Abstract: A sub-threshold low-power and resistor-less reference circuit which is related to the field of reference circuit technology of analog circuit includes a negative-temperature-coefficient voltage generating circuit, a positive-temperature-coefficient voltage generating circuit and a current balancing circuit. The negative-temperature-coefficient voltage generating circuit generates a negative-temperature-coefficient voltage VCTAT based on the negative-temperature voltage characteristic of base-emitter PN junction of the bipolar tsansistor. On the other hand, the positive-temperature-coefficient voltage generating circuit generates a positive-temperature-coefficient voltage VPTAT based on the positive-temperature voltage characteristic of the NMOS transistor operating in a sub-threshold region.

Abstract: A rectifier is described herein. According to one example, the rectifier includes a semiconductor substrate and further includes an anode terminal and a cathode terminal connected by a load current path of a first MOS transistor and a diode that is connected parallel to a load current path. An alternating input voltage is operably applied between the anode terminal and the cathode terminal. Further, the rectifier includes a control circuit that is configured to switch the first MOS transistor on for an on-time period, during which the diode is forward biased. The first MOS transistor, the diode, and the control circuit are integrated in the semiconductor substrate.

Abstract: A transformer unit and a power converter circuit are provided. The transformer unit includes: a first secondary wiring layer including a first secondary winding; a second secondary wiring layer adjacent to the first secondary wiring layer and including a second secondary winding, a first end of the second secondary winding being connected to a first end of the first secondary winding via at least one first via hole; and a plurality of primary wiring layers including a primary winding, the first secondary wiring layer and the second secondary wiring layer being disposed between the plurality of primary wiring layers, wherein at least one of the first via hole is disposed within a projection of the primary winding in the plurality of primary wiring layers.

Abstract: Systems and methods for grounding power generation units with silicon carbide MOSFET power converters are provided. A power generation unit can include a power generator configured to generate multiphase alternating current power at a first voltage. The power generation unit can also include a power converter configured to convert the multiphase alternating current power from the power generator at the first voltage to multiphase alternating current power at a second voltage. The power converter can include one or more silicon carbide MOSFETs and at least one heatsink configured to remove heat from the power converter. The at least one heatsink of the power converter can be electrically connected to a local ground formed by one or more components of the power generation unit.

Abstract: Control ICs for controlling IGBTs include overheat detection comparators that determine an overheated state of the case, in addition to overheat detection comparators that determine an overheated state of chips of the IGBTs. Outputs of the overheat detection comparators are input into an AND circuit, and when all of the overheat detection comparators determine the overheated state of the case, the AND circuit outputs a protection operation signal of high level, and an alarm output circuit outputs an alarm signal. The overheated state of the chips and the overheated state of the case are detected on the basis of chip temperatures measured by temperature detection diodes which are provided with the IGBTs respectively, and therefore a temperature detection IC for case overheat protection is unnecessary, and detection accuracy of the case overheat improves.

Abstract: In a boost chopper circuit, a backflow prevention diode circuit has a withstand voltage equal to or more than a withstand voltage of a capacitor circuit connected in series to the backflow prevention diode circuit between opposite ends of a switching device circuit.

Abstract: A power supply device coupled to a load includes a first switch that switches a current input from an input terminal, a second switch that switches between a ground potential and an output of the first switch, an inductor that establishes a connection between an output terminal and the output of the first switch, a current sensing circuit that senses a peak current value serving as a peak value of a current flowing through the inductor, and a control circuit that controls a first control terminal of the first switch and a second control terminal of the second switch and that calculates a value of an output current flowing through the load, based on an output value of a temporal coefficient circuit coupled to one of a first control signal.

Abstract: A bootstrap circuit applied to a first transistor of a direct-current (DC) to DC converter includes a second transistor, a bootstrapping capacitor and a clamping circuit, wherein the bootstrapping capacitor has a first terminal and a second terminal, and the first terminal is coupled to a source terminal of a transistor, and the source terminal of the second transistor is coupled to the first transistor; and the clamping circuit is coupled between a gate terminal of the second transistor and the second terminal of the bootstrapping capacitor, and is arranged to maintain a voltage drop between the second terminal of the bootstrapping capacitor and the gate terminal of the second transistor. A drain terminal of the second transistor is coupled to a first reference voltage, and a maximum of a voltage level of the gate terminal of the first transistor is greater than the first reference voltage.

Abstract: Provided is a voltage regulator capable of stably generating a constant output voltage even in a high temperature environment. The voltage regulator includes: an output transistor; an output terminal connected to a drain of the output transistor and outputting an output voltage; an error amplifier circuit configured to supply a signal obtained by amplifying a difference between a divided voltage of the output voltage and a reference voltage to a gate of the output transistor; and an NMOS transistor connected between the output terminal and a reference potential and configured to turn on, when the voltage regulator reaches a predetermined temperature at which a leakage current flowing in the output transistor is absorbed, to lead the leakage current to the reference potential.

Abstract: An apparatus is described comprising a bandgap reference circuit comprising: an amplifier including first and second inputs and an output; and a bandgap transistor coupled to the output of the amplifier at a control electrode thereof, the bandgap transistor being further coupled commonly to the first and second inputs of the amplifier at a first electrode thereof to form a feedback path. The apparatus further comprises a resistor coupled to the first electrode of the bandgap transistor.

Abstract: A controller for a switched mode power supply, wherein the controller is configured to be connected to a synchronous rectifier.

Abstract: In one embodiment, a method of over voltage protection control can include: (i) determining whether an output voltage of a buck-boost converter is in an over voltage condition, where the buck-boost converter includes a first switch coupled to an input terminal and an inductor, a second switch coupled to ground and a common node of the first switch and the inductor, a third switch coupled to ground and a common node of a fourth switch and the inductor, where the fourth switch is coupled to an output terminal of the buck-boost converter; and (ii) simultaneously controlling the first, second, third, and fourth switches in the buck-boost converter by turning on the second and third switches, and turning off the first and fourth switches, in response to the over voltage condition.

Abstract: A power supply control method capable of compensating inductance variation of an inductive device in a power supply. The power supply has a power switch controlling a winding current through the inductive device, and converts an input voltage into an output voltage. A sampling time is provided within an ON time of the power switch. The sampling time has a length substantially independent from the ON time, the input voltage, and an inductance of the inductive device. A current-sense signal, a representative of the winding current, is sampled to hold a sample voltage after the sampling time. The power switch is controller in response to the sample voltage so as to make the output voltage comply with an output rating.

Abstract: An inverter apparatus is provided for converting direct current to alternating current. The inverter apparatus includes a boost converter coupled between a power source and a bypass circuit, and a power inverter coupled between the bypass circuit and a load to generate an output voltage. The output voltage is powered by the power source directly via the bypass circuit without activating the boost converter when the output voltage is smaller than a threshold voltage. The output voltage is powered by the power source boosted by the boost converter when the output voltage is larger than the threshold voltage. High efficiency is achieved by bypassed the boost converter.

Abstract: A control method for an active clamp converter has steps of: detecting a state of the load; when the state of the load is a light-load state, using a skipping mode to control a switch frequency of a master switch; when the state of the load is not the light-load state, using an ACF mode to control the switch frequency of the master switch. In the skipping mode, the switch frequency is decreased when the state of the load is getting light, thus providing an energy efficiency power saving function for the light-load state. In the ACF mode, the master switch is controlled to turn on while a reverse current is generated, thus the switching loss of the master switch is reduced.

Abstract: A voltage converter comprises a second controller as a power switch of the secondary side of the transformer for comparing a detection voltage representing an output voltage and/or load current with a first reference voltage and generating a control signal, and a coupling element for transmitting the control signal generated by the second controller to the first controller on the primary side of the transformer enabling the first controller to generate a first pulse signal driving the power switch to control the on/off state of the primary side winding.

Abstract: In accordance with an embodiment, a method includes receiving by a drive circuit electrical power from a voltage tap of a first rectifier circuit that includes a load path and a voltage tap, and using the electrical power by the drive circuit to drive a second rectifier circuit that includes a load path. The load path of the first rectifier circuit and the load path of the second rectifier circuit are coupled to a common circuit node.

Abstract: A control circuit of a switching power-supply device that converts a first DC voltage supplied from an input power source to a second DC voltage, includes: a first A/D converter that converts the second DC voltage into a first digital value, in response to a sampling clock depending on a first sampling clock and a second sampling clock; a control signal generation unit that generates a control signal for controlling on-and-off of the switching element based on of a difference between the first digital value and a target value; a regeneration completion sensing unit that senses completion of regeneration of the inductor and outputs a regeneration completion signal; and a sampling clock generation unit that: generates the first sampling clock, in response to the control signal to turn on the switching element, and generates the second sampling clock, in response to the regeneration completion signal.

Abstract: In one embodiment, a control circuit configured to control a power stage circuit of a primary-controlled flyback converter, can include: (i) a current sense circuit that generates a current sense signal by sampling a primary current; (ii) a voltage sense circuit that generates a voltage sense signal by sampling an auxiliary voltage after a blanking time has elapsed; (iii) a control signal generator that generates a switch control signal according to the voltage sense signal and the current sense signal; and (iv) the switch control signal being configured to control a power switch of the power stage circuit, where the switch control signal is active during a constant on time.

Abstract: A voltage regulator provides an output current at an output voltage, based on an input voltage. The voltage regulator has a pass transistor for deriving the output current. The voltage regulator contains a drive transistor forming a current mirror in conjunction with the pass transistor, such that the output current through the pass transistor is dependent on a drive current through the drive transistor. The voltage regulator comprises an auxiliary transistor arranged such that at least a fraction of the drive current through the drive transistor flows through the auxiliary transistor. The voltage regulator has amplification circuitry to set the drive current through the drive transistor depending on the output voltage and on a reference voltage. The voltage regulator further contains control circuitry to detect an indication for a dropout situation where a difference between the input voltage and the output voltage falls below a dropout voltage.