Engineering topics

Hochmair, E. S.

Publications and source records attributed to Hochmair, E. S..

5 records

NASA NTRS1974

Integrated P-channel MOS gyrator

A gyrator circuit is described which is of the conventional configuration of two amplifiers in a circular loop, one producing zero phase shift and the other producing 180 phase reversal, in a circuit having medium Q composed of all field effect transistors of the same conductivity type. The current source to each gyrator amplifier comprises an amplifier which responds to changes in current, with the amplified signals feed back so as to limit current. The feedback amplifier has a large capacitor connected to bypass high frequency components, thereby stabilizing the output. The design makes possible fabrication of circuits with transistors of only one conductivity type, providing economies in manufacture and use.

Hochmair, E. S.↗

NASA NTRS1973

Integrated p-channel MOS gyrator

Several circuits can be integrated into one chip for applications which require more than one gyrator. They can also be integrated with other p-channel MOS circuits to eliminate need for external connections. Devices can operate at economical low-power levels, because they use FET amplifiers that do not degrade with decreases in supply.

Hochmair, E. S.↗

NASA NTRS1973

Integrable power gyrator

Further study of Y-matrix and Z-matrix configuration has led to development of efficient, dependable high-quality gyrators. Efficiency of new gyrators may approach theoretical limit of 78.5% with further improvements. Both designs are comparatively easy to integrate by implementing technology used with conventional operational amplifiers.

Hochmair, E. S.↗

NASA NTRS1973

Gyrator circuit using field effect transistors

Gyrator circuit is especially useful in integrated circuits for such purposes as simulating inductors with capacitors. Circuit is adaptable to semifloating and full floating configurations. It has excellent response, low power consumption, and high energy storage capacity.

Hochmair, E. S.↗

NASA NTRS1973

Gyrator employing field effect transistors

A gyrator circuit of the conventional configuration of two amplifiers in a circular loop, one producing zero phase shift and the other producing 180 deg phase reversal is examined. All active elements are MOS field effect transistors. Each amplifier comprises a differential amplifier configuration with current limiting transistor, followed by an output transistor in cascode configuration, and two load transistors of opposite conductivity type from the other transistors. A voltage divider control circuit comprises a series string of transistors with a central voltage input to provide control, with locations on the amplifiers receiving reference voltages by connection to appropriate points on the divider. The circuit produces excellent response and is well suited for fabrication by integrated circuits.

Hochmair, E. S.↗