Abstract: A current limit circuit for protection of an intelligent power switch includes a series circuit of a sense transistor and a sense resistor coupled to the power semiconductor transistor switch so that the sense resistor current is a fraction of, and is proportional to, the power transistor current. A pull-down transistor is coupled to the control electrode of the power transistor switch. A feedback circuit including a series connection of a diode-connected transistor and a reference V source is coupled between the sense resistor and the control electrode of the pull down transistor. The feedback circuit produces a voltage level shift and the circuit provides an accurate limit on the power transistor current independent of any variations in threshold voltage.

Abstract: A magnetic resonance and apparatus in which an examination zone is exposed, preferably repeatedly, with a sequence in which the same RF pulse is both selective to fat, for acting in a fat suppression scheme within the sequence and is configured for inducing substantial magnetization transfer contrast. Design parameters are given for a 1-2-1 binomial RF pulse and a 1-2-1-1-2-1double binomial RF pulse having a 0.degree. net flip angle at the Larmor frequency of water protons and a nominal 180.degree. net flip angle at the Larmor frequency of fat bound protons. The partial derivatives of the latter nominal flip angle with respect to chemical shift and with respect to RF amplitude are each zero. Each of these RF pulse designs is implemented by a pulse which is substantially rectangular in amplitude, but which has alternations of phase between 0.degree. and 180.degree. during its duration to form the sub-pulses.

Abstract: A surface smooth enough to allow the formation thereon of a single domain magnetic element is obtained by covering a polished layer with a thin layer of the same material, to smooth sharp edges and corners. The resulting structure is useful in thin film magnetic heads.

Abstract: The present invention provides a track format for an optical record carrier that is useful in producing a tracking signal with a substantially constant slope at its zero-crossing point for a range of track pitches. The preferred embodiment of track format is also useful in producing a tracking signal that has a substantially constant amplitude over a range of track pitches. The track format, in the preferred embodiment, employs wobbled pits. The sequence in which the wobbled pits occur alternates between adjacent tracks and the offset of the wobbled pits with respect to the center line of a track remain constant regardless of the track pitch. The preferred embodiment of the track format also includes a reference pit that is used to establish the threshold detection level for the read electronics. The location of the reference alternates between tracks to reduce the effect of radial interference on the signal produced using the reference pit and thereby allow an optimal threshold level to be established.

Abstract: A silicon lithium x-ray detector has a new shape. The shape includes a front and a back. At the back, a center portion of thickness H is surrounded by a groove of depth D and an outer rim having a height h less than H.

Abstract: A semiconductor device of improved ruggedness is provided which comprises a semiconductor substrate having a region of a first conductivity type on a major surface thereof; a first base region of opposite conductivity type formed selectively within said regions of first conductivity type; a second base region of opposite conductivity type formed selectively within said first base region and having a higher impurity concentration than that of said first base region; a source region of one conductivity type formed within said first and second base regions and overlying said second base region; and a polysilicon gate electrode opposed to a channel region with a gate insulating layer interposed therebetween; wherein the second base region and the source region are formed substantially entirely within the first base region; the second base region is smaller in depth than the first base region and is formed at a distance sufficiently close to the channel region to effectively reduce parasitic resistance in the firs

Abstract: A stacked floating-gate field-effect transistor ("FET") structure suitable for memory cells in a nonvolatile memory is fabricated according to a process in which a floating-gate layer is formed on a semiconductor substrate (30), oxide (42) is formed along the sidewalls (35) of the floating gate (18) extending in the channel-length direction, and an oxide-nitride-oxide ("ONO") composite layer (44) is formed along the top of the structure, including the floating gate and the sidewall oxide. The ONO composite layer and the sidewall oxide act as an isolation dielectric between the floating gate and a control gate (20) formed on top of the ONO layer.

Abstract: A silicon-on-insulator material is formed by a method which includes the steps of forming a p-type silicon epitaxial layer, doped with boron and a higher concentration of germanium, on the surface of a semiconductor silicon substrate, forming an additional silicon epitaxial layer on the p-type silicon epitaxial layer, forming an oxide layer on the additional silicon epitaxial layer, forming an oxide layer on another semiconductor silicon substrate, forming a laminate by bringing into contact, at room temperature, the oxide layers thereby bonding together the substrates, etching the silicon substrate provided with the silicon epitaxial layers, with an isotropic etch to remove most of this silicon substrate, exposing the laminate to an anisotropic etch for this silicon substrate until the remainder of this silicon substrate is removed but only a part of the p-type epitaxial layer is removed and then exposing the resultant structure to an additional isotropic etch for the p-type epitaxial layer for a time suffic

Abstract: A material for use in a laser heterostructure which is lattice matched material to ZnSe and has a high band gap. The material is Mg.sub.y Zn.sub.l-y S.sub.x Se.sub.l-x with the ratio of sulphur to magnesium of 0.26/0.19. Lasing devices constructed from layers of this material and ZnSe can be either electron beam pumped or electrically driven.

Abstract: An axially reciprocable working piston has opposed working surfaces facing opposed working chambers which are intermittently connected to respective cavities pressurized with compressed air. The working piston is connected to opposed seating pistons which cut off the connection between the cavity and working chamber behind the advancing piston and establish the connection in front of the piston, thereby conserving compressed air and storing potential energy for return movement of the piston. In either of two stable positions the working piston is hydraulically latched by fluid admitted to a respective chamber from another chamber through a two-way check valve. The check valve is electronically switched on commend to reverse the flow direction of the hydraulic fluid, thereby initiating movement between opposed stable positions.

Abstract: A lighting system having a primary light source and an emergency lamp. The emergency lamp is turned on and remains on upon failure or removal from the system of the primary light source. The system also includes a control device for sensing when the voltage across the primary light source rises above a predetermined level in determining when to turn on the emergency lamp.

Abstract: A hydraulic actuator includes a pneumatic piston, a hydraulic piston, and an engine valve on a common shaft. The pneumatic piston is urged between first and second stable positions primarily by a double acting pneumatic spring, with high pressure hydraulic fluid connected to a first hydraulic chamber being used to cock the hydraulic piston in a first stable position (engine valve closed). Hydraulic fluid isolated in a second hydraulic chamber is used to latch the hydraulic piston in a second stable position (engine valve open). Transfer of hydraulic fluid between first and second chambers is effected by a carrier for two check valves, which carrier in a first position disables the second check valve to permit fluid to flow from the second chamber to the first chamber, whereupon the first check valve closes (cocking). In a second position the carrier disables the first check valve to permit fluid to flow from the first chamber to the second chamber, whereupon the second check valve closes (latching).

Abstract: A stepper motor of the permanent-magnet sheet-metal type is constructed of a number of modules, simplifying assembly. The modular parts include a stator having integrally-molded winding bobbins and pole pieces. A rotor mounted in the stator includes a barrier member which separates a plastic, threaded hub molded interiorly from a permanent magnet molded exteriorly. A shaft having a first threaded end rotatably engaged with the interior of the rotor hub has a rectangular central portion extending through a rectangular opening of the stator to convert rotary motion of the rotor to linear motion of the shaft. An opposite end of the shaft includes a molded head and a tubular shield extending from the head. This shield and a tubular portion of the stator molding define a labyrinthal passage which inhibits the passage of contaminants into the rotor. A housing of the motor and a rotatably attached flange include engagable portions to lock the flange at a desired angular position.

Abstract: A subscriber control system designed to be placed outside of the subscriber's home, for controlling access to cable television signals provided by a cable television headend. The system is modular in design containing a single control module and a single RF distribution module both shared by a number of jammer modules. The jammer modules contain a plurality of frequency agile oscillators, the frequencies of which can be changed in time-multiplex fashion. The outputs of the jammer modules can be shared amongst a number of subscribers using space division switching.

Abstract: A method for rapid plasma hydrogenation of semiconductor devices is provided in which the hydrogenation is conducted in two steps, the first step being conducted at a hydrogenation temperature that is higher than the out-diffusion temperature at which a substantial amount of hydrogen diffuses out of said semiconductor device; and in the second step, the semiconductor device is cooled to a temperature at which out-diffusion is substantially avoided while the hydrogenation plasma is maintained.

Abstract: A housing has a pilot bore with an electrically controlled pilot valve therein, an intermediate bore with an intermediate valve therein, and an engine bore with a main valve therein, each valve being reciprocable between first and second stable positions. When said pilot valve is switched to its first stable position, high pressure hydraulic fluid drives said intermediate valve to its first stable position and releases said engine valve from its second stable position, whereupon a double acting spring drives the engine valve toward its first stable position. High pressure hydraulic fluid completes this movement then holds the main valve in its first stable position against the force of the double acting spring. Switching the pilot valve to its second stable position effects movement of the other valves back to their second stable positions.

Abstract: A stepper motor of the permanent-magnet sheet-metal type is constructed of a number of modules, simplifying assembly. The modular parts include a stator having integrally-molded winding bobbins and pole pieces. A rotor mounted in the stator includes a barrier member which separates a plastic, threaded hub molded interiorly from a permanent magnet molded exteriorly. A shaft having a first threaded end rotatably engaged with the interior of the rotor hub has a rectangular central portion extending through a rectangular opening of the stator to convert rotary motion of the rotor to linear motion of the shaft. An opposite end of the shaft includes a molded head and a tubular shield extending from the head. This shield and a tubular portion of the stator molding define a labyrinthal passage which inhibits the passage of contaminants into the rotor. A housing of the motor and a rotatably attached flange include engagable portions to lock the flange at a desired angular position.

Abstract: An improvement in a self-passivated high voltage semiconductor device is set forth with a thinned SOI layer having a linear lateral doping region coated with an oxide layer and a field plate being a part of the gate electrode layer. A high voltage SOI semiconductor device is formed having freedom from external electric fields.

Abstract: Thin film magnetic head structure includes digital read/write heads and analog read heads integrated on a single substrate. The "wrap around pole effect" is reduced or eliminated by having the thicknesses of the digital lower flux guides and the analog read gap-defining layer approximately the same, resulting in improved signal output from the digital read heads. The structure is useful in cassette decks designed to play both digital and analog compact cassettes.

Abstract: A test pattern suitable for testing high definition (HDTV) television signals is described as well as a method and apparatus for providing such a pattern on a television display apparatus. A plurality of color signals are stored in a memory device (look-up table) and each pixel of the display screen is correlated to a point on a spiral curve in order to determine a rotational angle which is used as an address for one or more of said color signals which are displayed at that pixel location. In this manner, a spiral shaped test pattern is generated having spiral color (or monochrome) segments corresponding to a spiral curve.