Abstract: Speech synthesizer and a computer system having the speech synthesizer operably coupled thereto to provide speech capability for the computer system. The speech synthesizer is capable of electronically synthesizing human speech from coded speech data including parameters as stored either in a solid state memory on a permanent basis or alternatively as temporarily stored in another memory, wherein the coded speech data is made available from an external source, such as a central processing unit of a commercial or home-type computer, as coupled to the speech synthesizer.

Abstract: Power-up clear circuitry includes a latch which powers-up in a preferred state. Threshold detect circuitry changes the state of the latch when the supply voltage reaches its operating value, and then switches itself off. Transient protection circuitry ensures that the latch properly powers-up in the preferred state after a supply transient which drops below the threshold voltage of the circuit devices.

Abstract: A microcomputer device contains a CPU with an arithmetic/logic unit and data/address registers on a single semiconductor integrated circuit having on-chip macrocode and microcode storage. In the normal single-chip operation mode, a macrocode word is fethched from on-chip ROM and stored in an instruction register in the CPU, then a sequence of microcode words is fetched from the microcode store based on this macrocode word. In another mode, such as used for self-test employing a check-code, the device loads macrocode from external into on-chip RAM then executes from RAM to perform the desired routine, switching modes of operation.

Abstract: A thermal energy imaging system includes an optical system for focusing thermal energy emanating from a scene on an array of bulk semiconductor photodetectors. The detector array outputs electrical signals representative of the impinging thermal energy, a video electronic circuit and a pseudo ac coupling circuit interconnecting the detector array and video electronic circuit for reducing the required dynamic range of the video electronic circuit. The pseudo ac coupling circuit includes first and second electrical paths to an sychronous clamp. The first path includes a switch to the synchronous clamp; the second clamp includes first and second integrator circuits and a switch; the switch is connected to the synchronous clamp. The synchronous clamp includes an amplifier, capacitor and grounded switch.

Abstract: Polysilicon resistors and integrated circuits are brought to zero or positive temperature coefficient (TCR) by a combination of laser annealing and ionic hydrogen plasma treatment.

Abstract: The present invention teaches a new method for formation of thin dielectrics over polysilicon. This technique permits the fabrication of polysilicon to polysilicon capacitors with high specific capacitance (per unit area). This technique is completely compatible with standard MOS dual polysilicon regrown gate oxide processes. The high value of specific capacitance is achieved by using a composite dielectric which has high dielectric integrity and whose thickness is completely independent of the formation of the regular gate oxide under the second polysilicon layer. No extra mask steps are required. The composite dielectric is formed as a grown or deposited oxide followed by deposited nitride which is then reoxidized. Optionally, a second oxide is deposited before reoxidation forms.

Abstract: This specification discloses a CCD imager which includes a line addressing circuit (24) which selectively addresses CCD imaging gates (48). Output signals are clocked under the gates (48) to a buffer register (30) which is constructed in the form of a tree. Signals from under each of the CCD gates (48) travel an identical length path through the buffer register (30) to a charge detection circuit (46) measured by the number of pixels involved. The output signals thus take the same time, or same number of clock pulses, to travel the length of the buffer register (30) to enable all line switching to be accomplished during the horizontal blanking time of a television thus eliminating the switching noise from the television screen.

Abstract: The present invention teaches a process for fabrication of quantum-well devices, in which the quantum-wells are configured as small islands of GaAs in an AlGaAs matrix. Typically these islands are roughly cubic, with dimensions of about 100 Angstroms per side. To fabricate these, an n- on n+ epitaxial GaAs structure is grown, and then is etched to an e-beam defined patterned twice, and AlGaAs is epitaxially regrown each time. This defines the quantum wells of GaAs in an AlGaAs matrix, and output contacts are then easily formed.

Abstract: A system for real-time digital signal processing employs a single-chip microcomputer device having separate on-chip program ROM and data RAM, with separate address and data paths for program and data. An external program address bus allows off-chip program fetch in an expansion mode, with the opcode returned by an external data bus. A bus interchange module allows transfer between the separate internal program and data busses in special circumstances. The internal busses are 16-bit, while the ALU and accumulator are 32-bit. A multiplier circuit produces a single state 16.times.16 multiply function separate from the ALU, with 32-bit output to the ALU. One input to the ALU passes through a 0-to-15 bit shifter with sign extension.

Abstract: A dynamic read/write memory device using one-transistor N-channel silicon gate type cells is made by a double-level polysilicon process in which the field oxide is of reduced thickness for the cell array, and of conventional thickness for peripheral circuits. This reduces moat encroachment in the critical cell portion, yet does not force performance compromises in the critical speed paths.

Abstract: Disclosed is a unidirectional interdigitated surface wave transducer having at least three discrete arrays of conductive elements, each array comprising, in a comb-like structure, a plurality of electrodes electrically interconnected in parallel and having a periodicity corresponding to one acoustic wavelength of the resonance frequency of the transducer. The discrete arrays of electrodes are deposited upon a piezoelectric substrate in an interleaved pattern to define an interdigitated transducer. Respective electrodes of a given array are substantially equidistantly spaced apart from electrodes of the other arrays and are electrically insulated therefrom. The arrays of electrodes are positioned upon the substrate such that there are at least three electrodes per acoustic wavelength at the resonance frequency.

Abstract: A method for plasma etching of TiO.sub.2, using a mixture of oxygen and a fluorine-bearing species, preferably CF.sub.4. This mixture gives good selectivity over aluminum and photoresist, and approximately unity selectivity over silica or silicon nitride. Use of a chlorine-containing species is also taught by the invention, and will provide different selectivities. The present invention is also useful for etching in the RIE mode.

Abstract: Bipolar transistors and other electronic structures are fabricated on a gallium arsenide (GaAs) substrate to form an integrated circuit device. This integrated circuit device is made possible by development of an ion implant technique which uses an acceptor material to create a P type region, boron or protons to create insulating regions, and silicon or selenium to create an N type region. The use of an ion implant technique avoids the difficult problems encountered in diffusion methods, and, due to the precise control available with ion implantation, makes possible the fabrication of IC quality transistors consistently over a substrate. This same control enables the fabrication of integrated circuits with improved device packing density and reduced parasitic parameters.

Abstract: An electronic flame off (EFO) electrode used to form balls on bonding wire builds up layers of aluminum oxide during use. The aluminum oxide is removed by moving the EFO electrode next to a cleaning electrode, and causing a glow discharge to pass across the gap between them. The EFO electrode is charged negative with respect to the cleaning electrode, and a noble gas, such as argon, fills the region around the gap.

Abstract: A method for optically marking selected integrated circuit bars of visual identification. In one embodiment a layer for photosensitive material applied to a portion of all of the bars on a wafer prior to testing. Selected bars are marked by directing a beam of radiant energy at the photosensitive material, which changes opacity and/or color in the irradiated region.

Abstract: An image projection system for producing a projected image in response to electrical signals which represent the image to be projected. The projection system includes input capability to produce electrical signals in response to an image to be projected. These electrical signals are then transmitted to a light modulator which receives light from an external source. The light modulator consists of arrays of deformable mirrors which selectively deflect the light from the external source in response to the electrical signals received from the input capability. The deflected light is absorbed by opaque stops. The undeflected light travels through optics which form the projected image. A printer using this image projection system is also disclosed. The printer further includes the ability to develop the projected image in such a manner that the image is transferrable to a paper surface in a printer in such a manner that the image is reproduced upon the surface in a printer form.

Abstract: A microprocessor device with an on-chip integrated auto-loaded timer is used in an adapter for a communications loop of the token-passing local area network type. The network has a number of stations coupled to a closed one-way signal path, and each station has a host processor with a host CPU and memory. The microprocessor device with integrated auto-loaded timer is part of an adapter coupled to the host processor. A message frame to be transmitted is copied into a local read/write memory in the adapter by way of the host system bus and a local bus, under initiation by the host CPU. A transmit-and-receive controller is coupled to the local bus to directly access the local read/write memory; when this station has access to the loop (i.e., receives a free token) the transmit-and-receive controller copies the message frame from the local read/write memory to the outgoing signal path, converting from parallel to serial.

Abstract: A PSK integrated circuit modem employs multi-mode filters in its switched capacitor circuitry for providing a plurality of filter response to accomodate a plurality of modem protocols. Each capacitor is selectively connected or disconnected from the circuit by a transistor switch, and selectively connected and disconnected from the circuit voltage reference by a transistor switch. The switches operate out of phase with each other so that when any capacitor is connected in the circuit, it is disconnected from the reference voltage and when any capacitor is disconnected from the circuit, it is connected to the reference voltage. The modem switch minimizes the effect of stray capacitance from the unselected capacitors and their associated transistor switches that have been turned off.

Abstract: A thermal energy detecting system includes a closed cycle cooler (refrigerator) having a piston assembly including a piston, a piston housing and a preloaded spring mounted in the piston housing between the head of the piston and the piston housing for substantially reducing any bearing clearances of the piston assembly during the pressure changes occurring above and below the piston during the cooling cycle of the cooler.

Abstract: A cylinder pressure transmitter has means mounting piezoelectric means to provide an electrical signal corresponding to the pressure of a cylinder of an internal combustion engine and has electronic means on the mounting means to amplify the signal for transmission to computer control means for regulating engine operation to improve performance. The electronic means are mounted on an insulating substrate which is secured to a rigid support in a housing. Contact means, guide means, and locating means provided on the housing and on the mounting means cooperate to mount the housing on the mounting means to provide reliable interconnection between the electronic and piezoelectric means and to retain the interconnection even when subjected to engine vibrations.