Bbc Brown, Boveri & Company, Limited

International Telephone and Telegraph Corporation

International Standard Electric Corporation

Jozef Cornu

Jean R Taeymans

Erich Weisshaar

Santanu Das

Daniel C Upp

Roland Sittig

Ramon C Chea, Jr

Johan M Danneels

Jacques Talbot

A telephone line circuit and system for interfacing digital exchange line circuits to a terminal interface of a switching network is disclosed. The system includes controllable active circuit impedance matching means for reducing impedance mismatch between a selected line circuit and the terminal interface. Control means controls both the active circuit impedance matching means for adjusting the effective circuit impedance to a value within a predetermined range, and the conditioning circuit gain pads for selectably adjusting the gain of a transmitted signal. Additionally, control means controls the d.c. line impedance and voltage for adjusting the effective line feed current to the subscriber loop, and provides interfaces for a plurality of line circuits to both a switching network and external processor. Supervision means provides supervision control signals to the control means and thereby permits the telephone line circuit system to provide desired telephone system functions.

Telephone line circuit and system

The signal generator comprises a charge transfer device providing an output signal having any desired shape so that it is particularly useful in an A/D or D/A converter. In this device charges are transferred under electrodes of which some are split in order to obtain charge portions which are then removed or transferred to the output of the device where they are added to or subtracted from previous charge portions to finally obtain a desired output signal.

Signal generator and signal converter using same

A semiconductor power element comprising two successive opposed polarity planar pn junctions, said element being positively tapered on its lateral surface in the regions of both pn junctions to form an average angle of both tapers of between 30.degree. and 60.degree..

Semiconductor power component

A bistable semiconductor component for high frequencies with a semiconductor chip includes a sequence of at least four zones of alternating opposed types of conductivity. The outer zones form the emitter zones and are more heavily doped than the two inner zones. The base zones are so doped that with a voltage V.sub.R smaller than or at most equal to the maximum inverse voltage V.sub.RS applied in the reverse direction across the two emitter zones, the shortest distance W between the two blocking layers formed at the two outer junctions is less than the diffusion length L.sub.B of the charge carriers in the base zones.

Bistable semiconductor component for high frequencies having four zones

Growing community of inventors

Stekene, Belgium

Jozef Cornu