Abstract: A voltage-controlled oscillator device with an LC-resonant circuit, in particular for implementing integrated voltage-controlled oscillators for the lower GHz range, is disclosed. The device achieves continuous frequency tunability in a wide range in particular with a low level of phase noise and phase jitter. In the voltage-controlled oscillator, a second inductor can be periodically switched in parallel and/or in series with at least one first inductor of the LC-resonant circuit by way of a switching means actuated with the oscillator frequency. A control input of the switching means is connected to a variable dc voltage. In that respect the relationship of the duration of the conducting state and the duration of the non-conducting state of the switching means is variable within an oscillation period of the oscillator in dependence on the value of the control voltage.

Abstract: A bipolar transistor structure wherein the emitter zone is produced by outward diffusion from etching residues which are formed by deposition of conductive material and re-etching, with the etching residues forming part of the emitter terminal region. In addition to individual transistors, pairs of transistors having coupled emitters can also be produced and employed in hig precision differential amplifiers. Memory cells can also be produced which have low surface requirements, particularly due to the reproduceable attainment of emitter widths below one micron. Since the methods enable the production of completely self-aligned transistors, they can be implemented with straightforward steps which are largely independent of lithography. Emitter widths in the range of about 0.2 to 0.5 microns can be produced.