Abstract: In an adaptive leading-edge blanking circuit and method for a switching mode power converter, an inductor current of the converter is sensed and compared with a threshold to decide an end point of a leading-edge blanking time. Circuit and method are further provided for preventing the converter from entering pulse skipping mode, which employs a current trimming circuit in an oscillator for a PWM controller in the converter to reduce a charging current in the oscillator if the output voltage of the converter is excessively high, to thereby reduce the oscillator frequency and in turn lower the switching frequency of a high-side power switch of the converter.

Abstract: An exemplary power supply control circuit (200) includes a first port (201), a second port (202), a third port (203), a controllable switch (280), and a control circuit (270). The first and second ports are configured to receive a power supply voltage signal. The second and third ports are configured to output the power supply voltage signal to a load circuit. The controllable switch includes a control member (281) and a switch member (282). The control circuit is configured to control a working state of the control member. When the load circuit stops working, the control circuit controls the control member to control the switch member to be disconnected, so as to cut off the power supply voltage signal from outputting to the load circuit. A liquid crystal display (400) using the power supply control circuit is also provided.

Abstract: A multiple output AC/DC power adapter is provided. The adapter includes an adapter body with an output connector and more than one output plugs configured for connecting with the output connector. The adapter body includes a DC-DC converting circuit having an input terminal, an output terminal, a first adjustment terminal. The output connector includes a positive terminal, a second adjustment terminal and a negative terminal configured for connecting to the output terminal and the first adjustment terminal of the DC-DC converting circuit and ground correspondingly. The output plugs each includes an adjustment resistor having a resistance value different from the other output plugs. Therefore, when equipped with a plurality of output plugs each of the plurality of plugs having different resistor R0, the adapter can supply different output DC voltages for different electronic device.

Abstract: An exemplary multiplexed direct current regulation output circuit (2) includes a feedback circuit (22), a sampling circuit (30), a power control chip (21), a first output (27), a second output (28), a first half wave rectifier circuit (23), a second half wave rectifier circuit (24), a first filter circuit (25), a second filter circuit (26), a transformer (20), and a balance control circuit (29). The transformer is configured to provide low voltages to the first output via the first half wave rectifier circuit and the first filter circuit in series, and provide high voltages to the second output via the second half wave rectifier circuit and the second filter circuit in series. The balance control circuit is configured to control a voltage at the second output.

Abstract: This invention discloses a power converter with a secondary-side control, including an input circuit with one or more switches, an output circuit with an output end and a controller, and a transformer with a primary-side coil assembly connecting the switch(es) and a secondary-side coil assembly connecting the output circuit. The on/off state of the switch(es) is controlled by variations in voltage of primary-side coil assembly. The controller in the output circuit detects an output voltage and sends detected results to the primary-side coil assembly as a feedback for primary-side coil assembly to regulate the PWM or PFM action of the switch in a specific way to maintain voltage stability.

Abstract: A power supply regulator including a variable current limit threshold that increases during an on time of a switch. In one aspect, a power supply regulator includes a comparator that has a first input coupled to sense a voltage representative of a current flowing through a switch during an on time of the switch. The comparator has a second input coupled to receive a variable current limit threshold that increases during the on time of the switch. A feedback circuit is coupled to receive a feedback signal representative of an output voltage at an output of a power supply. A control circuit is coupled to generate a control signal in response to an output of the comparator and in response to an output of the feedback circuit. The control signal is to be coupled to a control terminal of the switch to control switching of the switch.

Abstract: This invention relates to control techniques and controllers for resonant discontinuous forward power converters (RDFCs). A method of controlling a resonant discontinuous forward converter (RDFC), said converter including a transformer with primary and secondary matched polarity windings and a switch to, in operation, cyclically switch DC power to said primary winding of said transformer, said converter further having a DC output coupled to said secondary winding of said converter, said method comprising: sensing a primary winding signal during an on period of said switch, said primary winding signal representing a current in said primary winding; comparing said sensed primary winding signal with a threshold value; and controlling one or both of an on and off duration of said switch in response to said comparison.

Abstract: The present invention discloses a current mirror circuit generating an output current flowing through an output current path according to an input current flowing through an input current path. The current mirror circuit comprises a P type transistor in the output current path, an operational amplifier, and a basic circuit. The operational amplifier has a negative input coupled to a node receiving the input current, a positive input coupled to a drain of the P type transistor, and an output coupled to a gate of the P type transistor. The basic circuit comprises a first transistor in the input current path and a second transistor in the output current path. The first transistor has a gate and a drain coupled together. The second transistor has a gate coupled to the gate of the first transistor.

Abstract: A combined bandgap generator and temperature sensor for an integrated circuit is disclosed. Embodiments of the invention recognize that bandgap generators typically contain at least one temperature-sensitive element for the purpose of cancelling temperature sensitivity out of the reference voltage the bandgap generator produces. Accordingly, this same temperature-sensitive element is used in accordance with the invention as the means for indicating the temperature of the integrated circuit, without the need to fabricate a temperature sensor separate and apart from the bandgap generator. Specifically, in one embodiment, a voltage across a temperature-sensitive junction from a bandgap generator is assessed in a temperature conversion stage portion of the combined bandgap generator and temperature sensor circuit. Assessment of this voltage can be used to produce a voltage- or current-based output indicative of the temperature of the integrated circuit, which output can be binary or analog in nature.

Abstract: Disclosed a switching power supply circuit of current resonance type including: a switching element; an LC resonance circuit to resonate current flowing through the switching element; and a detection circuit to perform a detection associated with an output current amount on the basis of an operation timing of the switching element and a voltage under resonating operation of the LC resonance circuit.

Abstract: An LED driving circuit can improve characteristics. A first current increasing circuit 10i4 is constituted of a first slow regulating unit 10i41 and a post-stage first supplying circuit 10i43 and, from a point in time of output switching of a first comparator 10i2, that is, when a set temperature exceeding a reference potential Va is attained, gradually increases a temperature compensated current IT1 (?I1) and thereby suppresses the lowering of emission output. Here, by gradually increasing the temperature compensated current IT1 by making use of charging/discharging functions of a capacitor, etc., that is, by increasing the temperature compensated current IT1 over a longer time than a pulse width that a photodetecting element, onto which light from an LED 11 is made incident, can respond within, pulse width distortion and jitter can be suppressed.

Abstract: A control unit includes an input terminal and an output terminal for a signal to be controlled, a control input terminal and a control output terminal for a control signal, variable capacitors connected in a bridge configuration between the input terminal and control input terminal, between the input terminal and control output terminal, between the control input terminal and output terminal, and between the control output terminal and output terminal, capacitances thereof being changed by the control signal, and a differential signal-controlled power source in which the control signal is applied across the control input terminal and control output terminal in a differential mode with a pair of signals having the same absolute value and mutually opposing polarities. Voltage or current of the signal to be controlled is controlled by the control signal changing the capacitances of the variable capacitors in the bridge configuration.

Abstract: A step wave power converter includes a plurality of transformers each configured to receive a Direct Current (DC) voltage from one or more independently generated power sources. Each transformer comprising a primary winding and a secondary winding. A plurality of bridge circuits control different DC voltage inputs from one of the multiple independently generated power sources into the primary windings. One or more processors are configured to use a Phase-Shifted Carrier Pulse Width Modulation (PSCPWM) scheme to operate the bridge circuits in order to produce steps for a step wave Alternating Current (AC) output from the secondary windings.

Abstract: A switching power converter has at least one electronic power switch. To minimize switching losses and optimize efficiency, the gate drive voltage level used to drive the electronic power switch is optimized. In an aspect, a digital controller generates optimizes the gate drive voltage using efficiency optimization algorithms, which in an aspect are programmed in the digital controller. In accordance with an aspect of the present disclosure, the switching power supply has at least two electronic power switches coupled in parallel. Optimization algorithms are used to determine the optimum number of switched electronic power switches that are actively being switched at a given time in order to achieve optimized efficiency for condition changes, such as input voltage variation, load and environmental temperature changes. In an aspect, the algorithms are programmed in a digital controller chip.

Abstract: Present invention belongs to the field of inventers, motor controllers and pulse modulated waveform generation methods and circuits. More specifically it belongs to such methods and circuits utilizing fundamental vectors. This invention features better and more efficient fundamental vectors. The proposed method offers reduced losses, increased efficiency and longer life time of inverters and motor controllers. Better approximation of a three-phase voltage waveform approaching the ideal one is a significant advantage of the proposed method. Another advantage is an easy decomposition of any point of an ideal sinusoidal voltage waveform into the fundamental vectors. This invention is particularly useful for a vector control of asynchronous AC motors.

Abstract: A DC-to-DC converter comprises an error amplifier, a comparator, a PWM controller, a power switch unit, and a control signal monitoring circuit. The PWM controller receives a comparison signal from the comparator and generates a digital control signal that controls the power switch unit such that the DC-to-DC converter supplies a regulated voltage onto a load. The control signal monitoring circuit monitors the digital control signal and detects either a heavy load or a light load condition based on characteristics of the digital control signal. Under the light load condition, the monitoring circuit generates a first enabling signal such that the DC-to-DC controller operates in a power-save mode. Under the heavy load condition, the monitoring circuit generates a second enabling signal such that the DC-to-DC controller operates in a normal operation mode. The DC-to-DC converter consumes substantially less power in the power-save mode than in the normal operation mode.

Abstract: Provided is a switching power supply unit being able to perform voltage conversion between two DC power supplies, and perform appropriate charge operation based on an inputted AC voltage. When a main battery is preferentially charged, an SW control section performs control such that a duty ratio is fixed in switching operation of a switching circuit, and a duty ratio is variable in switching operation of a bidirectional switching circuit. On the other hand, when an accessory battery is preferentially charged, the SW control section performs control such that a duty ratio is variable in switching operation of each of the switching circuit and the bidirectional switching circuit. When the accessory battery is preferentially charged, the SW control section may perform control such that the duty ratio is fixed in switching operation of the switching circuit, and a duty ratio is variable in switching operation of a switching element.

Abstract: A switching circuit for converting an input voltage into an output voltage has an input terminal for receiving the input voltage. A power switching element is coupled to the input terminal and has duty cycle d controllable to adjust the output voltage with respect to a desired level using inductor current representing current in an inductor element connectable to the power switching element. An average and hold circuit is responsive to a voltage at an output of the power switching element to produce an average switch voltage over an ON phase of a switching cycle of the power switching element. A voltage-to-current converter is responsive to the average switch voltage for producing representation of an average inductor current over one or more switching cycles. A current modulator having a duty cycle equal to 1-d modulates the representation of the average inductor current to produce a signal proportional to an average output current of the switching circuit over one or more switching cycles.

Abstract: A heating current used to inductively heat a metallic or magnetic work-piece is generated by an inverter supplied by a supply voltage. The inverter includes four switching elements arranged in an H-bridge circuit having two parallel longitudinal branches and a transverse branch. The switches are controlled so the heating current flows through the transverse branch. The diagonally opposed switching elements are switched from a conductive to a non-conductive state in a temporally staggered manner.

Abstract: A single input pin (48) provides multi-functional features for programming a power supply (10). By connecting the appropriate interface circuit (92, 100, or 112) to the single input pin (48), the power supply (10) is programmed for specific behaviors during power up and toggling of an on/off switch (96, 108). In one mode of operation a light emitting diode (106) in the interface circuit (100) is optically coupled to a microprocessor for signaling the closure of the on/off switch (108), allowing the microprocessor to control the power supply (10) through an opto-coupler (102). In another mode of operation, the single on/off switch (96) controls the power supply (10). In yet another mode of operation, Zener diode (118) in the interface circuit (112) controls the power supply (10) during brown-out and black-out conditions.