Abstract: An embodiment of the present invention is an improved insulated-gate, field-effect transistor and a three-sided, junction-gate field-effect transistor connected in series on the same chip to form a high-voltage MOS transistor. An extended drain region is formed on top of a substrate of opposite conductivity material. A layer of material with a conductivity opposite to that of the material of the extended drain region is buried within the extended drain region such that field-effect pinch-off depletion zones extend both above and below the buried layer. A top layer of material similar to the substrate is formed by ion implantation through the same mask window as the extended drain region. The top layer covers the buried layer and extended drain region and itself is covered by a silicon dioxide layer above. Current flow through the extended drain is controlled by the substrate and buried layer when a voltage is applied to pinch-off the extended drain between them in a familiar field-effect fashion.

Abstract: A disk system comprising an upper and lower head gimbal assembly, a coarse positioning servo system that includes a stepper motor for 135 TPI operation and a voice coil motor type servo for 1251 TPI operation that is driven by a optical servo system which locates optical track positioning information previously recorded on 3.5 inch microfloppies. The optical system focuses a spot of infrared light on the microfloppy which is channeled back to a detector. Each head gimbal includes a ceramic slider with two air bearing surfaces. A very high density magnetic core is positioned in one air bearing surface and high density magnetic core is located in the other air bearing surface. Both upper and lower sliders are such that the floppy disk media is pinched between them. The gaps of the magnetic cores are positioned within the leading edge half of their respective air bearing surfaces and take advantage of the tendency of the sliders to plow into the floppy disk media.

Abstract: An embodiment of the present invention is a single-chip GPS receiver front-end comprising a radio frequency amplifier, a voltage-controlled oscillator operating at a first local oscillator frequency, a divide by seven and one-half counter for deriving a second local oscillator frequency from the first and a first and second mixer. The local oscillator frequency is mid-way between two carrier frequencies of interest that may be received by the radio frequency amplifier and the first mixer produces a first intermediate frequency. The second local oscillator frequency is then beat with the first intermediate frequency in the second mixer to produce a second intermediate frequency. A dual-conversion super heterodyne configuration is therefore employed in which the first and second local oscillator frequencies are derived from a single oscillator and the first local oscillator frequency is seven and one-half times the second local oscillator frequency.

Abstract: A passive semiconductor structure for reduction of the mutual capacitance between parallel conductors, with two parallel conductors separated from a substrate by a first dielectric layer and covered by a second dielectric layer. The second dielectric layer having a cavity formed between these conductors, whereby the effective relative dielectric constant of the medium between these conductors is reduced.

Abstract: A talking analog clock comprises an analog mechanical clock movement in which the minutes mechanism has attached to it a switch that opens and closes for each minute elapsed. A digital synchronizing circuit is included that senses the closing and opening of the switch and uses these events to increment a digital time-keeping circuit. A directional switch attached to a winding stem and connected to the digital synchronizing circuit allows the digital time-keeping circuit to be incremented or decremented with the winding stem. The time in the current time memory is thereafter locked in synchronization with the analog time shown on the display dial. A user can therefore set the time or an alarm time in a simple way.

Abstract: An embodiment of the present invention includes an open-ended, non-spinning housing, which is fitted with an inner lining that rotates within the housing at speeds sufficient to de-water material loaded from within and along the length of the inner liner. A loading conveyor system has a discharge end that can be relatively positioned horizontally at various depths within the inner liner to deposit product at continuously variable layer depths on the inner liner while it is spinning. Once loaded, the inner liner is accelerated to a drying speed and the housing is swiveled to vertical on gudgeons. Once drying is complete, the inner liner is slowed down, or stopped, and the de-watered product can fall out to land on an unloading conveyor.

Abstract: An apparatus of the present invention includes a viewer response system comprising a host site and at least one remote site interconnected by a satellite channel for host-to-remote video, an X.25 communications channel for message exchanges establishing a virtual circuit between each remote and the host site, and a dial-up public phone network channel that allows the host site to dial a remote site in response to a person at the remote site wanting to speak on the system to another person at the host site. A touch screen monitor at the host site allows the other person to sequence through electronic notecards that function as presentation cue cards. Questions can be formatted on remote site monitors and keypad terminals for each person at each remote site to allow real-time responses to be entered. A computer supporting the host site computes and displays remote site status and person's responses.

Abstract: A method for using an underground mine communication system to effect minewide communication and an intrinsically safe current limiter circuit for insuring that electrical equipment in the system will not cause incendiary conditions. The underground mine communication system comprises a plurality of repeaters and medium frequency radios, including mobile, portable and personal-carried radios, coupled to electrical conductors and natural waveguides existing in the earth by tuned loop antennas. Messages transmitted by the radios are carried to the repeaters by the conductors or coal seam waves. The repeaters amplify, replicate and retransmit the message at two different frequencies for transmission of the message to a surface base station and to other radios in the system. A paging system, which has a separate set of repeaters, is also coupled to the network of electrical conductors and natural waveguides by tuned loop antennas. The paging system alerts miners to contact the surface base station.

Abstract: A portable soldering device comprises a short arc lamp including an alumina ceramic cylindrically shaped body with a concave opening at one end that is plated with silver to form an ellipsoidal reflector, a cathode suspended within the concave opening in opposition to an anode protruding through a hole in the center of the concave opening from the opposite end of the body, a circular iron base that supports the anode at its center and attaches to the body. The soldering device further comprises a cone-shaped hood over the flat window and a supply of inert gas attached to the hood that excludes smoke, residue and splatter from infiltrating the hood.

Abstract: A method for comparing the relative phase of carrier signals received from GPS satellites to determine the roll, pitch and azimuth attitude of ships, aircraft, land vehicles, or survey instruments, accomplishes a maximum likelihood estimation (MLE) optimum solution over the full range of integers and vehicle attitudes. The problem is formulated as an MLE optimization, where vehicle attitude and integers are regarded as parameters to be adjusted to maximize probability of first-difference carrier phase measurements that are actually generated by hardware. Formulation results in weighted-fit error W as the objective criterion to minimize. A Kalman filter is introduced, having same objective criterion. Minimizing computation in Kalman filter leads to a decision tree for the integers. Two ways are shown to prune decision tree. The first is to exclude impossible combinations, such as those that produce an antenna upside down. The second is to generate a lower bound for W at each branch of the tree.

Abstract: A hard disk drive for a computer system including a head disk assembly with a disk platter of approximately one-and-eight-tenths-inch in diameter capable of storing more than forty megabytes. In an embodiment, data tracks on each data surface of the platter are spaced at approximately 2,558 tracks per inch and each data track has approximately 36,000 flux changes per inch. An actuator positions a pair of read/write heads on each platter surface using a voice coil motor to position the heads over a cylinder. A magnetic actuator latch attaches to another magnet on the actuator and locks the heads in a parked position at the innermost diameter of the platter. A spindle motor rotates the platter at approximately 5,400 revolutions per minute. A base plate, with a gasketed surface and a raised lip, hermetically seals with a cover to the base plate such that the platter, the actuator, the actuator latch, and the spindle motor are all contained within. The cover carries a breather filter and recirculating air filter.

Abstract: An embodiment of the present invention is a switching power supply comprising a transformer with a primary and two secondaries, a switching transistor in series with the primary, a rectifier and filter on one secondary to provide regulated output power, a feedback control circuit that monitors the secondary and adjusts the duty cycle of an on-off control signal to the switching transistor to maintain a constant output at the terminals, and a monitor that detects when the power level flowing through the switching regulator has dropped to a predetermined minimum and then linearly turns on a load to the transformer. Transistor is typically a power MOSFET. The monitor tracks a summing junction current before any slope compensation is added. Load is a shunt regulator that is activated when the summing junction current falls below 12% of full scale. Alternatively, the predetermined value of 12% is adjustable.

Abstract: An embodiment of the present invention is a semiconductor fabrication process that deposits an oxide layer after a step to make contact openings in a BPSG layer and before a contact reflow step. The oxide allows implant dopants to be properly activated in the contact reflow step without excessive reflow of the BPSG.

Abstract: An embodiment of the present invention is a switching power supply that includes a full-wave bridge rectifier to rectify incoming AC line voltage, a transformer having a primary winding and two secondary windings and a switched mode power supply chip that includes an integrated high voltage power MOSFET with a low voltage tap in the drift region. The MOSFET controls power switching of the primary winding of the transformer and has a high voltage present during initial power-up. This high voltage is dropped across the JFET part of the MOSFET and supplies a regulator with power either temporarily or continuously to operate a pulse width modulator in the chip that controls the switching of the MOSFET.