Abstract: A system and method of automatically calibrating a vehicle speed sensor signal to provide an accurate speed signal for use in vehicle systems such as a navigation system. The navigation system receives GPS position information signals which are processed to determine current position. A compass provides an indication of the vehicle heading. The navigation system receives the vehicle speed sensor signal and counts the number of signal pulses during a time period. The system determines a pulse ratio of the vehicle speed sensor as a function of a GPS determined speed and the pulse count. The pulse ratio is subsequently used to calibrate the vehicle speed sensor signal. With the navigation system, the calibrated vehicle speed signal is used in connection with a dead reckoning technique for determining the position of the vehicle when GPS signals are unavailable.

Abstract: A frequency synchronization network is disclosed that is particularly suited for a Eureka-147 system transmitting synchronization symbols and multiple data carriers, wherein the multiple carriers are transmitted simultaneously and separated from each other by a bin quantity. The network comprises a Fast Fourier transform (FFT) network, a complex rotation device, and a power analyzer. The power analyzer determines the peak condition of the FFT bin quantities and routes this information to an interpolation sequence that determines the zero-crossover condition of the peak bin quantity, and which ultimately determines an output as the frequency offset of the AFC frequency symbol. The frequency offset quantity is provided to an automatic frequency control (AFC) network to provide for frequency locking of the transmitting and receiving elements of the Eureka-147 system.

Abstract: A differential demodulator that is particularly suited for a digital audio broadcasting (DAB) system, and more particularly to the Eureka-147 (DAB) system, is disclosed. The differential demodulator of the present invention receives complex data components I and Q derived from a fast fourier transform operation and converts the data components I and Q into differential data components .DELTA.I and .DELTA.Q that are accepted by data demodulating elements of the Eureka-147 system so as to be reconstructed as digital data which, in turn, are converted into an analog form that is converted and reproduced into corresponding high quality sound. The conversion of I and Q data into .DELTA.I and .DELTA.Q data is accomplished via a network of four ROMs and one RAM, wherein the ROMs are time-shared between the multiple carriers of the Eureka-147 system.

Abstract: An automotive ignition control system includes a vehicle control computer operable to provide electronic spark timing (EST) signals, a control circuit having a number of coil drive circuits connected thereto, a corresponding number of coil driver devices connected to respective ones of the coil drive circuits and a corresponding number of ignition coils connected to respective ones of the coil driver devices. The control circuit is responsive to an active state of any one of the EST signals to activate a corresponding one of the coil driver devices while inhibiting activation of all others. If any EST signal remains in an active state for an excessive time period, the control circuit is operable to lock-out the corresponding coil driver device from operation until such a fault condition is cleared. The control circuit is preferably operable to accomplish the lock-out function by gradually decreasing the coil current associated with the faulty EST signal in a fashion that does not generate a spark event.

Abstract: A microprocessor-based control for a solenoid operated device, wherein the microprocessor employs a tri-state output to achieve fast, precise control of the device without overburdening the microprocessor. The system has three selectable control modes: a first control mode in which the solenoid is de-energized, a second control mode in which the solenoid is fully energized, and a third control mode in which the solenoid is pulse-width-modulated. The various control modes are selected by the microprocessor and indicated by the logic level of a tri-state output. In the first and second control modes, indicated by first and second logic levels, the energization state of the solenoid is controlled directly by the microprocessor. In the third control mode, indicated by a third logic level, the energization state of the solenoid is controlled by an external PWM circuit based on PWM commands supplied to the PWM circuit by the microprocessor.

Abstract: A temperature sensing system for sensing ambient temperature around a vehicle. The sensing system includes a temperature sensor, such as a thermistor or thermocouple, positioned within the antenna finial of a fixed-mast antenna of the vehicle. A sensor signal from the sensor is applied to a sensor circuit that includes suitable filtering components. The filtered sensor signal is then applied to a microcontroller where the signal is processed to display the exterior temperature on display within the vehicle passenger compartment. A sensor lead and a return lead are wrapped around the mast antenna to transfer the sensor signal from the sensor to the sensor circuit. The mast antenna is wrapped with a shrink-type tubing or covered with an epoxy-type coating to cover the sensor lead and return lead. The presence of the wires provides the added benefit of reducing wind noise traditionally associated with the antenna mast.

Abstract: Composite solder paste compositions adapted to be deposited using a dry film photoresist mask to form solder joints for flip chip integrated circuit devices. The composite solder paste compositions are characterized by the ability to flow at a first temperature during bumping reflow while the photoresist mask is present, yet upon subsequently reheating to a higher temperature yield solder joints capable of withstanding temperatures of 200.degree. C. and higher. As such, the present invention retains the advantages associated with using a dry film photoresist as a mask during deposition of the solder, yet results in the formation of solder joints that exhibit enhanced reliability in severe thermal environments.

Abstract: A pressure sensor comprises a diaphragm mounted on a housing and subject to pressure. Stress sensitive resistors are connected to circuit traces on the diaphragm which in turn are wirebonded to a compensation IC. The IC is directly mounted on the diaphragm principally or wholly in an area which is not subject to flexing. A connector has a dome partially covering the diaphragm and holds terminal blades having ends extending away from the diaphragm and opposite ends carrying bond pads located adjacent the diaphragm. An opening in the dome permits wirebonder access to connect bond pads on the traces with terminal bond pads. A cover is installed over the connector and sensor.

Abstract: A firing circuit for multiple vehicle passenger restraint initiators, wherein initiators located in proximity to each other are paired in first and second parallel connected firing loops terminated by first and second firing circuit nodes. The first firing loop includes one of the initiators and a first diode poled to conduct current from the first node to the second node, and the second firing loop includes the other initiator and a second diode poled to conduct current in the opposite direction, that is, from the second node to the first node. A switching circuit, such as a four-element bridge couples each pair of firing loops to a source of DC so that the source voltage can be applied to the firing loop nodes in either polarity, depending on whether the switching circuit receives a first firing signal or a second firing signal.

Abstract: A memory cell having programming voltage margin verification is provided. The memory cell includes a voltage comparator having a differential input with first and second inputs and bias circuitry for generating a differential input voltage. A voltage offset is applied to the second input of the comparator to provide an input offset voltage. A programming voltage is received for programming the memory cell and the memory cell provides an output signal. To verify an unprogrammed state voltage margin of the memory cell, a margin detection circuitry receives a verification check signal and the output is monitored to determine whether the unprogrammed state voltage margin is proper. To verify a proper programmed state voltage margin of the memory cell, current is sensed through the programming input and a determination of a proper programmed state voltage margin is determined as a function of the sensed current.

Abstract: In accordance with the teachings of the present invention, a programmable integrated transducer amplifier circuit is provided which receives differential outputs from a transducer, such as a pressure or accelerometer transducer. The programmable integrated transducer amplifier circuit includes binary adjustable circuits that are programmed in response to binary coded signals. The binary adjustable circuits generate binary weighted currents that are employed to adjust the operating characteristics of the amplifier circuit. The binary coded signals are received from a programmable memory array which includes a plurality of memory cells that store binary information. Each of the memory cells are programmed when coupled to a programming signal. Additionally, the memory array has pretest capability for testing outputs of the memory cells prior to permanently programming the respective memory cells.

Abstract: A coil is wound on a bobbin having posts extending from the bobbin body, the end of the coil wire being wrapped on the posts to form wire terminations. The coil is mounted on a circuit board with the coil either above the board or suspended alongside the board edge. The periphery of each post is positioned against a solder pad of the circuit board and the wire termination is soldered to the pad. Each post has a flexible neck portion to relieve stress due to coil thermal expansion. A recess in the side of the post facing the solder pad enhances solder interaction with the wire termination.

Abstract: A flow control device for a solder wave apparatus that includes an outlet or nozzle from which molten solder flows in an upward direction to contact the lower surface of a target, such as a circuit board. The flow control device provides a screen and baffle that control the flow pattern of molten solder to the nozzle so as to result in a near-parallel solder wave above the nozzle. The screen includes a pair of spaced-apart parallel panels that are disposed upstream of the nozzle. Each of the panels has apertures through which the molten solder flows before entering the nozzle. The apertures of the panels are offset from each other, such that none of the apertures are coaxial but instead overlap each other when superimposed. The baffle is disposed further upstream of the screen, and includes a number of fins disposed substantially perpendicular to the panels. The fins are arranged such that their lengths become progressively shorter in a direction away from the center of the baffle.

Abstract: A digital phase-lock loop network that provides input and output clock signals to a digital data receiving system generally, and particularly to a data buffer contained therein, is disclosed. The digital phase-lock loop network provides bit-clock synchronization using a fixed input clock and an output clock having a variable frequency that is adjusted to correspond to the average input rate of the data samples into the data buffer. The digital phase-lock loop network allows the data buffer to be operated as a temporary storage device maintaining a nominal number of data samples therein at all times by avoiding any overflow and underflow data handling conditions that may otherwise cause loss of data. The digital phase-lock loop network of the present invention is particularly suited for the Eureka-147 system which has become a worldwide standard for digital audio broadcasting (DAB) technology.

Abstract: A backlite antenna system for an AM/FM vehicle stereo where the antenna system includes an antenna grid embedded in a rear window of the vehicle, that is electrically separate from a heater grid embedded in the rear window. The antenna grid includes a plurality of equally spaced, horizontal antenna elements that extend almost the entire width of the rear window of the vehicle. Two vertical end bus bars and two vertical center bars connect the antenna elements. An FM tuning stub is connected to the antenna elements for appropriate FM reception depending on the type of vehicle body. An antenna module housing a matching circuit, and possibly an amplifier circuit, is located in the header of the vehicle adjacent to the vehicle window.

Abstract: A synchronization network that provides frame timing that is particularly suited for a Eureka-147 system is disclosed. The synchronization network reduces the typical amount of computations required to provide for frame timing schemes and includes matched filtering operations that separate the waveforms of null and sine symbols contained in the multiple carriers of the Eureka-147 system. The matched filtering technique are accomplished before a fast Fourier transform operation and which accomplishments elimination of the need of an inverse fast Fourier transform operation normally performed by one of the receiver elements of the Eureka-147 system. This elimination is accomplished without degrading the performance of the Eureka-147 system.

Abstract: A high frequency AC probe signal is applied to one coil of a stepper motor to induce a signal on the other coil. The induced signal varies in amplitude according to rotor position. The stepper motor is driven by a microprocessor in microsteps. The position of a mechanical stop is determined by monitoring the induced signal while driving the rotor to the stop. When the induced signal no longer changes in amplitude the number of the last microstep yielding movement is recorded as the rotor position corresponding to the stop position. Also by measuring the induced signal at each microstep over a whole rotor rotation and the signal when the rotor stops, a more precise value of the stop position is determined by interpolation. Alternatively, the flip back position of the gauge and thus the stop position is determined on the basis of the induced signal.

Abstract: An apparatus and method for attaching an electrical component to a convector attached to a chassis of an electrical package is disclosed. The convector comprises one or more slide tracks adapted to receive a spring clamp that provides the sole means for securing a heat-generating component to the convector. The spring clamp includes a flange adapted to be grasped for insertion into the slide tracks, and adapted to cover an opening in the chassis. The spring clamp also includes a pair of prongs, each adapted to fit within one of the slide tracks, and spaced apart from one another so as to capture a rectangular protrusion on the convector therebetween when inserted into the slide tracks. Each prong preferably includes a locking hook that engages the rectangular protrusion.

Abstract: The ignition coil driver module of the present invention includes a control integrated circuit and a high current load driver integrated circuit housed within a common package such as a TO-247 or TO-264 package. The control integrated circuit is formed of a semiconductor material manufactured in accordance with a standard low-voltage integrated circuit processing technology and is responsive to a control signal input to provide a low voltage drive signal. The high current load driver integrated circuit is formed of a semiconductor material manufactured in accordance with a high-voltage integrated circuit processing technology and is responsive to the low voltage drive signal to energize the high current load. A current limit function is further provided for limiting the load current to a predetermined level.

Abstract: Thin circuit pathways of an electronic circuit are integral with thick terminal pins. The thin and thick portions are stamped, formed and chemically etched from a single sheet of copper or copper alloys, and mounted on a substrate to eliminate the need of a separate header. Components are soldered to the thin pathways in the conventional manner and a housing is molded to the circuit or a preformed housing is attached to the circuit. In another embodiment, a filtered header which contains thin circuit pathways integral with thick terminal pins is formed in the same manner and includes filtering components.