Joseph William Slaughter

US Patent:

57510253, May 12, 1998

Filed:

Jan 2, 1997

Appl. No.:

8/778432

Inventors:

David M. Heminger - Mesa AZ
Joseph H. Slaughter - Chandler AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01L 2941

US Classification:

257173

Abstract:

A current limiter (15) is formed between a silicon substrate (10) and a source region (17) by a channel implant region (20). The channel implant region (20) is not modulated by a gate structure so the maximum voltage that can flow between the silicon substrate (10) and the source region (17) is determined by the doping profile of the ever-present channel implant region (20). A pinch-off structure (12) is used to form a depletion region which can support a large voltage potential between the silicon substrate (10) and the source region (17). In an alternate embodiment, a bipolar device is formed such that a limited current flow can be directed into a base region (32) which is used to modulate a current flow between silicon substrate (30) and an emitter region (38). Using the current limiters (15,35) it is possible to form an AC current limiter (50) that will limit the current flow regardless of the polarity of the voltage placed across two terminals (51,52).

US Patent:

56295367, May 13, 1997

Filed:

Nov 21, 1995

Appl. No.:

8/560774

Inventors:

David M. Heminger - Mesa AZ
Joseph H. Slaughter - Chandler AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01L 2941

US Classification:

257173

Abstract:

A current limiter (15) is formed between a silicon substrate (10) and a source region (17) by a channel implant region (20). The channel implant region (20) is not modulated by a gate structure so the maximum voltage that can flow between the silicon substrate (10) and the source region (17) is determined by the doping profile of the ever-present channel implant region (20). A pinch-off structure (12) is used to form a depletion region which can support a large voltage potential between the silicon substrate (10) and the source region (17). In an alternate embodiment, a bipolar device is formed such that a limited current flow can be directed into a base region (32) which is used to modulate a current flow between silicon substrate (30) and an emitter region (38). Using the current limiters (15, 35) it is possible to form an AC current limiter (50) that will limit the current flow regardless of the polarity of the voltage placed across two terminals (51, 52).

US Patent:

53919971, Feb 21, 1995

Filed:

Oct 28, 1993

Appl. No.:

8/141366

Inventors:

Brian D. Meyer - Scottsdale AZ
David M. Heminger - Mesa AZ
Joseph H. Slaughter - Chandler AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G02B 2700
H03K 1914

US Classification:

327514

Abstract:

An optically isolated N-channel MOSFET driver turns on a MOSFET device in response to an optical input signal to drive a load. The turn-on time of the MOSFET is enhanced by a current boost circuit. As the MOSFET transcends to an on state and delivers current to the load, the voltage across the device diminishes and causes the current boost circuit to become inactive thus reducing to zero the current drain consumed by the current boost circuit. A photovoltaic array maintains the MOSFET operation. An optically isolated SCR is respondent to the absence of a light signal to turn off the MOSFET. Furthermore, the optical decoupling of the SCR, between the gate and source of the MOSFET device, is arranged to provide enhanced noise immunity. A voltage clamping circuit coupled between the gate and source of the MOSFET device provides additional protection to the device from large over voltages.

US Patent:

51287293, Jul 7, 1992

Filed:

Nov 13, 1990

Appl. No.:

7/611625

Inventors:

Paul G. Alonas - Scottsdale AZ
Joseph H. Slaughter - Mesa AZ
Niraj Kohli - Scottsdale AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01L 3112
H01L 4500
H01L 2348

US Classification:

357 19

Abstract:

Improved resistance to electrical instability of opto-isolators subjected to large stand-off voltages is obtained by coating the semiconductor light sensing element with a high resistivity layer of amorphous silicon while leaving most of the surface PN junction perimeter and nearby regions free of metal. The amorphous silicon prevents mobile ions in the encapsulation, which are driven to the detector surface by the stand-off voltage, from inverting or modulating the conductivity of the detector surface and causing instability. The amorphous silicon also makes it possible to leave most of the light sensitive PN junctions and nearby regions free of metal, thereby simplifying design of complex IC detector chips and increasing sensitivity.