Dean M Umberger

US Patent:

6925178, Aug 2, 2005

Filed:

Aug 22, 2003

Appl. No.:

10/646624

Inventors:

John C. Gammel - Birdsboro PA, US
David Chabinec - West Lawn PA, US
Dean Umberger - Stouchsburg PA, US

Assignee:

Legerity, Inc. - Austin TX

International Classification:

H04M009/08

US Classification:

37941301, 37939901, 379382

Abstract:

A subscriber-line interface circuit (SLIC) has tip and ring amplifiers connected to the tip and ring lines, respectively, of customer premises equipment (CPE). The SLIC returns the ringing signal (provided to the CPE from a power supply connected to the CPE's ring line), to ground or to battery, through the SLIC's tip amplifier. In one embodiment, the SLIC has three switches: S1 connecting the power supply to the ring line, S2 connecting the ring amp to the ring line, and S3 connecting the tip amp to the tip line. During ringing, S1 and S3 are closed to return the ringing signal to ground through the tip amp, which is preferably driven to saturation during ringing to reduce power consumption. By eliminating the fourth switch that appears in prior-art SLICs (e. g. , connecting the tip line to ground), SLICs of the present invention can be smaller and therefore less expensive to implement.

US Patent:

56317972, May 20, 1997

Filed:

Jul 24, 1995

Appl. No.:

8/506287

Inventors:

David P. Chabinec - Spring Township, Berks County PA
Dean M. Umberger - Stouchsburg PA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H02H 320

US Classification:

361 91

Abstract:

An overvoltage protection circuit using a diode bridge and a thyristor. The inputs to the bridge (first and second terminals) are coupled to a telephone line to be protected. The positive output of the bridge connects to a ground while the negative output of the bridge (intermediate node) connects through a thyristor to the ground. The thyristor is triggered into conduction when the voltage on the negative output of the bridge exceeds a reference voltage. The reference voltage is preferably the battery voltage for the telephone line.

US Patent:

63336642, Dec 25, 2001

Filed:

Aug 22, 2000

Appl. No.:

9/643253

Inventors:

Dean M. Umberger - Stouchsburg PA

Assignee:

Agere Systems Guardian Corp. - Allentown PA

International Classification:

H03K 1704

US Classification:

327376

Abstract:

An integrated ringing access switch circuit for telecommunications switching applications that provides improved dV/dt sensitivity at low operating power by using a pilot controlled rectifier, such as an SCR, that conducts at low ringing signal currents and operates to steer a bias current for causing a relatively larger controlled rectifier in parallel therewith to become conductive during higher load current operation. Also included is circuitry for preventing inadvertent turn-on of the SCRs in response to transient signals.

US Patent:

55324983, Jul 2, 1996

Filed:

Dec 6, 1994

Appl. No.:

8/350342

Inventors:

Dean M. Umberger - Stouchsburg PA
Craig B. Ziemer - New Holland PA

Assignee:

AT&T Corp. - Murray Hill NJ

International Classification:

G02B 2700

US Classification:

250551

Abstract:

A high sensitivity control circuit for a solid-state relay is disclosed for use in optically coupled solid state relay circuits having a light emitting diode. The control circuit reduces a loading effect of the turn-off circuit on a photodiode array allowing the photodiode array to operate the switching transistor to switch an input signal to a switching contact. A two stage CMOS transistor circuit acting as an amplifier is employed for high-speed switching. Deactivation of the light emitting diode reverse biases a sense photodiode to discharge the switching transistor to prevent switching of the input signal to the switching contact.

US Patent:

61694258, Jan 2, 2001

Filed:

Sep 29, 1998

Appl. No.:

9/162662

Inventors:

Dewayne Alan Spires - Plaistow NH
Dean Michael Umberger - Stouchsburg PA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01R 1900

US Classification:

327 56

Abstract:

The present invention is directed to an integrated circuit comprising a voltage source and a voltage sensing circuit having a switch circuit for sensing a switch voltage and a switch current; a voltage comparison circuit connected to the switch circuit for comparing the switch voltage to a limiting voltage; and a current limiting circuit connected to the switch circuit and the voltage comparison circuit, which is capable of limiting the switch current when the switch voltage reaches or exceeds the limiting voltage. In a preferred embodiment of the invention the switch circuit is a bi-directional switch circuit and the voltage comparison circuit incorporates a series of Zener diodes, wherein the current limiting circuit is a current foldback circuit.