds power to, or sinks power from, the power supply output. Other embodiments are also described.