Micronas Intermetall Gmbh

Itt Manufacturing Enterprises, Inc.

Deutsche Itt Industries Gmbh

Norbert Greitschus

Ulrich Theus

Knut Caesar

Hans-Gunter Zimmer

A DC/DC converter including a switching transistor, an inductor, a smoothing capacitor, and a switching element which are connected so as to convert an input voltage U.sub.E to an output voltage U.sub.A greater or less than the input voltage U.sub.E. The current through the inductor can be measured by providing a comparator having a first input connected to the switching transistor, and a second input connected to a reference transistor and a reference current source so as to fix the switching threshold of the comparator at the second input.

DC/DC converter

An integrated driver circuit for driving different capacitive loads, which includes a setting element. The setting element develops a setting signal S for a given numerical measure signal M. The numerical measure signal M is developed by an input device, which is coupled to the setting element. The numerical measure signal M corresponds to one of the different capacitive loads which is driven by the driver circuit. Coupled to the setting element is an output stage, which provides an output current that corresponds to the setting signal S.

Digital driver circuit for an integrated circuit

A semiconductor structure for creating resistor networks, particularly ladder networks, has resistive sections made of semiconductor material and metal contact areas. A continuous semiconducting resistor strip is provided as a primary arm. Along this continuous primary arm, metal contact areas which contact the resistor strip at the side are provided in accordance with the desired resistor ratio and in order to form corresponding series resistors. In a ladder network, shunt arms have one end connected directly to the long side of the primary arm via the semiconductor material. At the other end of each of the shunt arms, a respective metal contact area is provided.

Semiconductor structure ladder network configuration

The invention relates to a digitally adjustable crystal oscillator having a quartz crystal and a monolithic integrated oscillator circuit including a series combination of a first frequency-adjusting capacitor C1 and a second frequency-adjusting capacitor C2 connected in parallel with the quartz crystal and comprising parallel-connected first capacitance stages and parallel-connected second capacitance stages, respectively, and an inverter circuit connected in parallel with the quartz crystal and comprising a feedback resistor R.sub.K, the output of the innverter circuit being connected to a load resistor. The inverter circuit comprises parallel-connected inverter stages, and switching elements are provided within the inverter stages and cqapacitor stages in such a way that a respective one of the inverter stages as well as a first capacitance stage C.sub.1i and a second capacitance stage C.sub.2i are switchable into or out of circuit by means of a control signal I.sub.i.

Growing community of inventors

Freiburg, Germany

Norbert Greitschus