Imtiaz Muhammed Khan

US Patent:

7023196, Apr 4, 2006

Filed:

Dec 12, 2003

Appl. No.:

10/734927

Inventors:

Imtiaz Khan - Trabuco Canyon CA, US
Malcolm Critchley - Scottsdale AZ, US

Assignee:

Leach International Corporation - Buena Park CA

International Classification:

G01R 31/02
H02H 9/08

US Classification:

324158, 324521, 324536, 361 20, 361 50

Abstract:

Apparatus and methods for detecting high level arc faults in aircraft power systems are disclosed. One embodiment of the invention with reduced susceptibility to nuisance trips includes three low pass filters each having an output connected to a threshold detector. In addition, a three input comparator is connected to an output of each of the threshold detectors and a fault verification circuit is connected to an output of the three input comparator. An embodiment of the method of the invention for detecting arc faults in three phase aircraft power systems involves detecting at least one of the three phases having a current exceeding a predetermined threshold, detecting differences between the three phases and generating a signal indicative of difference being detected between the three phases for a time period exceeding a predetermined duration.

US Patent:

7738230, Jun 15, 2010

Filed:

Jan 4, 2008

Appl. No.:

11/969861

Inventors:

Robert C. Mallon - Buena Park CA, US
Imtiaz Khan - Trabuco Canyon CA, US

Assignee:

Leach International Corporation - Buena Park CA

International Classification:

H02H 3/00

US Classification:

361114, 361 42

Abstract:

A non-volatile status indicator switch is provided. In one embodiment, the invention relates to an aircraft electrical system including a fault detection circuit coupled to a relay, and a fault indicator circuit coupled to the fault detection circuit and to a control input of the relay, wherein the fault indicator circuit includes a nonvolatile memory element, wherein the fault detection circuit is configured to detect a fault and to provide a signal indicative of the fault to the fault indicator circuit, and wherein the fault indicator circuit is configured to respond to the signal indicative of the fault by providing a predetermined control signal to the relay and by storing information indicative of the detection of the fault in the nonvolatile memory element.

US Patent:

7747879, Jun 29, 2010

Filed:

Feb 16, 2006

Appl. No.:

11/356487

Inventors:

Farshid Tofigh - Mission Viejo CA, US
Otmar Kruppa - Deiningen, DE
Imtiaz Khan - Trabuco Canyon CA, US
Iraj Ghahramani - Mission Viejo CA, US
David Lawton - Santa Ana CA, US
Kent Policky - Tustin Ranch CA, US

Assignee:

Leach International Corporation - Buena Park CA

International Classification:

G06F 1/00
H02H 3/00
H02H 7/00

US Classification:

713300, 396116, 361 5, 361 7, 361 42, 361 44

Abstract:

Solid state power controllers are described that include a switch controlled by a microcontroller and communication contacts. In one aspect of the invention, the microcontroller is galvanically isolated from the communication contacts using magnetoresistive isolation. In another aspect of the invention a number of solid state power controllers are connected to an external microcontroller to form a power distribution array. In addition, messages exchanged between the external microcontroller and the solid state power controllers can be used to configure the solid state power controllers and provide a user interface.

US Patent:

8190934, May 29, 2012

Filed:

Feb 10, 2010

Appl. No.:

12/703628

Inventors:

Farshid Tofigh - Mission Viejo CA, US
Otmar Kruppa - Deiningen, DE
Imtiaz Khan - Trabuco Canyon CA, US
Iraj Ghahramani - Mission Viejo CA, US
David Lawton - Santa Ana CA, US
Kent Policky - Tustin Ranch CA, US

Assignee:

Leach International Corporation - Buena Park CA

International Classification:

G06F 1/00
H02H 7/00
H02H 9/02

US Classification:

713300, 361 2, 361 42, 361100, 361115

Abstract:

Solid state power controllers in various configurations are provided. One such solid state power controller includes a power connector, a load connector and at least one communication connector, a solid state switch electrically connectable between the power connector and the load connector, where the switch includes an input, a microcontroller coupled to the input of the solid state switch, and current sensing circuitry coupled to the microcontroller and configured to sense a current flowing through the solid state switch, the current sensing circuitry including an amplifier having an offset error, where the current sensing circuitry is configured to generate a signal indicative of the current flowing through the solid state switch, and bias the generated signal to a predetermined level to substantially eliminate the offset error in the amplifier.

US Patent:

8412966, Apr 2, 2013

Filed:

Apr 25, 2012

Appl. No.:

13/456183

Inventors:

Farshid Tofigh - Mission Viejo CA, US
Otmar Kruppa - Deiningen, DE
Imtiaz Khan - Trabuco Canyon CA, US
Iraj Ghahramani - Mission Viejo CA, US
David Lawton - Santa Ana CA, US
Kent Policky - Tustin Ranch CA, US

Assignee:

Leach International Corporation - Buena Park CA

International Classification:

G06F 1/00
H02H 3/00
H02H 7/00

US Classification:

713300, 398116, 361 5, 361 7, 361 42, 361 44

Abstract:

Solid state power controllers are described that include a switch controlled by a microcontroller and communication contacts. In one aspect of the invention, the microcontroller is galvanically isolated from the communication contacts using magnetoresistive isolation. In another aspect of the invention a number of solid state power controllers are connected to an external microcontroller to form a power distribution array. In addition, messages exchanged between the external microcontroller and the solid state power controllers can be used to configure the solid state power controllers and provide a user interface.

US Patent:

20170117698, Apr 27, 2017

Filed:

Oct 26, 2015

Appl. No.:

14/923372

Inventors:

- Buena Park CA, US
Imtiaz Khan - Trabuco Canyon CA, US

International Classification:

H02H 3/08

Abstract:

There is provided a protection circuit configured to indicate an overcurrent condition of a conductor conducting a load current, the protection circuit including a first current integrator and a second current integrator, each of the first and second integrators being configured to integrate an input voltage proportional to the load current, a summing amplifier configured to receive an offset voltage, to amplify a signal from the second integrator, and to generate a trip threshold based on the input voltage and the offset voltage, and a comparator configured to compare an output of the first current integrator and the trip threshold, and to generate a trip signal at a trip time when the trip threshold is equal to an output of the first integrator, the trip signal indicating an overcurrent condition.