Abstract: A switch controller compensates the total on-time delay of the switch in a switching power converter. The intended on-time of the switching transistor for the present switching cycle is reduced by the time difference between the actual on-time and the intended on-time of the switching transistor in the previous switching cycle in the switching power converter. The total delay of the switch in the switching power converter, including propagation delay, switch turn-on delay, and switch turn-off delay, can be compensated in real time, cycle by cycle.

Abstract: A control circuit for a switching DC/DC Converter comprising: an input for an indicator signal indicative of an output current level from said converter; a peak detector for detecting and storing a maximum value of said indicator signal; a comparator element for comparing an instantaneous value of said indicator signal with said stored maximum value, and for generating a switching signal when said instantaneous value becomes less than a predetermined fraction of said stored value; reinitializer means for reinitializing said peak detector in response to said switching signal; and means for generating a control signal that switches between a state in which it increases over time and a state in which it decreases over time in response to said switching signal. A control module for photovoltaic generator, the module including such a control circuit, and a photovoltaic generator system comprising a plurality of such modules, each controlling a respective photovoltaic generator.

Abstract: A switching power supply device has a drive circuit that can minimize a loss while being compact. The drive circuit turns on and off a high-side switching element (MOSFET) according to a positive or negative voltage developed at a tertiary winding of a transformer. The drive circuit includes a control unit that detects the development time, during which the negative voltage is developed at the tertiary winding, as the on time of a low-side switching element, and makes the on time of the high-side switching element nearly or substantially equal to the development time.

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 transformer signal, said transformer signal representing a voltage across a winding of said transformer or a resonant current in a winding of said transformer; calculating a resonance period of said RDFC from said sensed transformer signal; and controlling an off duration of said switch in response to said calculated resonance period such that a sub-harmonic oscillation in said resonant voltage across said primary winding is reduced.

Abstract: A quick response switching regulator comprises a power stage having a pair of high-side switch and low-side switch and an inductor connected together by a switching node, a feedback circuit for producing a feedback signal, and a control circuit producing control signals with reference to the feedback signal to control the pair of high-side switch and low-side switch. The feedback circuit is connected to the switching node to shorten the feedback path and speed up the response. The control circuit further monitors the current flowing through the inductor to keep the low-side switch off before the peak of the inductor current becomes higher than a value.

Abstract: A stabilizing method for a current source is provided. The current source is provided a current which increases when temperature rises. An adjustment circuit provides an input current increasing when temperature rises. A rising ratio of the input current with temperature is the same as a rising ratio of the current of the current source with temperature. The current of the current source is subtracted from the input current. After the current of the current source is subtracted from the input current, the current of the current source does not vary when temperature varies.

Abstract: An analog control circuit is coupled to an apparatus having a variable characteristic over an operating range. A sensing circuit is coupled to the apparatus and the control circuit during the range of operation of the apparatus and is operative to sense the variable characteristic. The operating parameter of the apparatus is controlled to be set at a level corresponding to a prescribed criterion, which may be a maximum or minimum, of the characteristic sensed over the range of operation.

Abstract: A negative potential discharge circuit may include an internal voltage generating circuit and/or a discharge unit. The internal voltage generating circuit may be configured to generate a regulated output voltage based on a power supply voltage. The discharge unit may be configured to discharge a negative potential using the regulated output voltage. A method of discharging a negative potential may include generating a regulated output voltage based on a power supply voltage, and/or discharging a negative potential using the regulated output voltage.

Abstract: A self-tracking analog-to-digital converter includes a digital-to-analog converter (DAC) adapted to provide a variable reference voltage, a windowed flash analog-to-digital converter (ADC) adapted to provide an error signal ek corresponding to a difference between an input voltage Vi and the variable reference voltage, and digital circuitry adapted to generate suitable control signals for the DAC based on the error signal ek. More particularly, the digital circuitry includes a first digital circuit adapted to provide a first function value f(ek) in response to the error signal ek, the first function value f(ek) representing an amount of correction to be applied to the variable reference voltage. A second digital circuit is adapted to provide a counter that combines the first function value f(ek) with a previous counter state Nk to provide a next counter state Nk+1, the next counter state Nk+1 being applied as an input to the digital-to-analog converter.

Abstract: A razor includes a load and a voltage conversion system coupled to a voltage source and the load for transforming a variable voltage provided by the voltage source into a constant operating voltage for driving a load.

Abstract: An alternator tester is provided for testing an alternator of a vehicle while the alternator is coupled to the vehicle. A sensor is configured to couple to the vehicle and sense a signal related to operation of the alternator. A memory contains data related to operator instructions for performing an alternator tester of a function of vehicle type. A processor configured to provide an output indication of alternator condition based upon the sensed signal. An extra load or connection can be provided for coupling to the electrical system.

Abstract: The present invention provides a three-level ac generating circuit and the control method thereof. The three-level ac generating circuit includes a three-level boosting circuit connected to an input source and including a positive boosting portion and a negative boosting portion; and a three-level inverting circuit connected to the three-level boosting circuit and including a positive inverting portion and a negative inverting portion, wherein while the input source is a relative low voltage, the relatively low voltage is boosted via the three-level boosting circuit, inverted and output via the three-level inverting circuit; while the input source is a relatively high voltage, the relatively high voltage is inverted and output via the three-level inverting circuit and wherein the output of the three-level ac generating circuit is power grid.

Abstract: System and method for providing switching to power regulators. According to an embodiment, the present invention provides system for providing switching. The system includes a first voltage supply that is configured to provide a first voltage. The system also includes a second voltage supply that is configured to provide a second voltage. The second voltage being independent from the first voltage. The system additionally includes a controller component that is electrically coupled to the first voltage supply. For example, the controller component being configured to receive at least a first input signal and to provide at least a first output signal. Additionally, the system includes a gate driver component that is electrically coupled to the second voltage supply. The gate driver component is configured to receive at least the first output signal and generated a second output signal in response to at least the second voltage and the first output signal.

Abstract: An exemplary embodiment includes a method for balancing thyristor bridge circuits, the method comprising, determining currents of thyristors in a first leg of thyristors of a thyristor bridge circuit, determining a first set of gate firing times for the thyristors in the first leg of thyristors responsive to determining the current of the thyristors in the first gate of thyristors, wherein the first set of gate firing times are operative to balance a current load between the thyristors in the first leg of thyristors, and gating the thyristors in the first leg of thyristors according to the first set of gate firing times.

Abstract: A synchronous rectification switching regulator, and a control circuit and a control method for controlling the synchronous rectification switching regulator. The regulator includes an output terminal, a first switching device, an inductor, a second switching device for synchronous rectification, a control circuit unit to control switching of the first switching device and cause the second switching device to perform switching opposite to that of the first switching device, and a reverse current detection circuit unit to detect a generation or an indication of a reverse current flowing from the output terminal to the second switching device and make the control circuit unit turn off the second switching device when a generation or an indication of the reverse current is detected. The reverse current detection circuit unit stops detecting a generation or an indication of the reverse current while the second switching device is turned off by the control circuit unit.

Abstract: A synchronous rectifying circuit is provided for resonant power converter. An integrated synchronous rectifier comprises a rectifying terminal, a ground terminal a first input terminal and a second input terminal. The rectifying terminal is coupled to the secondary side of a power transformer. The ground terminal is coupled to the output of the power converter. A power transistor is connected between the rectifying terminal and the ground terminal. The first input terminal and the second input terminal are coupled to receive a pulse signal for turning on/off the power transistor. A pulse-signal generation circuit includes an input circuit coupled to receive the switching signal for switching the power transformer of the power converter.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: An electronic device includes: an integrated circuit having a first circuit part, a second circuit part, a first power source line of the first circuit part, a second power source line of the second circuit part, and a coupling switch coupling the first power source line and the second power source line; a power source supply part which generates a power source to be supplied to the first and second circuit parts and which has a power source supply control circuit controlling the supply of power source to the second circuit part; and a power source control part that controls the power source supply control circuit and the coupling switch, wherein the power source control part controls the power source supply control circuit so as to supply a power source in accordance with the operating state of the second circuit part and closes the coupling switch.

Abstract: A method, apparatus, and system for controlling the voltage levels across capacitors coupled between a first node and a second node of an integrated circuit so that the voltage levels across these capacitors will not exceed the breakdown voltage limitation of these capacitors. The voltage level between the first and second nodes of the integrated circuit can vary from a second voltage level to a first voltage level when the integrated circuit transitions from a second power state to a first power state, respectively. A first capacitor and a second capacitor are connected in series between the first and second nodes of the integrated circuit forming a middle node between the first and second capacitors.

Abstract: A structure for protecting and guiding a flat cable connected between a traveling module and a protective cover of a scanner is disclosed. The protective structure includes an anti-bending member mounted onto the traveling module for preventing the flat cable from being over-bent at its first end. A guide channel member is disposed on the protective cover under the flat cable and along the moving direction of the traveling module for guiding the flat cable during moving of the traveling module and preventing the flat cable from being swung left and right. The second end of the flat cable is extended into the protective cover via a protective sheath fitted on the cover for preventing the second end of the flat cable from excess bending angle and keep the flat cable smoothly moving without deflection.