Motorola Corporation

Brian D Meyer

Ira E Baskett

David M Heminger

Joseph H Slaughter, Iii

A piezoresistive pressure sensor (30) has four resistive diffused regions (32) coupled into a bridge configuration (33) with four junctions (36) and four inside corners (40). Each of the diffused regions has a first end connected to one of the four junctions and a second end connected to a different one of the four junctions. There are four contact diffusion terminals (34) disposed in contact with the bridge configuration, and each of the diffusion terminals is disposed at one of the four junctions such that the diffused regions are electrically connected essentially only by the contact diffusion terminals and an overlap (44, 46) is provided between each of the diffusion terminals and the inside corners to accommodate mask misalignment during manufacture. Thus, no tap is required to electrically connect the contact diffusion terminals to the resistive diffused regions of the bridge, which results in increased sensor sensitivity.

Piezoresistive sensor bridge having overlapping diffused regions to

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.

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Scottsdale, AZ, United States of America

Brian D Meyer