Nathan E Wiscombe

US Patent:

52553140, Oct 19, 1993

Filed:

Mar 29, 1991

Appl. No.:

7/677546

Inventors:

Randy L. Applegate - Westminster CO
Ricky L. Overmyer - Golden CO
Stephen R. Peck - Boulder CO
John B. Sharp - Denver CO
Nathan E. Wiscombe - Broomfield CO

Assignee:

AT&T Bell Laboratories - Murray Hill NJ

International Classification:

H04M 342
H04M 164

US Classification:

379212

Abstract:

A switch-adjunct integration device uses multiple line appearances of one or more digital telephone lines to gather information on calls destined for an adjunct voice-mail system, to transfer the calls to analog phone lines leading to the voice-mail system, and to detect call completions. Call completion is detected by bridging some of the line appearances to the analog phone lines and monitoring the bridged line appearances for call status reported thereon by the switch. Call-related information, including call completion, is reported from the integration device to the voice mail system over a control link. The analog phone lines are connected to the voice mail system through switch relays on the integration device. The integration device momentarily opens a relay when it detects call completion on the connected analog line to further enhance call-completion signaling.

US Patent:

56684177, Sep 16, 1997

Filed:

Nov 14, 1995

Appl. No.:

8/557217

Inventors:

Nathan Wiscombe - Cedar Park TX
Ronald D. Shaw - Austin TX

Assignee:

Dell USA L.P. - Austin TX

International Classification:

H02J 700

US Classification:

307 64

Abstract:

A power loss detection system for a power supply including a main converter for providing regulated power, an activation circuit for mining on and off the main converter based on an active low activation signal, a standby power circuit for providing a standby power signal, and an internal pullup resistor coupled between the standby power and activation signals. The power supply asserts a power status signal indicative of the status of regulated power. Alternatively, an external detection circuit monitors the regulated power from the power supply and asserts a power loss signal indicative thereof. The control circuit asserts the activation signal low to turn on the main converter or floats the activation signal to turn off the main converter. If the power good or power loss signal indicates loss of regulated power, the control circuit floats the activation signal. If the activation signal goes or remains low after the activation signal is floated, then the power source has failed.

US Patent:

56729588, Sep 30, 1997

Filed:

Nov 14, 1995

Appl. No.:

8/555689

Inventors:

Alan E. Brown - Georgetown TX
Nathan Wiscombe - Cedar Park TX

Assignee:

Dell USA L.P. - Austin TX

International Classification:

G05F 140

US Classification:

323269

Abstract:

A feedback sensing system including a control circuit for detecting power failure of either power supply, and for controlling first and second switch circuits to modify the feedback sensing path of the other supply to the output load. In this manner, when one power supply fails, the feedback sensing path of the other power supply is rerouted to the output node to directly monitor and regulate the voltage across the load. Each switch circuit preferably operates to switch between two nodes along the respective output paths of the power supply, including a first node located before the current control device and a second node located between the current control device and the load. In one embodiment, each switch circuit includes two switches operated in a mutually-exclusive manner. In another embodiment, each switch circuit includes a relatively low value resistive device coupled between the output sense input and the first node, and a switch coupled between the output sense input and the second node for swamping the resistive device when activated or otherwise turned on.

US Patent:

56128541, Mar 18, 1997

Filed:

Jan 24, 1995

Appl. No.:

8/378126

Inventors:

Nathan Wiscombe - Cedar Park TX
Arthur Lopez - Austin TX
Victor Pecone - Austin TX

Assignee:

Dell USA, L.P. - Austin TX

International Classification:

H05K 502
H05K 714
G06F 116

US Classification:

361727

Abstract:

A computer is provided with a redundant power supply system using a plurality of power supply boxes having generally conventional, off-the-shelf configurations. The computer includes a housing having a wall opening spaced apart from and facing the side of a paralleling type circuit board having mounted thereon a plurality of AC electrical connectors and a spaced plurality of DC electrical connectors. The power supply boxes are mounted on carrier structures slidably received in the computer housing for drawer-like movement through the housing wall opening toward and away from the circuit boards. Each power supply box has an external wire bundle with blind mate DC electrical connectors mounted on the outer ends of its leads and supported by the carrier structure for mating connection with their associated circuit board connectors when the carrier structure is moved into adjacency with its associated circuit board. The carrier structure also supports an AC connector structure which is mated with its associated circuit board connector in response to such movement of the carrier structure. A switch carded by each carrier structure is operative to selectively enable and disable its associated power supply box and releasably lock the carrier structure to the computer housing.

US Patent:

46187790, Oct 21, 1986

Filed:

Jun 22, 1984

Appl. No.:

6/623646

Inventors:

Nathan Wiscombe - Broomfield CO

Assignee:

Storage Technology Partners - Louisville CO

International Classification:

H02J 110

US Classification:

307 60

Abstract:

A system and method of connecting power supplies in parallel that provides desired voltage regulation at the load and current sharing between the power supplies. The power supplies are connected in parallel at the load. Each power supply also has a sense line connected at the load. Each power supply includes means for measuring the current delivered to the load. Each supply also includes an electronically controlled variable resistive element in its respective sense line. The amount of current being supplied by each power supply to the load is measured. A controller determines if an unacceptable imbalanced current condition exists, i. e. , it determines which power supply is supplying too much or too little current and the controller selectively changes the value of the appropriate variable resistive element in the sense line of that power supply in order to change the current being delivered to the load in a direction that corrects for the imbalanced condition. All such corrections are controlled so that a desired voltage regulation is maintained at the load.

US Patent:

55923941, Jan 7, 1997

Filed:

Aug 31, 1995

Appl. No.:

8/522038

Inventors:

Nathan Wiscombe - Cedar Park TX

Assignee:

Dell U.S.A., L.P. - Austin TX

International Classification:

H02J 100

US Classification:

364492

Abstract:

A method and apparatus for balancing shared power supplies or regulating a power supply device includes disposing a transistor (310) in series with a power supply current that is supplied to a load resistor (316) The gate of the transistor (310) is controlled by a control circuit (320) to set the gate-to-source voltage thereon to define a desired current therethrough. The voltage across the transistor (310) is measured with a voltage detector (322) and then a current conversion device (324) is operable to use a look up table to determine from the gate voltage on the transistor (310) what the impedance across the drain-to-source is and then calculate the current. This current is then utilized by the control circuit (320) to control the current through transistor 310. This therefore allows transistor (310) to both provide the control operation and provide the sensing operation, thus eliminating the requirement for a separate sense resistor.