Abstract: A method, device, and plurality of circuit enhancements for a rectifier system that enable reduction in lower order and higher order harmonics, without substantially reducing the rectifier's direct current output voltage. The rectifier system comprises a phase shifting primary transformer subsystem and a multi-pulse rectifier. At least one series impedance path is coupled to one of three input terminals/leads of the transformer subsystem and conducts one phase of three phase currents from a power supply to the transformer subsystem. The series impedance path provides low impedance to the 1st harmonic and substantially higher, inductive impedance to higher harmonics of the power supply frequency.

Abstract: An LDO regulator (10) produces an output voltage (Vout) by applying the output voltage to a feedback input (6) of a differential input stage (10A) and applying an output (3) of the differential input stage to a gate of a first follower transistor (MP4) having a source coupled to an input (8) of a class AB output stage (10C) which generates the output voltage. Demanded load current is supplied by the output voltage during a dip in its value to a gate of a second follower transistor (MP5) having a gate coupled to the output of the input stage to decrease current in a current mirror (MN5,6) having an output coupled to a current source (I1) and a gate of an amplifying transistor (MN7). This causes the current source to rapidly turn on the amplifying transistor to cause it to rapidly turn on a cascode transistor (MN3), causing it to turn on a pass transistor (MP3) of the output stage.

Abstract: A quick response mechanism for a switching power system includes a detector and an adjustor connected to the detector. The detector is configured to directly monitor the drop of the output voltage of the switching power system so that a quick response could be immediately triggered when a load transient occurs. The adjustor is configured to adjust the duration of the quick response, thereby preventing the output voltage from undershoot or ringback.

Abstract: The present invention concerns an electrical installation or device equipped with a power supply unit comprising a voltage converter having primary and secondary parts respectively defining a primary side and a secondary side of this electrical installation or device. This power supply unit comprises a power management unit arranged on said primary side, the primary part of the converter being associated with a control circuit also arranged on said primary side and controlling the electrical energy flowing in the primary power path of said primary part. The control circuit receives from the power management unit at least a first control signal for switching OFF the electrical energy in said primary power path, said power supply unit entering a very low power mode (“Power-down” mode) when said first control signal is set to OFF so that the converter is not supplied anymore.

Abstract: A power converter and method of controlling a power switch therein to improve power conversion efficiency at low output current. In one embodiment, the power converter includes a first power switch coupled to a source of electrical power and a second power switch coupled to the first power switch and to an output terminal of the power converter. The power converter also includes a controller configured to alternately enable conduction of the first and the second power switches with a duty cycle in response to an output characteristic of the power converter. The controller is configured to control a level of current in the first power switch when the second power switch is substantially disabled to conduct.

Abstract: A system includes a current sensor to receive an input signal based on a sense current provided to load circuitry. The current sensor is configurable to generate an output signal from the input signal based, at least in part, on one or more configurable characteristics of the current sensor. The system also includes a processing element to compare the output signal from the current sensor to one or more programmable parameters. The processing element is configurable to direct a current controller to regulate the sense current provided to the load circuitry according to the comparison, and is further configurable to set a configurable parameter associated with the current sense amplifier.

Abstract: A DC-DC converter includes a switching stage and a control circuit coupled to provide an accurate current limit for peak current mode for the DC-DC converter. The control circuit is operative to provide a peak value of the peak current mode.

Abstract: A DC-DC converter includes an error amplifying circuit to output an error signal by amplifying differences between a reference voltage and a feedback voltage for an output voltage generated by switching an output transistor between on and off, a triangular wave generation circuit to generate a triangular wave, a PWM comparison circuit to compares the triangular wave with the error signal and output a duty control signal having a duty ratio based on the comparison, a pulse width control circuit to control a pulse width of the duty control signal output from the PWM comparison circuit, and a drive circuit to drive the output transistor according to a signal output from the pulse width control circuit.

Abstract: A controller for reducing the harmonics contents in the AC-to-DC converter that is capable of minimizing THD due to crossover distortion. The controller can approximate the shape of the current running through boost inductor to the sinusoidal waveform of the rectified line input voltage and in the meantime to keep the valley of rectified sinusoidal waveform line voltage close to local ground value. The controller can be used in a transition mode power factor correction device suitable for a wide range of AC line input voltage and output loading application.

Abstract: The present invention relates voltage conversion device in which a regulated output voltage is supplied by current pulses generated by the voltage conversion device from a voltage source. In particular, the invention relates to an improved control of an pulse frequency modulation (PFM) operation mode in which the frequency of the generated current pulses is modulated to regulated the desired output voltage, namely how PFM pulses can be generated without the need for a high-frequency clock of a time controlled system. By having pulse phases are current mode controlled and providing a mode detector to generate the right kind of current pulse, the high-frequency clock is no longer needed. Further, the presented solution allows for a higher PWM as well as PFM frequency, the external components of the converter can be made smaller. Eliminating the need for a high-frequency clock makes the device simpler, smaller and more energy-efficient.

Abstract: Disclosed are a switch controller, a switch control method, and a converter based thereon. The switch controller generates an input sensing voltage corresponding to the input voltage of the converter, and compares the input sensing voltage with a predetermined first reference value. The switch controller generates a zero cross detection signal with a first level or a second level depending upon the comparison result, and generates a reference clock signal varying in frequency in accordance with one cycle of the zero cross detection signal. The switch controller generates digital signals by using the reference clock signal and the zero cross detection signal. The digital signals synchronize with the zero cross detection signal, and increase in accordance with the reference clock signal during a half of one cycle of the zero cross detection signal, while decreasing in accordance with the reference clock signal during the other half cycle of the zero cross detection signal.

Abstract: A PFC counter which controls a switching element of voltage step-up chopper circuits arranged in parallel has a circuit (SLOG) generating a switch signal (GD_S) whose phase is shifted from that of a switch signal of one of the switching elements. This circuit has a first counter (COUNTM) which counts clock signals by a cycle unit of one of the switch signals; a second counter (COUNTS) which counts clock signals by a cycle unit having a predetermined phase difference with respect to one of the switch signals; and a first register (REG1) which holds a value counted by the first counter corresponding to a high-level period of one of the switch signals.

Abstract: A power supply that is capable of supplying power to an input/output channel for an Industrial Process Control System. The power supply includes a primary voltage converter having a first voltage input and a second voltage output, and overvoltage protection components that prevent the second voltage from rising above a predetermined maximum. The power supply includes a first low dropout regulator that is connected to receive the second voltage and to generate a third voltage, a second low dropout regulator that is connected to receive the second voltage and to generate a fourth voltage, and a third low dropout regulator that is connected to receive the fourth voltage and to generate a fifth voltage. The power supply provides an over-voltage fault tolerant self-testable architecture, allows for compact low cost individual channel isolation and fault tolerant EMI/RFI filtration.

Abstract: The present invention provides a reference voltage circuit making use of a non-volatile and non-modifiable storage of an electric charge. A tunable transformation module is adapted to transform a constant voltage corresponding to the constant stored charge into an output reference voltage. Further, a control loop provides tuning of the transformation module by means of an external calibration module with respect to a high precision reference voltage source. During a calibration procedure the transformation module is tuned in such a way that the output reference voltage equals the high precision reference voltage. After disconnecting reference voltage electronic circuit and calibration module, the output reference voltage is governed by the charge stored by means of the non-volatile storage and by the configuration of the tunable transformation module. It remains constant and accurate with respect to time and temperature and consumes only a minimum of electric current.

Abstract: Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply. The controller is coupled to limit a maximum on time period of the switch a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions.

Abstract: An average current mode switching converter is described for providing a regulated output current independent of load conditions, and a regulated output voltage as a function of the load connected to the converter. The converter includes an inductor, a modulator, a feedback loop, and a precharger. The modulator is configured to provide a regulated current through the inductor The feed back loop is coupled between the inductor and the modulator for regulating the current through the inductor. The precharger is configured and arranged so as to provide and maintain a preset minimum current through the inductor independent of the load so as to improve the recovery time of the converter from a step in the desired regulated output current. Also disclosed is a method of providing a regulated output current independent of load conditions at the output of an average current mode switching converter, and a regulated output voltage as a function of the load connected to the output of converter.

Abstract: A synchronous regulator includes a controller coupled to receive a reference signal and a feedback signal from the regulator and being operable to provide a pulse width modulation (PWM) signal at its output. The regulator includes at least one gate driver coupled to receive the PWM signal and includes a synchronous output switch having a phase node therebetween controlled by the gate driver, and also including regulator input current measurement circuitry. The regulator input current measurement circuitry includes a circuit that provides a signal representative of at least one phase node timing parameter. A sensing circuit is operable to sense inductor or output current provided by the regulator. A calculation circuit is coupled to receive the signal representative of the phase node timing parameters and the inductor or output current and is operable to determine the input current from the phase node timing parameters and the inductor or output current.

Abstract: A low drop out voltage regulator (LDO) is capable of operating in one of two different modes based on externally connected components. In one mode, the LDO directly generates a regulated output voltage. In a second mode, the LDO drives an external PNP transistor to generate a regulated output voltage. In both modes, a relatively large bypass capacitor may be connected to the output voltage node to bypass high-frequency loading on the output voltage node. However, the bypass capacitor creates a low frequency pole in the frequency response of the LDO, which can diminish phase margin and reduce overall stability. An on chip compensation network beneficially counteracts the low frequency pole with an appropriately placed zero, thereby resulting in improved phase margin and greater stability.

Abstract: An output monitoring comparator outputs an ON signal when an output voltage becomes lower than a reference voltage. A pulse modulator generates a pulse signal at a predetermined level, an ON time-period from when the ON signal is outputted. A driver circuit alternately turns ON, after a dead time, a switching transistor and a synchronous rectification transistor, based on the pulse signal. A light load mode detector compares a switching voltage at a connection point of the switching transistor and the synchronous rectification transistor, and ground potential, and at timing at which the ON signal is outputted from the output monitoring comparator, when the switching voltage is higher than the ground potential, nullifies the ON signal.

Abstract: An example controller for a switched mode power supply includes a zero-crossing detector, a feedback reference circuit, and a drive signal generator. The zero-crossing detector is coupled to generate a zero-crossing signal representative of a length of time that a zero-crossing condition of an input voltage of the power supply exists. The feedback reference circuit is to be coupled to receive a feedback signal and a reference signal, where the feedback signal is representative of an output of the power supply and where the controller is adapted to adjust the reference signal in response to the length of time that the zero-crossing condition exists. The drive signal generator is to be coupled to control switching of a switch included in the power supply in response to an output of the feedback reference circuit to regulate an output of the power supply.