Carl B Nelson

US Patent:

RE39065, Apr 18, 2006

Filed:

Dec 10, 1996

Appl. No.:

08/794374

Inventors:

Carl T. Nelson - San Jose CA, US

Assignee:

Linear Technology Corporation - Milpitas CA

International Classification:

G05F 1/40

US Classification:

323284

Abstract:

An integrated circuit for use in implementing a switching voltage regulator, the integrated circuit including a power switching transistor, driver circuitry and control circuitry, which is operable in a normal feedback mode or an isolated flyback mode. The integrated circuit includes shutdown circuitry for placing the regulator in a micro-power sleep mode, and can be packaged in a five-pin conventional power transistor package. The terminals of the integrated circuit regulator perform multiple functions. A compensation terminal is used for frequency compensation, current limiting, soft-start operation and shutdown. A feedback terminal is used as a feedback input when the integrated circuit is in feedback mode, and as a logic pin to program the regulator for isolated flyback operation. The feedback terminal is also used to trim the flyback reference voltage.

US Patent:

48230707, Apr 18, 1989

Filed:

Aug 3, 1987

Appl. No.:

7/082989

Inventors:

Carl T. Nelson - San Jose CA

Assignee:

Linear Technology Corporation - Milpitas CA

International Classification:

G05F 1563

US Classification:

323285

Abstract:

An integrated circuit for use in implementing a switching voltage regulator, the integrated circuit including a power switching transistor, driver circuitry and control circuitry, which is operable in a normal feedback mode or an isolated flyback mode. The integrated circuit includes shutdown circuitry for placing the regulator in a micro-power sleep mode, and can be packaged in a five-pin conventional power transistor package. The terminals of the integrated circuit regulator perform multiple functions. A compensation terminal is used for frequency compensation, current limiting, soft-start operation and shutdown. A feedback terminal is used as a feedback input when the integrated circuit is in feedback mode, and as a logic pin to program the regulator for isolated flyback operation. The feedback terminal is also used to trim the flyback reference voltage.

US Patent:

56569653, Aug 12, 1997

Filed:

Jun 7, 1995

Appl. No.:

8/488042

Inventors:

Carl T. Nelson - San Jose CA
Robert Essaff - Fremont CA

Assignee:

Linear Technology Corporation - Milpitas CA

International Classification:

H03K 1700

US Classification:

327365

Abstract:

Circuits and methods are provide for improving the turn-off switching speed of a high-speed integrated circuit, bipolar switching regulator. The regulator runs at megahertz frequencies, yet is efficient as previously available bipolar integrated circuit switching regulators operating at much lower frequencies. The turn-off circuitry increases the speed at which the switch turns off by momentarily providing additional current to boost the base discharge current during the on-to-off transition period of the switch. In a preferred embodiment, the circuitry includes a capacitor for storing a charge, a resistor for limiting the amount of additional current provided, and a diode for delivering the additional current to the base of an NPN transistor, the collector of which is coupled to the switch's base, for boosting that transistors collector current and the switch's base discharge current. The diode then blocks current during the off-to-on transition period of the switch. Thus, the turn-off circuitry operates on an AC basis and only when the switch is turning off.

US Patent:

61114391, Aug 29, 2000

Filed:

Sep 15, 1998

Appl. No.:

9/153111

Inventors:

Carl T. Nelson - San Jose CA
Robert Essaff - Fremont CA

Assignee:

Linear Technology Corporation - Milpitas CA

International Classification:

H01J 1982

US Classification:

327110

Abstract:

A drive circuit for a high-speed integrated circuit, bipolar switching regulator is disclosed. The circuit runs at megahertz frequencies, yet is efficient as previously available bipolar integrated circuit switching regulators operating at much lower frequencies. The circuitry provides three switch drive currents: a first (nominal) current that is provided while the switch is off in order to conserve power; a second (boosted) current, provided while the switch is transitioning from off to on in order to increase the speed at which the switching element switches on; and a third (drive) current, provided after the switch has turned on for maintaining the switch at a desired point in saturation. The drive current, additionally, varies as a function of the load on the switch in order, again, to conserve power. Additional circuitry increases the speed at which the switch turns off, by momentarily boosting base discharge current during the on-to-off transition period of the switch.

US Patent:

59001267, May 4, 1999

Filed:

Jun 3, 1996

Appl. No.:

8/660195

Inventors:

Carl W. Nelson - Hayward CA
Richard D. Weir - Agoura Hills CA

Assignee:

Tulip Memory Systems, Inc.

International Classification:

C23C 1434

US Classification:

2041922

Abstract:

An improved magnetic-recording disk and a process for manufacturing magnetic-recording disks are disclosed. A precision cold-rolled authentic stainless steel is the substrate for a magnetic-recording disk. The surface of the substrate may be hardened by plasma nitriding, plasma carburizing, or plasma carbonitriding. A hard coating may be applied to the substrate by evaporative reactive ion plating or reactive sputtering of aluminum nitride, silicon nitride, silicon carbide, or nitrides, carbides, or borides of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, or tungsten.

US Patent:

54572983, Oct 10, 1995

Filed:

Jul 27, 1993

Appl. No.:

8/098417

Inventors:

Carl W. Nelson - Hayward CA
Richard D. Weir - Agoura Hills CA

Assignee:

Tulip Memory Systems, Inc. - Fremont CA

International Classification:

B23K 1000
H01L 21306

US Classification:

21912152

Abstract:

A hollow-cathode plasma device includes a hollow chamber composed of an electrically conductive material with a gas inlet at one end and a plasma outlet at an opposite end, a multipolar magnet array surrounding a portion of the chamber for isolating the plasma from the walls of the chamber, and a radiofrequency power source connected to the chamber.

US Patent:

40538320, Oct 11, 1977

Filed:

May 24, 1976

Appl. No.:

5/689235

Inventors:

Carl T. Nelson - Sunnyvale CA

Assignee:

National Semiconductor Corporation - Santa Clara CA

International Classification:

G01R 2106

US Classification:

324142

Abstract:

A pair of PNP and a pair of NPN transistors are connected in a balanced self clamping circuit in which the output response is proportional to the product of transistor emitter current and differential base voltage. The circuit is linear and accurate for use in reading true (in-phase) power in an a-c circuit.

US Patent:

48519537, Jul 25, 1989

Filed:

Oct 28, 1987

Appl. No.:

7/114219

Inventors:

Dennis P. O'Neill - Mountain View CA
Carl T. Nelson - San Jose CA

Assignee:

Linear Technology Corporation - Milpitas CA

International Classification:

H02H 300

US Classification:

361101

Abstract:

A current limit circuit is provided which may be used to limit the current conducted by a pass transistor in a low dropout voltage regulator circuit having no ground terminal. The output current of the regulator is sensed by a low value resistor in the collector of the transistor. The voltage developed across the resistor is proportional to the output current of the regulator, and is used to vary a current ratio which sets the current limit value. The gain of the current limit loop is increased by providing positive feedback during current limiting. A foldback network is provided which reduces the current limit value at higher input/output voltage differentials. The feedback provided by the foldback network has a breakpoint which is sensitive to the operating temperature of the regulator circuit.