James R Washburn

US Patent:

7817389, Oct 19, 2010

Filed:

Feb 18, 2009

Appl. No.:

12/379294

Inventors:

Alfredo Ochoa - Cave Creek AZ, US
George Templeton - Tempe AZ, US
James Washburn - Scottsdale AZ, US

International Classification:

H02H 3/20
H02H 9/04

US Classification:

361 56, 361111, 361 911

Abstract:

A semiconductor device for coupling a transient voltage at an input node to a reference node, the device having a bipolar transistor adapted to couple its collector to an input node and its emitter to the reference node and a driver device adapted to be coupled between the input node and the base terminal of the transistor such that the driver device is responsive to a transient voltage at the input node to turn on the transistor, thereby shunting the transient voltage to the reference node. Preferably, the input node is coupled to a high speed data transmission line that operates below 5 v and the reference node is coupled to ground and the transistor is an NPN transistor. The driver may preferably be a gate-drain connected MOS transistor with its gate-drain terminal coupled to the collector terminal of the transistor and its source terminal coupled to the base terminal of the transistor. Alternatively, the driver may be a light emitting diode (LED) or any other diode with a different material (band-gap) and die size than the LED, connected to the bipolar transistor to create a low voltage clamping device.

US Patent:

7968907, Jun 28, 2011

Filed:

Dec 9, 2008

Appl. No.:

12/314375

Inventors:

George Templeton - Tempe AZ, US
James Washburn - Scottsdale AZ, US

Assignee:

Pan Jit Americas, Inc. - Tempe AZ

International Classification:

H01L 21/70

US Classification:

257173, 257112, 257119, 257130, 257157, 257E21515, 257E23187

Abstract:

An over-voltage protection thyristor has reduced junction capacitance making it suitable for use in high bandwidth applications. The reduced capacitance is achieved through the introduction of a deep base region. The deep base region has a graded doping concentration which reduces with depth into the substrate. The thyristor is useful for protecting sensitive electrical equipment from transient surges.

US Patent:

20020125507, Sep 12, 2002

Filed:

Mar 5, 2002

Appl. No.:

10/090535

Inventors:

James Washburn - Scottsdale AZ, US
George Templeton - Tempe AZ, US

International Classification:

H01L029/76

US Classification:

257/213000

Abstract:

Interruptible high-voltage current limiter in a monolithic configuration: The structure comprises serially-connected complementary depletion-mode FET's where at least the gate of one of the FET's shares a common semiconductor region with the drain of the other FET. In a preferred embodiment, the FET's comprise a vertical n-channel depletion mode FET and a lateral depletion mode P-type FET. A Zener diode may be used to help control the cutoff voltage of the limiter.

US Patent:

20060082938, Apr 20, 2006

Filed:

Mar 9, 2005

Appl. No.:

11/075416

Inventors:

Alfredo Ochoa - Cave Creek AZ, US
George Templeton - Tempe AZ, US
James Washburn - Scottsdale AZ, US

International Classification:

H02H 9/00

US Classification:

361056000

Abstract:

A semiconductor device for coupling a transient voltage at an input node to a reference node, the device having a bipolar transistor adapted to couple its collector to an input node and its emitter to the reference node and a driver device adapted to be coupled between the input node and the base terminal of the transistor such that the driver device is responsive to a transient voltage at the input node to turn on the transistor, thereby shunting the transient voltage to the reference node. Preferably, the input node is coupled to a high speed data transmission line that operates below 5v and the reference node is coupled to ground and the transistor is an NPN transistor. The driver may preferably be a gate-drain connected MOS transistor with its gate-drain terminal coupled to the collector terminal of the transistor and its source terminal coupled to the base terminal of the transistor. Alternatively, the driver may be a light emitting diode (LED) or any other diode with a different material (band-gap) and die size than the LED, connected to the bipolar transistor to create a low voltage clamping device.

US Patent:

20060124959, Jun 15, 2006

Filed:

Nov 15, 2005

Appl. No.:

11/273609

Inventors:

George Templeton - Tempe AZ, US
James Washburn - Arlington VA, US

International Classification:

H01L 29/74

US Classification:

257157000

Abstract:

An over-voltage protection thyristor has reduced junction capacitance making it suitable for use in high bandwidth applications. The reduced capacitance is achieved through the introduction of a deep base region. The deep base region has a graded doping concentration which reduces with depth into the substrate. The thyristor is useful for protecting sensitive electrical equipment from transient surges.

US Patent:

43183158, Mar 9, 1982

Filed:

Sep 8, 1980

Appl. No.:

6/185195

Inventors:

James R. Washburn - Scottsdale AZ

International Classification:

B25B 1300

US Classification:

81 582

Abstract:

A split socket ratchet wrench is provided. The wrench has an elongate handle terminating at jaws at the head end of the wrench. The jaws receive a rotatable split socket and ratchet wheel rotatable therein. A manually actuable pawl has extending projections engageable with the ratchet teeth. A separate cable spool at the handle end of the wrench is fitted with a torsion spring. A cable or filament extends between the cable spool and the ratchet wheel. As the socket is rotated, it carries with it the cable which is spooled around a hub of the socket. When the wrench is disengaged from the nut, the pawl can be released and the cable spool will rewind returning the socket to the normal "open" position at which point a registry stop on the socket prevents the socket from rewinding past the open position. A separate locking device senses when the cable spool is completely payed out and prevents the mechanic from further turning the socket.

US Patent:

45299994, Jul 16, 1985

Filed:

Jul 9, 1982

Appl. No.:

6/396554

Inventors:

John R. Bender - Mesa AZ
James R. Washburn - Scottsdale AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01L 2974
H01L 2906
H01L 2348

US Classification:

357 38

Abstract:

An improved semiconductor device, particularly a gate controlled switch is provided by optimally fitting an involute spiral cathode-gate structure into a substantially square device. 4N cathode-gate branches radiate from a central gate portion and intersect the perimeter of the square device region at predetermined locations, N per side, where N is an integer. Four of the branches tangentially intercept the square perimeter at a distance R from a centerline where R is the radius of the central gate portion. The origin of the branches is angularly displaced from the line connecting the die center to the tangential intercept point by (L/R)- arctan (L/R) radians where L is half the edge length of the square device region. Improved thermal performance is obtained by thermally coupling the cathode heat spreader to the gate as well as cathode portions of the device.

US Patent:

52818322, Jan 25, 1994

Filed:

Jun 22, 1992

Appl. No.:

7/902251

Inventors:

Lowell E. Clark - Phoenix AZ
James R. Washburn - Scottsdale AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01L 2974

US Classification:

257109

Abstract:

A bidirectional two-terminal ungated thyristor (9) having two wide-base portions (25, 27). The bidirectional two-terminal ungated thyristor (9) has a first semiconductor device having a first narrow-base portion (28) in series with a first wide-base portion (25), and a second semiconductor device having a second narrow-base portion (26) in series with a second wide-base portion (27). A width of the first wide base portion (25) and a width of the second wide base portion (27) are decreased to decrease a total base width. The first and second wide-base portions (25, 27) having a decreased width produce a low forward voltage drop across the bidirectional two-terminal ungated thyristor (9); thus, improving a power dissipation capability of the bidirectional two-terminal ungated thyristor (9).