Abstract: A power supply circuit impresses a signal supplied by a pulse generator (28) at one frequency on an alternating current such as a standard AC signal at 115 volts RMS and 60 hertz by utilizing a single switching transistor (Q1) coupled between the pulse generator (28) and a current-directing element (14) which, in turn, is serially coupled between a source (10) of the alternating current and a load (18). The resultant bidirectional output voltage across the load (18) may be rectified and averaged to produce a substantially constant DC voltage whose level is regulatable by controlling the duty cycle of the pulse generator (28).

Abstract: A programmable microcomputer controlled alarm clock has a multi-key input keyboard for setting the time of day, the month and date, and the alarm times of two or more independent alarms. Each alarm may be set to generate an alarm signal at a selected time on each day of two to six consecutive days of a seven-day period, the alarm sequence being automatically repeated each following seven-day period. In the normal operational mode, time of day is displayed until a month-and-date switch, an alarm-period or doze switch, or an alarm-enabling switch is actuated to display the respective date and alarm time. After the particular switch is actuated and the appropriate time information displayed, the clock returns to display time of day within several seconds.

Abstract: This invention relates to a structure for testing the integrity of a printed circuit board test fixture and to a method for implementing the verification of the fixture.

Abstract: A transistor logic tristate output device with plural phase splitter transistor means coupled in parallel configuration jointly to control sinking of current by the pulldown element with only one of the plural phase splitter transistor means coupled to control sourcing of current by the pullup element. In a preferred embodiment dual phase splitter transistors define a relatively low resistance path from high potential for controlling the pulldown element and a relatively high resistance path from high potential through the enable gate restricting power consumption in the high impedance third state.

Abstract: An electronic system for testing an electronic device responsive to a data clock signal and to a serial input data signal synchronous with the data clock signal comprises an oscillator for generating oscillator pulses, a data clock signal generator responsive to oscillator pulses for generating the data clock signal, timing circuitry for counting oscillator pulses and for generating at least one input select signal indicative of the number of oscillator pulses counted, and multiplexing circuitry for receiving at least two parallel input data signals and for sequentially selecting the parallel input data signals in response to the input select signal or signals to generate the serial input data signal.

Abstract: A metal-semiconductor field-effect transistor is formed by providing a blanket layer of the same conductivity type as the semiconductor body, with field oxide subsequently being grown, and with a region of opposite conductivity type being formed to extend partially under the field oxide, the initial blanket layer acting as the field implant region of the field-effect transistor.

Abstract: An ignition control system typically used with an automobile engine provides tight feedback control on engine timing. An integrator produces a waveform which is typically dual-slope in response to a timing signal supplied by a sensor responsive to rotation of a distributor. A dwell-control circuit produces a dwell-control reference signal which varies with the integrator waveform voltage at low engine speed. A comparator generates an output drive-control signal when the integrator waveform voltage equals or is less than the dwell-control reference voltage. An output drive circuit produces an activation signal in response to the drive-control signal to activate an output drive circuit which then supplies an ignition signal to an ignition coil. A feedback loop between the output drive circuit and the output drive-control circuit causes the output drive circuit to stabilize at a selected state such as a specified output current level.

Abstract: A compact bistable semiconductor memory cell usable in static electronic information storage devices includes a field-effect transistor merged with a bipolar transistor for storing a binary information bit.

Abstract: A plurality of charge-coupled device shift registers or shift register elements is used to generate a plurality of packets of charge, each proportional to a different reference potential. Using a sense amplifier or comparator, each of the packets of charge is compared, either simultaneously or sequentially, with one or more packets of charge generated by the potential of an analog signal. Signals from the comparator are then supplied to an encoder or a counter to generate a digital signal representative of the analog signal. In one embodiment the plurality of different reference potentials are generated by positioning the shift registers or shift register elements at various locations along a resistance having a potential applied across it.

Abstract: Read-only memories are manufactured to include the associated microprocessor controlling program specified by, and proprietary to, the manufacturer's customers. The problem the manufacturer has of identifying each ROM and associated microprocessor with each customer is now overcome by including an assigned customer identification number in a separate small permanent register that may be read out into the data bus by an appropriate input signal. Stored program security is provided by including in the ROM test circuit a fusible link that may be opened by an appropriate signal to prevent all future readout of the customer's proprietary program.

Abstract: A semiconductor memory cell comprising first and second bipolar cell transistors cross-coupled by the inverse transistor action of third and fourth bipolar transistors. Each cross-coupling transistor is formed by a single emitter diffusion in an existing common base region of one cell transistor, above a common buried collector region of the same cell transistor. The use of cross-coupling transistors eliminates the need for a direct ohmic connection to the buried layer collector, thereby simplifying layout and reducing memory cell size.

Abstract: A TTL transistor logic tristate output device particularly suitable for common bus applications including transistor and diode means for feedback of a portion of current from any output load and from stray capacitances to drive the pulldown element to greater conduction and accelerate sinking of current from the output to ground during transition at the output from high to low potential, said transistor means also arranged to block paths from the output to ground through the enable gate when the output is in the high impedance third state. Means for blocking current flow from the output through the device to high potential is also described.

Abstract: A method for forming a shaped buried layer in a semiconductor structure includes the steps of removing a portion of semiconductor material from adjacent the surface of the semiconductor substrate to form an indentation, introducing a dopant into the surface of the indentation to form regions of impurity in the semiconductor substrate, forming a region of epitaxial material on the surface of the indentation, and forming regions of insulating material to surround the epitaxial material.

Abstract: As a cassette holding wafers in an etchant bath is rotated, nitrogen gas is bubbled through the cassette adjacent the wafers to agitate the wafers, so as to ensure that etchant reaches all edge portions of the wafers.

Abstract: In a transistor circuit a linear relationship between V.sub.BE and temperature is obtained by using high base sheet resistivity devices, such as super beta NPN transistors, or lateral PNP transistors. Alternatively, high base sheet resistivity devices are fabricated having a non-linear V.sub.BE vs. temperature relationship that is matched to the non-linear V.sub.BE vs. temperature relationship of NPN devices and/or the non-linear resistivity of diffused resistors over temperature, such that the sum or difference of the non-linear terms will exactly cancel, providing a linear voltage vs. temperature relationship for the circuit as a whole.

Abstract: An electronic device comprises separate channels for receiving input signals representative of an undesired signal and a composite signal, envelope detectors for detecting amplitude envelopes of signals representative of the input signals, and an electronic subtractor for determining the electronic difference between the envelope signals to produce an output signal indicative of a desired signal. The device is employed particularly for cancelling the effect of the telephone sidetone signal in a telephone to yield an output signal indicative of the telephone maintone signal.

Abstract: A low-cost watch band and case comprises a receptacle for receiving a watch module, switch protuberances integrally formed with the sidewall of the receptale for actuating function switches on the watch module, and a watch band integrally formed with the receptacle for attaching to the user's arm.

Abstract: An electronic memory comprises a plurality of memory cells arranged in an array of rows and column, row address circuitry, column address circuitry, circuitry for sensing the logic states of the cells, and circuitry for delaying addressing of a selected column until after an addressed row has achieved a voltage level suitable for the sensing circuitry to sense. By so delaying the addressing of the selected column, the time required to read information out is reduced substantially--typically by a factor of two for a 1K or 2K.times.8-bit static memory.

Abstract: Two-point diagonally opposite electrical connection between the surface area forming a lead-receiving hole of one electrical device and the corresponding resilient lead of another electrical device is maintained by an eccentric pin inserted into holes in the two devices.An electrically conductive spring for interconnecting lead lines on a printed circuit board comprises a resilient main body for insertion into a hole in the printed circuit board, retaining protrusions integral with the main body for keeping it in the hole, and resilient arms extending outward from the main body for contacting selected lead lines.An electrical cord is anchored to a stiff sheet using a cantilevered door continuous with the sheet, the door opening having a notch for receiving the cord and, in association with the door, for holding the cord as it passes through the door opening.

Abstract: An electronic control system for controlling the duration of operation of repetitively activated equipment produces a control signal from input signals representing the values of parameters related to the duration of operation. Timing signals generated from repetitive signals produced by the equipment are digitally shifted through a delay line at a rate determined by the control signal to establish the duration of operation of the repetitively activated equipment. The equipment may include a plurality of repetitively activated mechanisms, such as fuel injectors, which are sequentially selected and activated for the specified duration of operation.