Abstract: A switching power supply includes: a switching output circuit generating an output voltage from an input voltage according to ON/OFF control of an output transistor by a pulse width modulation (PWM) signal; a first voltage generating circuit generating a first voltage based on a difference between the output voltage and a predetermined reference voltage; a second voltage generating circuit generating a triangular second voltage; a comparing circuit generating a comparison signal by comparing the first voltage and the second voltage; a clock oscillating circuit generating a clock signal; and a logic circuit generating a PWM signal in response to the clock signal and the comparison signal, wherein the second voltage generating circuit generates the second voltage by adding a first slope voltage having a first slope and a second slope voltage having a second slope according to current flown through the switching output circuit.

Abstract: Features and advantages of the present disclosure include a switching regulator and current measurement circuit. In one embodiment, a switching transistor in the switching regulator has a first voltage on a first terminal and a switching voltage on a second terminal. A current measurement circuit has first and second input terminals. A first switch couples the second terminal of the switching transistor to the first terminal of the current measurement circuit when the switching transistor is on, where the second input terminal of the current measurement circuit is coupled to the first terminal of the switching transistor and measurement(s) may be taken. When the switching transistor is off, the first and second input terminals of the current measurement circuit are coupled together, and measurements emulate zero current through the switching transistor.

Abstract: A switching power source apparatus includes: a switching output circuit that generates an output voltage from an input voltage; an error amplifier that generates an error voltage in accordance with a difference between a predetermined reference voltage and the output voltage or a feedback voltage corresponding to the output voltage; a clock signal generation circuit that generates a clock signal; a slope voltage generation circuit that receives the clock signal to generate a slope voltage; a delay circuit that delays the clock signal to generate an on-signal; a PWM comparator that compares the error voltage and the slope voltage with each other to generate an off-signal; a logic circuit that receives the on-signal and off-signal to generate a pulse width modulation signal; and a switch drive circuit that receives the pulse width modulation signal to generate a drive signal for the switching output circuit.

Abstract: A power conversion apparatus and a protection method of the power conversion apparatus while a feedback current signal of the power conversion apparatus is abnormal are provided. The protection method includes a step of stopping switching a power switch if a duty cycle of a pulse width modulation signal is continuously greater than a preset duty cycle for at least one signal cycle and a voltage of a current sensing signal is smaller than a preset voltage level during the at least one signal cycle.

Abstract: Light-load control devices and methods implemented in applications such as voltage converters. In some embodiments, a control system for a voltage converter can be configured to determine whether the voltage converter is in a first load state such as a light-load state. The control system can be further configured to generate a first driving signal when the voltage converter is in the light-load state. The control system can be further configured to route the first driving signal to a control element of the voltage converter when the voltage converter is in the light-load state, and to route a second driving signal to the control element when the voltage converter is in a second load state such as a heavier-load state. Such a control system can yield reduced power consumption of the control element when the voltage converter is in the light-load state.

Abstract: In High Voltage CMOS technologies the supply voltage is typically higher than the maximum allowed gate voltage. In a switching output stage of amplifiers such class-D amplifiers and DC-DC converters the gates of the power field effect transistors need to be charged quickly. This requires a gate driver that is capable of delivering large currents without exceeding the maximum allowed voltage on the gate of the power field effect transistors.

Abstract: A voltage regulation system includes a voltage regulator configured to output a control signal indicating whether a voltage based on output of the voltage regulator is lower than a specified value. A charge pump is configured to output a voltage and a charging current. A pump monitor is configured to receive the control signal and the output voltage of the charge pump, and activate the charge pump when the control signal indicates the voltage based on output of the voltage regulator is lower than a specified value and the output voltage of the charge pump is lower than a threshold value.

Abstract: A power circuit includes an input terminal to which an input voltage is applied; a control element which generates an output voltage obtained by regulating the input voltage; an output terminal from which the output voltage is output; a discharge circuit which discharges by extracting an electric charge from the control element on a side of the output terminal; a drive circuit which generates a drive current for causing the discharge circuit to operate using power of the control element on the side of the input terminal; a detection circuit which detects the output voltage; and a discharge control circuit which decreases a current value of the drive current to a current value enabling the discharge circuit to continuously operate in a case where the detection circuit detects that the output voltage reaches a setup voltage by an operation of the discharge circuit.

Abstract: A peak cut power calculation unit calculates peak cut power transmittable to an overhead wire as power exhibiting monotonic non-increase with respect to a resistance value of the overhead wire between a vehicle and a substation. In addition, a peak cut unit controls electrical charging/discharging of a rechargeable battery with power of a difference between load power and transmission peak cut power when the load power is equal to or more than the peak cut power.

Abstract: A solar energy utilization system includes a solar panel, a motor driven by an inverter circuit functioning as a motor drive circuit with power output by the solar panel, a solar output voltage monitor functioning as a monitor that monitors an input or an output of the solar panel and also functioning as a monitor that monitors an input or an output of the inverter circuit, and a controller. The controller has a control mode in which the inverter circuit is controlled such that an output voltage of the solar panel is maintained at a voltage higher than a maximum power point voltage. In this control mode, the controller performs the control such that a rotation speed of the motor is changed repeatedly at predetermined timings.

Abstract: In one embodiment, a light-emitting diode (LED) driver can include: (i) a reference voltage control circuit configured to provide a reference voltage signal in response to an enable signal; (ii) a current control circuit configured to control an output current of the LED driver in response to the reference voltage signal; and (iii) the LED driver being configured to drive an LED load when the enable signal is active.

Abstract: The magnitude of an output current that flows into a load is determined by placing a sense bipolar transistor and a sense resistor in series with the load, utilizing the non-linear current characteristics of the base-emitter junction of the sense bipolar transistor to compress and sense an emitter current logarithmically, and then performing an inverse log function to determine the emitter current, which is substantially identical to the output current that flows into the load.

Abstract: Systems, circuits, devices and methods related to voltage converters. In some embodiments, a control system for a voltage converter can include a driving unit configured to generate a driving signal having a pulse width and a frequency. The driving signal is provided to a voltage conversion circuit to control conversion of an input voltage into an output voltage. The control system can further include a modulation unit configured to modulate the pulse width of the driving signal based on the output voltage to thereby allow adjustment of the output voltage. The control system can further include a control circuit configured to adjust the frequency of the driving signal based on the modulated pulse width. Such a control system can be useful in situations such as when the output voltage is close to the input voltage, or when a load being driven by the output voltage is relatively low.

Abstract: A voltage converter includes a converter circuit and a control circuit coupled to the converter circuit and configured to selectively operate the converter circuit in a boost mode or a floating buck mode in response to a level of an input voltage supplied to the voltage converter circuit. The converter circuit may further include an inductor, a first control switch coupled to the control circuit, and a second control switch coupled to the control circuit. The control circuit may be configured to control a state of the first control switch in the boost mode in response to a level of current in the inductor, and the control circuit may be configured to control a state of the second control switch in the floating buck mode in response to the level of current in the inductor.

Abstract: A switching power supply device includes a switching control circuit that generates a switching control signal such that a desired output voltage is generated from an input voltage, a drive circuit that turns on/off an output transistor in accordance with the switching control signal, and an on-pulse stop circuit that generates a pulse stop signal such that the number of ON pulses of the switching control signal is reduced in a state where a load is heavier than a first threshold but is lighter than a second threshold.

Abstract: Control circuitry for controlling a spa water heater, wherein a microcontroller is configured to detect zero crossings of an A.C. line voltage from a voltage sense signal, to cause closing of a first heater relay and a second heater relay, to detect the time at which heater current is initially sensed by a current sensor after the initial closing of the second heater relay, to measure a time delay between the time that the second heater relay is closed and the time at which heater current is initially sensed, and to adjust the time at which a second closing of the second heater relay occurs such that zero crossings of the heater current occur at the same time as zero crossings of the voltage waveform. The control circuitry further includes a voltage sense circuit comprising a first diode connected in series with a current limiting resistance connected in series with a Zener diode, which is in turn connected in series with an optical coupler LED.

Abstract: Methods and systems to regulate a voltage with multiple selectable voltage regulator (VR) modes, using multiple corresponding circuits and/or a configurable circuit. The circuit may be configurable for one or more of a power-gate VR mode, a switched-capacitor VR (SCVR) mode, and a linear mode, such as a low drop-out (LDO) VR mode. A feedback controller, such as a proportional-integral-derivative (PID) controller, may configure and/or control a multi-mode VR for a selected VR mode. The feedback controller may select a VR mode based on a reference voltage and voltage ranges associated with the VR modes. The circuit may be configurable as banks of VRs, and the controller may be implemented to transition between VR modes by switching sub-banks between modes until the transition is complete.

Abstract: A COT switching converter includes a first switch, a second switch, an inductor, an on-time control circuit configured to generate an on-time control signal, a ramp compensation generator configured to generate a compensation signal, a comparing circuit, a logic circuit, a driving circuit and a feed forward circuit configured to generate a compensation control signal based on the input voltage of the switching circuit. The comparing circuit compares the sum of the compensation signal and a feedback signal with a reference signal to generate a comparison signal. Based on the on-time control signal and the comparison signal, the logic circuit generates a control signal with a duty cycle to drive the first and second switches through the driving circuit.

Abstract: A feedback signal stabilized by a capacitor and related to an output voltage of a power converter is used to acquire the output power information of the power converter, and a control circuit uses a second clock not related to the switching frequency of the power converter to count a duration time of the feedback signal being higher than a threshold. When the duration time is higher than a preset time, an abnormal output power of the power converter is distinguished and the power converter will be turned off. The feedback signal will not vary severely even if the output terminal of the power converter is interfered, and the counted duration time will not be influenced when the switching frequency is changing caused by a load changing.

Abstract: Techniques are described for controlling an amount of current flowing through one or more light-emitting-diodes (LEDs), without sensing input and/or output voltage, so that the amount of current flowing through the one or more LEDs is approximately equal to a target current level. The techniques provide for coarse and fine tuning of the amount of time a transistor, through which the current flows, is turned on to control the amount of current flowing through the one or more LEDs.

Abstract: A resonant converter includes a first switch coupled between a first node and a primary side ground, a second switch coupled between an input voltage and the first node, at least one capacitor and at least one inductor coupled in series between both ends of the first switch, and a switch control circuit that shifts switching frequencies of the first and second switches during a period for which an abnormal event lasts when occurrence of the abnormal event is detected, and shifts the switching frequencies in an opposite direction when the abnormal event ends.

Abstract: According to one embodiment, a semiconductor device includes: a first switching element comprising a heterojunction comprising a first compound semiconductor layer and a second compound semiconductor layer; and a driver which applies a voltage to a gate of the first switching element to control turn-on and turn-off of the first switching element. The driver temporarily increases a gate voltage of the first switching element at a timing when the first switching element is turned on, during a period while the first switching element is on.

Abstract: An amplitude normalization circuit includes: a peak detector that detects a peak value of a full-wave rectified voltage of an AC voltage; a triangular wave oscillator connected to the peak detector generates a triangular wave voltage having the peak value; a comparator connected to the triangular oscillator compares the triangular wave voltage with the full-wave rectified voltage and outputs a pulse width modulation signal; and a waveform converter connected to the comparator converts a waveform of the pulse width modulation signal and outputs an output voltage with constant amplitude.

Abstract: A switching regulator control circuit comprises a first control circuit to control conduction of the switch according to a first mode of operation and having a regulation point and a second control circuit to control conduction of the switch according to a second mode of operation in response to a reference signal that is calibrated to have a predetermined relationship with respect to the regulation point of the first control circuit. In some embodiments, the reference signal is calibrated to be a predetermined amount greater than the regulation point of the first control circuit and may be calibrated during the first mode of operation or in response to a regulator start or restart event.

Abstract: A method for controlling converter such as a Flyback converter is disclosed. A load of the Flyback converter varies between zero and a peak value. The method includes: a load detecting step for detecting the load; and an operating mode control step for controlling the Flyback converter to switch between two or more of a continuous conduction mode, a valley conduction mode and a burst mode according to the load. A converter such as a Flyback converter is also provided.

Abstract: A semiconductor integrated circuit that is used for a stabilizing power supply circuit which supplies an output power supply voltage to a parallel connection of a smoothing capacitor and a load, from an input power supply voltage, includes an error amplifier that detects an error of the output power supply voltage, an output control circuit that is connected between the input terminal and the output terminal, a phase compensation circuit that is connected to the error amplifier, and a detection control circuit that is connected to the phase compensation circuit.

Abstract: A switching converter has an input port for receiving an input voltage and an output port for providing an output voltage. The switching converter has a power stage, an energy stored circuit, a power conversion circuit and a control circuit. The power stage has an input terminal coupled to the input port and an output terminal coupled to the output port. The energy stored circuit is charged by the input voltage and provides a first bias voltage which maintains a predetermined time period after the input voltage is less than a predetermined voltage level. The power conversion circuit provides a second bias voltage. The control circuit provides a control signal to control the power stage and discharges the output voltage based on a discharge control signal, wherein the control circuit is powered by either the first bias voltage or the second bias voltage.

Abstract: A controller for use in a power converter includes a gate drive circuit coupled to generate a control signal to switch a power switch of the power converter. A zero current detection circuit is coupled to a multifunction pin coupled to receive a multifunction signal that is representative of an input voltage of the power converter when the power switch is on, and representative of an output voltage of the power converter when the power switch is off. The zero current detection circuit is coupled to generate a zero current detection signal. An overvoltage detection circuit is coupled to receive the multifunction signal and a state signal representative of a state of the power switch to generate in response to the state signal and the multifunction signal a line overvoltage signal and an output over voltage signal coupled to be received by the gate drive circuit.

Abstract: In one implementation, a voltage boost assembly including a boost converter having a capacitive element arranged at an output, and an inductive element connectable to an electrical supply. The voltage boost assembly also includes a sensor assembly provided to generate a quick-start enable signal in response to detecting that an electrical condition relative to an electrical output of the boost converter has breached a first threshold. The voltage boost assembly further includes a quick-start module responsive to the quick-start enable signal, and configured to drive the boost converter at a relatively high duty-cycle and so that the boost converter delivers an output current that satisfies a second threshold in order to charge the capacitive element arranged at the output.

Abstract: A bi-directional switch that includes a first terminal, a second terminal, and a plurality of ballast circuits is provided. Each ballast circuit includes a first metal-oxide-semiconductor field-effect transistor (MOSFET) comprising a first input connector, a first output connector, a first body, and a first body diode, and a second MOSFET comprising a second input connector, a second output connector, a second body, and a second body diode. Each first input connector is coupled to the first terminal, each second input connector is coupled to the second terminal, and each first output connector is coupled only to the second output connector of the second MOSFET that is in a same ballast circuit.

Abstract: A method for controlling a polyphase inverter that includes a number of half bridges connected into an intermediate voltage circuit and center taps between switching elements. By cyclically switching the switching elements, the respective center taps of the half bridges are connected to an upper intermediate circuit rail or to a lower intermediate circuit rail of the intermediate voltage circuit according to the principle of pulse width modulation. The switching elements of at least one half bridge are driven in a modified manner, at least in some time intervals, in that the switching pulses of at least two consecutive periods of the pulse width modulation are concatenated directly in time as one switching pulse. In this way, the switching frequencies of the correspondingly driven switching elements and thus the switching losses of the latter can be further reduced.

Abstract: Boost-type switch-mode rectifiers (SMR) commonly use a resistor or a magnetic current sensor to measure the instantaneous input or inductor current that is used as the feedback to the current controller. A novel current sensorless scheme is described that computes the inductor current from the measured inductor voltage in a single-phase boost-type SMR using an adaptive low pass filter. This calculation requires an estimate of the inductance and the equivalent series resistance of the inductor coil. Both these parameters are dependent on operating conditions and are updated continuously. This is done using an adaptive model of the inductor that computes these parameters of the inductor once in every half cycle of the input current. The adaptation scheme is robust against parameter variations. Simulation and experimental results confirm the effectiveness of the proposed technique which provides comparable performance to standard measured feedback current scheme both under steady-state and transient conditions.

Abstract: A controller for controlling operation of a switching regulator including a modulator, a discontinuous conduction mode (DCM) controller, an audible DCM (ADCM) controller, and a sub-sonic discontinuous conduction mode (SBDCM) controller. The modulator generally operates in a continuous conduction mode. The DCM controller modifies operation to DCM during low loads. The ADCM controller detects when the switching frequency is less than a super-sonic frequency threshold and modifies operation to maintain the switching frequency at a super-sonic frequency level. The SBDCM controller detects a sub-sonic operating condition during ADCM operation and responsively inhibits operation of the ADCM mode controller to allow a SBDCM mode within a sub-sonic switching frequency range. The SBDCM operating mode allows for efficient connected standby operation. The SBDCM controller allows operation to return to other modes when the switching frequency increases above the sub-sonic level.

Abstract: A DC-DC converter includes: a converter including a first transistor, a second transistor and an inductor; a first gate driver and a second gate driver configured to respectively control the first and second transistors; a pulse width modulation (PWM) control circuit configured to output a PWM signal to the first gate driver and a first logic circuit, the first logic circuit configured to receive the PWM signal and a second logic signal, and to output a first logic signal to the second gate driver; and a second logic circuit configured to receive a first control signal and a second control signal, and to output the second logic signal to the first logic circuit.

Abstract: A control circuit operable to control the switching of switching elements in a switched mode power supply. The control circuit comprises a switching control signal generator operable to generate control signals for switching the switching elements such that the switched mode power supply converts an input voltage (Vin) to an output voltage Vout). The control circuit further comprises an operation mode setting module which is operable to receive a signal (I) indicative of a current flowing to a load that is connected to an output of the switched mode power supply, and operable to cause the switching control signal generator to generate the control signals so as to operate the switched mode power supply in a continuous conduction mode or a pulse skipping mode in dependence upon the current.

Abstract: The present invention provides a constant on time controller packaged in one single package for controlling a buck converting circuit to convert an input voltage into an output voltage. The constant on time controller includes an input voltage detecting circuit, an on-time determining circuit and a driving circuit. The input voltage detecting circuit receives a bootstrap voltage to generate an input voltage detecting signal indicative of the input voltage. The on-time determining circuit receives the input voltage detecting signal and generates an on-time signal in response to the input voltage detecting signal and the output voltage. The driving circuit controls the buck converting circuit according to the n-time signal.

Abstract: A device and method for operating a switching power converter are disclosed. In an embodiment a circuit includes a switching power converter having a half bridge including a high-side semiconductor switch connected to a low-side semiconductor switch and an inductor coupled to a half-bridge output node. The circuit further includes a control circuit configured to generate drive signals to switch the high-side semiconductor switch and the low-side semiconductor switch on and off, wherein the drive signals are generated to ensure a dead time between a switch-off of the low-side switch and a subsequent switch-on of the high side switch, and wherein the dead time is set to a first value, when an inductor current is negative at a time of switching, and the dead time is set to a second value, which is lower than the first value, when the inductor current is positive at the time of switching.

Abstract: A switching control circuit includes driving a flow of direct current through an at least partially inductive load. The switching control circuit is adapted for adjusting a control current in order to activate and/or deactivate a flow of current to a load terminal. The system comprises a timer element for initiating at least one timed adjustment of the control current during activation or deactivation of the flow of current through a first semiconductor switch of the circuit so as to anticipate a state change of a component of the switching control circuit. The controller is adapted for determining a timing for the timed adjustment in a predictive manner. A method employs the various features of the switching control circuit.

Abstract: A power converter includes a first stage voltage modulator configured to receive an input voltage and provide a modulated voltage. A second stage power converter is configured to receive the modulated voltage and vary a switching frequency of the second stage power converter in accordance with the modulated voltage to provide an output voltage.

Abstract: In a current mode switching power supply, current through the inductor needs to be sensed to control the peak current. The inductor current includes a DC component and an AC component containing switching noise. To reduce the switching noise, the actual inductor current is sensed to generate a signal, and a first AC component is attenuated by a first RC circuit while not attenuating a first DC component. A second AC component is derived by applying the rectangular wave switch voltage, which is at the duty cycle of the regulator, to a second RC filter, which blocks a second DC component. The second AC component is much larger than the first AC component and does not contain switching noise. The large second AC component, the smaller “noisy” first AC component, and the first DC component are applied to the first RC circuit to create a low-noise inductor current signal.

Abstract: When generating a voltage Vout of a DC-to-DC converter for a load which is connected to the converter, it is necessary to monitor the quality of the voltage, in particular its amplitude. For this, provision is made for a comparator to be arranged between the output of the DC-to-DC converter and a control input of the control unit, with a first input of the comparator being connected to the output of the DC-to-DC converter (Vout), the second input of the comparator being connected to a reference voltage (Vrestore) and the output of the comparator being connected to the control input of the control unit of the DC-to-DC converter, for controlling the voltage Vout.

Abstract: A power supply system for maintaining the efficiency of an AC/DC power conversion unit in relation to a load is disclosed. The load varies in response to power usage during operation of the power supply system. An AC power input and a DC power output of the power conversion unit direct DC power to attached components. A master controller disposed in the power supply system detects the load of an attached computer system through a DC meter and executes an algorithm to determine the values of circuit parameters of conversion circuits in the AC/DC power conversion unit. The master controller sends the values to a mode controller through a digital signal interface. The mode controller adjusts the operating mode of the conversion circuits and thus changes the efficiency of the AC/DC power conversion unit.

Abstract: A switched-mode power supply in a set of parallel-connected switched-mode power supplies is operated to (1) monitor both output current and operating temperature, and (2) auto-tune an output voltage using two-dimensional control that employs a two-dimensional function of the output current and the operating temperature. The two-dimensional function is a sharing function whose use in each of the supplies effects a coordinated sharing of both load current and operating temperature across the set of supplies. Temperature sharing includes monitoring and controlling distribution of operating temperatures across the set of supplies to reduce undesirable temperature imbalance that can cause excessive thermal stress and reduce reliability.

Abstract: The present disclosure relates to methods, a system and a module for operating a power converter module. The power converter module comprises a voltage converter, an output circuitry, and a processing circuitry operable for controlling the voltage converter. One method comprises transmitting a first status signal representing operating parameters of the voltage converter to the processing circuitry. Determining whether the first status signal of the voltage converter is acceptable. The method also comprises transmitting a second status signal representing the operating parameters of the output circuitry to the processing circuitry. The method also comprises determining if the second status signal is above a predetermined threshold value. When the second status signal is above said predetermined threshold value and the status of the voltage converter is acceptable, entering a peak output mode operating the voltage converter at maximum power dissipation.

Abstract: A constant ON-time or constant OFF-time switching power converter includes a control circuit for controlling a power switch. The control circuit includes: a constant ON-time or constant OFF-time calculation circuit, for calculating a constant ON-time or constant OFF-time; a logic circuit having inputs for receiving an output of the constant ON-time or constant OFF-time calculation circuit and a clock signal, respectively, wherein the clock signal has a frequency which is the desired fixed frequency; and a flip-flop for generating an output signal according to a set input and a reset input, wherein one of the set input and the reset input receives an output of the logic circuit, and the other one of the set input and the reset input receives a trigger signal which determines a start time of the ON-time or OFF-time.

Abstract: A power conversion circuit includes a voltage boost circuit including a boost inductor configured to generate an output voltage in response to an input voltage, and a boost controller configured to control operation of the voltage boost circuit. The boost controller is configured to control operation of the voltage boost circuit in response to a level of current in the boost inductor.

Abstract: Provided is a DC/DC converter capable of immediately resuming to a normal operation from a state in which an output transistor is continued to be turned off when a reverse current is generated in a light load state. The DC/DC converter includes an ON-timer circuit including: a ripple generation circuit; a smoothing circuit; a timer circuit configured to output an ON-time signal; a logic circuit configured to detect a sign of generation of a reverse current; and a switch circuit configured to, based on a detection signal of the logic circuit, maintain an output voltage of the ripple generation circuit or control the output voltage of the ripple generation circuit to a predetermined voltage.

Abstract: Methods and apparatuses for providing a solution for incompatibility between nonsinusoidal waveform uninterruptible power supply (UPS) systems and active power factor correction (PFC) loads are disclosed. An embodiment of the invention includes generating a nonsinusoidal signal waveform (e.g., a voltage waveform), to be delivered to the load, with a pulse width modulation (PWM) duty width, sampling the nonsinusoidal signal waveform to collect output signal samples, and adjusting the duty width to control the nonsinusoidal signal waveform as a function of the output signal samples to deliver a desired signal characteristic (e.g., RMS signal level) to the load. In embodiments of the invention, the output duty width is adjusted differently in cases of rising and falling power consumption, respectively, by the load.

Abstract: A switching element drive circuit of the present invention outputs a voltage to the switching element by use of a voltage output unit configured as an amplifier circuit having a voltage amplification factor of 1 to drive the switching element. When the switching element is turned on, a turn-on voltage having a value higher than a threshold voltage of the switching element and lower than a value of a voltage of a power supply of the switching element drive circuit is provided to the voltage output unit. After elapse of a turn-on voltage maintenance period, a voltage provided to the voltage output unit is switched by a voltage switching unit to the voltage of the power supply of the switching element drive circuit.

Abstract: A DC to DC converter circuit includes circuitry for generating a PWM waveform signal at a phase node of a DC to DC converter responsive to an input voltage and a monitor monitored output voltage. The circuitry further includes a high side switching transistor connected between the input voltage and a phase node and a low side switching transistor connected between the phase node and ground. An output filter is connected to the circuitry for generating the PWM waveform signal. The output filter includes an inductor having a first side connected to the phase node and a second side connected to an output voltage node. Detection circuitry detects zero current crossings in the inductor responsive to a voltage across the high side switching transistor and a voltage across the low side switching transistor.