The number of cycles R of a fundamental frequency <SET>F (Hz) for a set value Tw (ms) of a set weld time [WELD] is first found as a real number. The number of cycles R conforms to the number of times (real number) of repetition of the fundamental frequency <SET>F cycle in the interval of the set weld time Tw and is given as Tw.times.<SET>F (step B.sub.1). An AC waveform cycle set value Ns (integer) for the set weld time Tw is then determined as an integer Min [N] that is equal ...

A power converter includes first and second voltage busses and a neutral bus. A first switching circuit, e.g., a rectifier circuit, is operative to selectively couple an input node thereof to the first and second voltage busses. A balancer circuit is operative to selectively couple the neutral bus to the first and second voltage busses such that relative magnitudes of respective first and second voltages on the first and second voltage busses are controlled responsive to respective first and sec...

A charger for a battery includes a power source and a control circuit. The battery has an internal resistance, at least one cell having a recommended charge voltage, and an aggregate recommended charge voltage. The power source is capable of providing an applied voltage and charge current to the battery. The control circuit is connected to the power source and is capable of detecting the applied voltage of the battery and enabling the charge current and applied voltage to the battery until the a...

Voltage regulator (10) provides current sense comparator (18) to detect the normal and standby modes of operation for voltage regulator (10). During a normal mode of operation, current sense comparator (18) de-asserts signal (MODE), causing voltage regulator (10) to regulate the output voltage to a predetermined level. Once the current (I.sub.in) has diminished below a predetermined value, current sense comparator (18) asserts signal (MODE) to indicate a standby mode. During the standby mode, re...

A method for mitigating current distortion on inverter supply lines that supply a load with power from a PWM inverter, the inverter including a switch and diode bridge constructed using devices that are characterized by losses that cause current distortion, the invert, lines and load together characterized by inductive and capacitive dynamics that also cause line current distortions, the method including identifying both a device drop error due to device operating characteristics and a system re...

Circuit and method for reducing voltage level variation in a bias voltage generated in a power converter device are provided. The method allows providing a first voltage source configured to supply a first voltage during one respective mode of operation of the power converter, wherein the level of the voltage supplied by the first voltage source is directly proportional to variation in an input voltage of the converter device. The method further allows providing a second voltage source configure...

This invention provides a power-on reset circuit capable of eliminating a wasteful current consumption after the power-on reset pulse generation even when the electric current flowing path means in the capacitor charge time constant circuit is configured by using a minute MOS element in which the off-leakage current tends to increase. More specifically, the present invention provides a power-on reset circuit comprising a power supply voltage sensing circuit 10, a capacitance element charge time ...

A regulating device for receiving a variable voltage and delivering a constant voltage includes a regulating element that includes a circuit for comparing the variable voltage with a reference voltage, a circuit for dividing the variable voltage by a factor, and a switching circuit for supplying the regulating element with a voltage equal either to the variable voltage or to the divided variable voltage. The switching circuit may be controlled by the comparison circuit in such a way that the reg...

An A.C./D.C. converter including a filtering capacitor and further including a first branch essentially including a first rectifying circuit and a current limiting circuit; a second branch essentially including a second rectifying circuit, the series voltage drop of which is limited to that of the switches forming it; and a selection circuit for selecting one of the two rectifying circuits.

In the present invention, an amplitude of a triangular wave from a triangular wave generating circuit is controlled depending on a power source voltage and further the current value for charging and discharging a capacitor is also controlled depending on the amplitude in such a manner that when the power source voltage drops the frequency of the triangular wave to be outputted is maintained at a predetermined frequency by reducing the current value and the amplitude and the waveform gradient is ...