Lucent Technologies Inc.

Bell Telephone Laboratories

American Telephone & Telegraph Co., At&t Bell Laboratories

Roman Ostapiak

David S Kerr

Norman Gerard Ziesse

Rudolph Scuderi

Frank M Magalhaes

Ralph Walk

Robert Wilson Michelet

Patricia Lynn Gruber

A current limiting circuit for use in broadband and combined broadband and telecommunications networks is described. A current limiting element is triggered into a high impedance state in the event of excess current on the line. A sensing element detects the resulting decrease in voltage and operates a switch which disconnects the current limiting element. Timing circuitry reconnects the current limiting element a predetermined period of time after the current limiting element returns to its low impedance state.

Current limiting circuit

A DC to DC converter combines a half-bridge inverter with a resonant rectifier through a series LC circuit which conducts power at substantially a single frequency. Energy stored in the parasitic capacitors of the two power switches are transferred from one parasitic capacitor to the other in order to enhance efficiency of operation. The transfer is controlled by controlling the relative phase between the voltage and current in the inverter section.

Zero voltage switching half bridge resonant converter

A converter circuit includes an inrush current limit circuit to limit the initial transient surge of inrush current to a power supply upon the initial application of voltage to the power supply input. After the initial start-up transient inrush current surge, the inrush current limit circuit is switched out of the input signal path to reduce power dissipation during normal steady state operation of the circuit. If the input voltage magnitude decreases significantly at any time, the inrush current limit circuit is reset to limit any further current surges.

Inrush current limit circuit with reset response to lowered input voltage

Growing community of inventors

Pine Brook, NJ, United States of America

Roman Ostapiak