Abstract: A driver circuit includes three non-contiguous high-voltage wells formed within a low-voltage monolithic silicon substrate; a high-side driver circuit fabricated within each of the wells; a separate logic input path for each of the high-side driver circuits, each input path comprising a logic signal input terminal, a signal amplifier, a noise filter, a pulse generator, and a high-voltage level shifter; an output terminal for each driver circuit, each output terminal coupled to its associated driver circuit output through a separate mask-configurable, variable-value output resistor bank, which reduces the number of external components needed for driver circuitry; a startup circuit which prevents operation of an associated high-side switch during periods of line voltage instability; and embedded capacitor banks, each of which is in close proximity to a high-side switch, for reducing capacitive, resistive and inductance losses associated with long metal lines.

Abstract: A driver circuit includes three non-contiguous high-voltage wells formed within a low-voltage monolithic silicon substrate; a high-side driver circuit fabricated within each of the wells; a separate logic input path for each of the high-side driver circuits, each input path comprising a logic signal input terminal, a signal amplifier, a noise filter, a pulse generator, and a high-voltage level shifter; an output terminal for each driver circuit, each output terminal coupled to its associated driver circuit output through a separate mask-configurable, variable-value output resistor bank, which reduces the number of external components needed for driver circuitry; a startup circuit which prevents operation of an associated high-side switch during periods of line voltage instability; and embedded capacitor banks, each of which is in close proximity to a high-side switch, for reducing capacitive, resistive and inductance losses associated with long metal lines.

Abstract: A filter monitoring device which detects variances in pressure of fluid flowing through a filter element in a filter assembly includes (1) an indicator for conveying data of changes in the differential pressure of the fluid in the filter assembly and (2) a temperature sensor for transmitting data showing any changes in temperature of the fluid being filtered. A microcontroller converts data received about changes in differential pressure and temperature sensing means to digital format and transmits the data along two differential digital lines to a driver and output connector.

Abstract: A method and circuit are provided for matching the brightness of a plurality of lamps driven by an AC drive current. The method may comprise the steps of: determining a brightness of each of said plurality of lamps, while said plurality of lamps are on, by using a current sensing device; selecting a first lamp having a lowest brightness from said plurality of lamps; and reducing a brightness of a second lamp to match said lowest brightness of the first lamp by interrupting the AC drive current in said scond lamp periodically for a predetermined number of half-cycles of said AC drive current. According to another implementation, a reference brightness maybe selected, or optionally a reference AC current level, and the method may reduce the drive current periodically so as to set the lamp brightness in relation to the reference brightness or optionally the reference AC current level.

Abstract: A discharge sustain driver circuit for a plasma display device, the driver circuit comprising a first transistor switching circuit for switching a DC bus voltage across the plasma display device; a storage capacitance; at least one inductor; and first and second bi-directional switching circuits coupled in series and being coupled to the first switching circuit to transfer charge from the plasma display device through the at least one inductor to the storage capacitance, and back to the plasma display device; and a controller for the bi-directional switching circuits to control the bi-directional switching circuits so as to receive the charge on the storage capacitance and return the charge in an opposite charge direction to the plasma display device.

Abstract: A filter monitoring device which detects variances in pressure of fluid flowing through a filter element in a filter assembly includes (1) an indicator for conveying data of changes in the differential pressure of the fluid in the filter assembly and (2) a temperature sensor for transmitting data showing any changes in temperature of the fluid being filtered. A microcontroller converts data received about changes in differential pressure and temperature sensing means to digital format and transmits the data along two differential digital lines to a driver and output connector.

Abstract: A circuit configuration which includes an input circuit referenced to one ground voltage and an output circuit referenced to another ground voltage capacitively coupled to the input circuit.

Abstract: A discharge sustain driver circuit for a plasma display device, the driver circuit comprising a first transistor switching circuit for switching a DC bus voltage across the plasma display device; a storage capacitance; at least one inductor; and first and second bi-directional switching circuits coupled in series and being coupled to the first switching circuit to transfer charge from the plasma display device through the at least one inductor to the storage capacitance, and back to the plasma display device; and a controller for the bi-directional switching circuits to control the bi-directional switching circuits so as to receive the charge on the storage capacitance and return the charge in an opposite charge direction to the plasma display device.

Abstract: A bi-directional switch comprising first and second semiconductor switching devices, a current sensor connected in series with the switching devices, thereby forming a series circuit, a driver circuit controlling the on/off operation of the first and second switching devices such that the first and second switching devices are substantially simultaneously turned on and off, the driver circuit turning the first and second switching devices on in response to a control input and turning the first and second switching devices off when current in the current sensor substantially drops to near a zero current. A discharge sustain driver circuit employing the bi-directional switches for a plasma display panel (PDP) is also described.

Abstract: A method for providing a soft start operation for a transistor driver circuit, comprising providing a saw tooth waveform from an oscillator at a given frequency; comparing the saw tooth waveform to a reference value; and modifying the saw tooth waveform as a result of the comparison to produce pulses of increased length when the reference value is below a value of the saw tooth waveform.

Abstract: A driver circuit for a transistor provides a soft start feature where pulses provided to the transistor are varied in duration during startup. The driver also provides an overcurrent protection feature for disabling a driver output for a safe period of time when an overcurrent condition is detected. The driver circuit includes an oscillator that produces a saw tooth wave and a narrow width pulse train for determining pulse width and dead time, respectively. The driver circuit may be used in half-bridge or full-bridge drivers.

Abstract: A method of matching the brightness of a plurality of lamps driven by an AC drive current may comprise the steps of: selecting a first one of said lamps having a lowest brightness; and reducing the AC drive current in a second lamp periodically so as to reduce the brightness of the second lamp to match that of the first lamp. According to another embodiment, a reference brightness may be selected, or optionally a reference AC current level, and the method may reduce the drive current periodically so as to set the lamp brightness in relation to the reference brightness or optionally the reference AC current level. A circuit for driving a lamp with controllable brightness may comprise: a drive circuit for supplying an AC drive current to the lamp; and a reducing circuit, advantageously comprised in an IC, for reducing the AC drive current in the lamp periodically to set the AC drive current in the lamp to match a reference.

Abstract: A power conversion circuit is provided. The circuit includes an isolated board mounted power module operable to convert a nominal input voltage into an intermediate bus voltage; the board mounted power module being unregulated and controlled in an open-loop; and a plurality of tightly regulated point-of-load converters operable to convert the intermediate bus voltage into respective point-of-load voltages to power a respective number of loads.

Abstract: A circuit configuration which includes an input circuit referenced to one ground voltage and an output circuit referenced to another ground voltage capacitively coupled to the input circuit.

Abstract: A bi-directional switch comprising first and second semiconductor switching devices, a current sensor connected in series with the switching devices, thereby forming a series circuit, a driver circuit controlling the on/off operation of the first and second switching devices such that the first and second switching devices are substantially simultaneously turned on and off, the driver circuit turning the first and second switching devices on in response to a control input and turning the first and second switching devices off when current in the current sensor substantially drops to near a zero current. A discharge sustain driver circuit employing the bi-directional switches for a plasma display panel (PDP) is also described.

Abstract: A driver circuit for a transistor provides a soft start feature where pulses provided to the transistor are varied in duration during startup. The driver also provides an overcurrent protection feature for disabling a driver output for a safe period of time when an overcurrent condition is detected. The driver circuit includes an oscillator that produces a saw tooth wave and a narrow width pulse train for determining pulse width and dead time, respectively. The driver circuit may be used in half-bridge or full-bridge drivers.

Abstract: A power conversion circuit is provided. The circuit includes an isolated board mounted power module operable to convert a nominal input voltage into an intermediate bus voltage; the board mounted power module being unregulated and controlled in an open-loop; and a plurality of tightly regulated point-of-load converters operable to convert the intermediate bus voltage into respective point-of-load voltages to power a respective number of loads.

Abstract: A non-isolated switched-capacitor converter. The output voltage is either fixed or adjustable. A control IC controls first and second semiconductor switches. The converter includes a first diode and a second diode connected in series, the diodes being connected in parallel with the output circuit; the first and second semiconductor switches connected in series; and a flying capacitance connected to the diode junction point. The load capacitance may be charged via the flying capacitance and the second diode in a charge cycle; and the load capacitance may be discharged via the first diode and the flying capacitance in a discharge cycle. The control IC has a high side well powered by the input supply voltage which drives the first semiconductor switch; a floating well powered by the flying capacitor which drives the second semiconductor switch; and a control circuit powered by an output voltage.

Abstract: A non-isolated, low cost, switched capacitor converter for providing auxiliary power for use in systems with a wide range of input voltages up to 600 Vdc. The converter delivers low output power with low EMI at efficiencies of around 70%. The output voltage is either fixed or adjustable. A control IC is provided for controlling first and second semiconductor switches in the switched-capacitor converter. The converter includes a load resistance and a load capacitance connected in parallel; a first diode and a second diode connected in series the diodes being connected in parallel with the output circuit; first and second semiconductor switches connected in series; the semiconductor switches being connected between the supply voltage input and the output circuit; and a flying capacitance connected across the second semiconductor switch and to the diode junction point.

Abstract: A self-oscillating circuit for driving high-side and low-side switching devices, such as MOSFETs connected in a half-bridge configuration. The circuit alternately turns on the switching devices by providing alternating gate pulses varying in duration or width. The pulses are separated by dead time to prevent cross conduction. At start up, the pulses increase from a minimum duration of zero to a maximum duration, while dead time duration simultaneously decreases to its minimum duration, to provide soft start.