David C Kung

US Patent:

6869191, Mar 22, 2005

Filed:

Apr 28, 2003

Appl. No.:

10/424359

Inventors:

William G. Connelly - Vista CA, US
David L. Kung - Los Angeles CA, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G03B021/26
G03B021/14
G03B021/22
G03B021/32

US Classification:

353 94, 353119, 353 48, 352133

Abstract:

An apparatus for selectively positioning a first projector and a second projector to project an image through a single projection aperture. The apparatus comprises a first rail system, extending longitudinally along a second axis substantially perpendicular to the first axis; a first platform, translationally slidable in the second axis on at least a portion of the first rail system; a second rail system, disposed on the first platform; a second platform, adapted for mounting the first projector and translationally slidable along the first axis on the second rail system; and a third platform, adapted for mounting the second projector and translationally slidable in the second axis on at least a portion of the first rail system.

US Patent:

7893754, Feb 22, 2011

Filed:

Oct 2, 2009

Appl. No.:

12/587204

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

G05F 1/10

US Classification:

327538, 327513

Abstract:

A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R and R, and third and second temperature coefficients, TC and TC, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC, is substantially equal to TC×(R/(R+R))+TC×(R/(R+R)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

US Patent:

7999606, Aug 16, 2011

Filed:

Jan 31, 2011

Appl. No.:

12/931377

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Intergrations, Inc. - San Jose CA

International Classification:

G05F 1/10

US Classification:

327538, 327513

Abstract:

A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R and R, and third and second temperature coefficients, TC and TC, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC, is substantially equal to TC×(R/(R+R))+TC×(R/(R+R)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

US Patent:

8063622, Nov 22, 2011

Filed:

Oct 2, 2009

Appl. No.:

12/572952

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

G05F 1/00
G05F 1/10

US Classification:

323288, 327540

Abstract:

A circuit to control the slew rate of charging a capacitance using the capacitance is disclosed. An example circuit includes a regulator circuit to regulate a supply voltage during a normal operation mode of the circuit. A capacitance circuit is coupled to the regulator circuit. The regulator circuit is coupled to charge a capacitance between a first node and a second node of the capacitance circuit with a charge current. A slew rate control circuit is coupled to the regulator circuit and the capacitance circuit. The slew rate control circuit sets a slew rate of a voltage between the first and second nodes during a power up mode of the circuit.

US Patent:

8125265, Feb 28, 2012

Filed:

Aug 15, 2011

Appl. No.:

13/136921

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

G05F 1/10

US Classification:

327538, 327513

Abstract:

A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R and R, and third and second temperature coefficients, TC and TC, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC, is substantially equal to TC×(R/(R+R))+TC×(R/(R+R)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

US Patent:

8139384, Mar 20, 2012

Filed:

Jun 2, 2009

Appl. No.:

12/477058

Inventors:

David Kung - Hillsborough CA, US
William M. Polivka - Campbell CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

H02M 7/44

US Classification:

363 97, 363 2113

Abstract:

An example controller includes a constant current control circuit and an integrator included in the constant current control circuit. The constant current control circuit is to be coupled to receive an input current sense signal, an input voltage sense signal, and an output voltage sense signal. The control circuit is adapted to regulate an output current of a power supply by generating a control signal to control switching of a switch. The integrator is coupled to integrate the input current sense signal during a switching period of the control signal to generate an integrated signal representative of a charge taken from an input voltage source of the power supply. The constant current control circuit is adapted to control the switching of the switch such that the integrated signal is proportional to a ratio of the output voltage sense signal to the input voltage sense signal.

US Patent:

8278994, Oct 2, 2012

Filed:

Feb 16, 2012

Appl. No.:

13/398116

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

G05F 1/10

US Classification:

327538, 327513

Abstract:

A temperature independent reference circuit includes first and second bipolar transistors with commonly coupled bases. First and second resistors are coupled in series between the emitter of the second bipolar transistor and ground. The first and second resistors have first and second resistance values, R and R, and third and second temperature coefficients, TC and TC, respectively. The resistance values being such that a temperature coefficient of a difference between the base-emitter voltages of the first and second bipolar transistors, TC, is substantially equal to TC×(R/(R+R))+TC×(R/(R+R)), resulting in a reference current flowing through each of the first and second bipolar transistors that is substantially constant over temperature. A third resistor coupled between a node and the collector of the second bipolar transistor has a value such that a reference voltage generated at the node is substantially constant over temperature.

US Patent:

8299772, Oct 30, 2012

Filed:

Oct 13, 2011

Appl. No.:

13/272950

Inventors:

David Kung - Hillsborough CA, US
Leif Lund - San Jose CA, US

Assignee:

Power Integrations, Inc. - San Jose CA

International Classification:

G05F 1/10
G05F 1/00

US Classification:

323288, 327540

Abstract:

An example circuit includes a regulator circuit coupled to first and second nodes. A capacitance circuit and a slew rate control circuit are coupled between the first and second nodes. The regulator circuit is coupled to charge a capacitance of the capacitance circuit with a charge current. The slew rate control circuit is coupled to control a change in voltage over change in time between the first and second nodes during a power up mode of the circuit. The slew rate control circuit further includes a switch and a resistor. The slew rate control circuit is coupled to switch the switch in response to a voltage between the first and second nodes. A voltage drop across the resistor is limited to a base-emitter voltage drop of a transistor coupled between the first and second nodes to set the change in voltage over change in time.