Abstract: A semiconductor circuit device equipped with an intermediate voltage generating circuit having achieved circuitry simplification and a saving in power consumption is to be provided. In a semiconductor integrated circuit containing within its chip a voltage generating circuit for generating an external source voltage VDD or a voltage which is half of a voltage internally generated on the basis of that external voltage, the voltage generating circuit consisting of two sets of differential circuits for comparing a reference voltage and the output voltage of a push-pull output circuit and driving the output transistor of the push-pull output circuit, and the differential circuits being provided with offsets to prevent a penetrating current from flowing to the push-pull output circuit. The offsets are formed by differentiating the channel width/channel length ratios or the threshold voltages of differential pairs of MOSFETs.

Abstract: A four quadrant power conversion topology comprising a multi-winding inductor, four switches, and four diodes is disclosed. The four quadrant power conversion is utilized in a number of power conversion devices such as a power efficient non-linear power amplifier that comprises the 4Q power conversion topology of the present invention and a switch-control-signal generator coupled to the 4Q power conversion topology. The switch-control-signal generator generates switch activation signals for driving the four switches of the 4Q power conversion topology.

Abstract: A power supply or converter has an AC-voltage source to which a number of rectifiers are connected, with at least one of the rectifiers having a switching stage by which, in a feedback mode, energy can be fed back to the AC-voltage source from a DC-voltage terminal and/or from a capacitor of the rectifier. Such an arrangement achieves an energy symmetry among a number of connected users, e.g. back-feeding output stages, with low losses and low cost in terms of circuitry.

Abstract: A DC to DC converter particularly suited for use to boost or reduce the voltage with single battery systems allows insertion of the battery in either polarity through use of a symmetrical arrangement of solid-state switches which alternate charging an inductor for the DC to DC converter operation and establishing a ground depending on the polarity of the battery. The use of a solid-state switch to establish a ground avoids the severe voltage drop required of rectifier systems.

Abstract: A pulse frequency modulation drive circuit (1114) for a piezoelectric transformer (1102) is provided. Circuit (1114) includes a piezoelectric transformer (1102) having a resonant frequency and an input and an output section. A frequency feedback network connected to the piezoelectric transformer (1102) and an output level sense (1112) connected to the piezoelectric transformer (1102) is also provided. A drive circuit (1114) has a first switch (S.sub.1) and a third switch (S.sub.3) having a capacitance (1118) therebetween. A second switch (S.sub.2) and a fourth switch (S.sub.4) connect a supply voltage (V.sub.IN) to each of a pair of inductors (L.sub.1 and L.sub.2) and the second switch (S.sub.2) and the fourth switch (S.sub.4) are driven 180.degree. out of phase at the resonant frequency of the piezoelectric transformer (1102).

Abstract: A voltage regulator (10) that regulates an input voltage. The voltage regulator (10) includes a current source (20) that generates a reference current. The voltage regulator also includes a voltage translation circuit (30), coupled to and responsive to the current source (20), that increases the input voltage to generate a differential voltage signal. The voltage regulator (10) further includes a differential comparator circuit (40) coupled to the voltage translation circuit (30) that generates a control signal based on the differential voltage from the voltage translation circuit (30) to indicate when the input voltage should be adjusted.

Abstract: A nonlinear carrier controlled power factor correction circuit operates in the continuous and discontinuous conduction modes and provides unity power factor at the input of a power supply by only sensing the output voltage and the current flowing through a diode of a rectifier circuit. The power factor correction circuit monitors a level of current flowing through the diode and generates an integrated voltage signal representative of the level of current flowing through the diode. The integrated voltage signal is compared to a periodic, carrier waveform signal generated using a feedback signal corresponding to a level of an output voltage delivered to a load. A difference between the feedback signal and a reference signal determines the waveshape and characteristics of the carrier waveform. Preferably, leading edge modulation is used to control the duty cycle of a switch within the rectifier circuit.

Abstract: This invention provides a valveless method and apparatus for high speed switching of liquid flow between intersecting microchannels. Liquid flow is controlled by manipulating external driving pressures. The switch comprises three intersecting microchannels, each having a liquid reservoir at its nonintersecting end for liquid inlet and outlet. It further includes applying a driving pressure to each reservoir switching the driving pressures. The microswitch of this invention operates to establish a liquid flow from a first channel to a second channel by applying a pressure differential between the first and second reservoirs, while simultaneously preventing flow into the third channel by applying a pressure to the third reservoir which equals the pressure at the junction of the three channels. By switching one or more driving pressures, the flow to the second channel can be stopped and the liquid flow redirected to the third channel.

Abstract: A current sharing circuit forces current delivered to a common load to be provided in substantially equal shares by two or more D.C.-to-D.C. converters, particularly those of the type whose output varies according to a predetermined functional relationship with the frequency of a controllable signal generated by the converter indicating its operating frequency. The load current delivered by such converters typically varies approximately proportionately with the converter operating frequency when the converter input and output voltages are held constant. Based on the frequency of these indicating signals and the predetermined relationship between their frequency and the output current of each respective converter, it is determined which particular one of the converters is presently supplying the largest share of load current. The outputs of each of the other converters are adjusted to share the load more equally among all the converters.