Abstract: A circuit structure and method for conducting heat from a power flip chip. Heat is dissipated from a flip chip mounted to a PCB by conducting heat through conductive vias to the opposite surface of the PCB. The flip chip is equipped with two sets of solder bumps, one of which is registered with conductors on the PCB, while the second is registered with a thermal conductor layer on the PCB surface and electrically isolated from the conductors. A second thermal conductor layer on the opposite surface of the PCB contacts the vials, such that heat is conducted from the flip chip to the second thermal conductor layer through the second set of solder bumps, the first thermal conductor layer, and the conductive vias. A heatsink is embedded in the PCB between the vias and the second thermal conductor layer to further promote heat conduction away from the flip chip. Heat can be conducted from the PCB with a second heatsink, such as a housing that encloses the PCB.

Abstract: A process and circuit board assembly by which a single soldering operation produces a multicomponent stack capable of dissipating heat from a power IC chip (12) mounted to a substrate (10). The circuit board assembly generally includes a number of conductors (16) on the substrate (10), with the conductors (16) being spaced apart and substantially parallel to each other. A heat spreader (14) is soldered to at least some of the conductors (16), and the chip (12) is soldered to the heat spreader (14). With this structure, heat is conducted from the chip (12) through the heat spreader (14) and conductors (16) to the substrate (10). To maintain proper orientation of the components (12, 14, 16) relative to each other during a single soldering operation, the components (12, 14, 16) are equipped with complementary features.

Abstract: An improved deployment method for a vehicular supplemental restraint system, wherein the existence of a rough road condition is indicated if a measure of crash severity obtained from an acceleration sensor exceeds a rough road threshold and the crash event reset criteria are subsequently met with no intervening deployment of the restraint device. The rough road indication is maintained for a timed period, and normal deployment of the restraint device is inhibited during the timed period unless the acceleration signal exceeds a minimum threshold and the measure of crash severity exceeds an additional deployment threshold which is initially higher than the normal deployment threshold. When the rough road condition is detected, a counter is initialized to a predefined value, and then periodically indexed so long as no potential crash event is in progress. If the counter is indexed to another predefined value prior to another rough road detection, the rough road condition is reset.

Abstract: An improved dual voltage automotive electrical system in which low voltage loads are powered by a series resonant DC-DC converter operated at a fixed switching frequency below the resonant frequency of its tank circuit. With this arrangement, the converter provides a fixed conversion ratio from the regulated upper system voltage, and operates with the beneficial attributes of zero current switching and inherent overload protection. In a first embodiment, a transformer inductively couples the converter tank circuit to the low voltage loads, providing full input/output galvanic isolation. In a second embodiment, the converter is configured so that a portion of the power supplied to the low voltage loads is directly coupled from the upper system voltage source, with the remaining portion being coupled through the converter.

Abstract: In a preferred embodiment, an electronic power device heatsink clamping system, including: a heatsink; at least one electronic power device disposed adjacent a side of the heatsink; at least one clamping spring, having first and second ends, disposed so as to press the at least one electronic device against the side of the heatsink; and a pressure enhancing member pressing against the at least one clamping spring, intermediate the first and second ends, causing the clamping spring to act as a simple beam spring.

Abstract: A recirculating driver control circuit for an electrically operated device has a power supply and a controller coupled to the power supply and the device. The controller generates an on/off signal through a first output. The on/off signal has an ON state and an OFF state. The controller generates a pulse width modulated signal through a second output. The pulse width modulated signal has a first state and a second state. A first switching device is coupled to the first output of the controller and the device and receives the on/off signal. The first switching device conducts when the on/off signal is in the ON state. A second switching device is coupled to the second output of the controller and the electrical device. Energy is supplied to the device when the pulse width modulated signal is in the first state and the on/off signal is in the ON state. The device recirculates energy to power supply when the pulse width modulated signal is in the second state and the on/off signal is in the ON state.

Abstract: A composite conductor for contacting a semiconductor device chip. A durable substrate subassembly for a high power transistor switching modules. The substrate subassembly is durable because wire bonds to the semiconductor device electrodes are replaced with a soldered metal/ceramic composite conductor. The part of the composite conductor contacting the semiconductor device has a coefficient of thermal expansion close to that of the semiconductor device. The substrate in the substrate subassembly has automatic alignment features. The composite conductor also has automatic alignment features, along with stress relief features. Automatic alignment permits concurrent soldering of the chip to the substrate, and the composite conductor to the chip and to a terminal contact.

Abstract: A capacitive pressure sensor that uses polysilicon as an electrostatic bonding medium and as a lead transfer to make an electrical connection to an electrode within a vacuum sealed chamber. The heavily doped P++ region of a silicon wafer defines a movable diaphragm that is bonded to a glass substrate of the sensor. The diaphragm is one electrode of the capacitor and includes a recess that defines the sealed chamber. An internal electrode is patterned on the glass substrate in the sealed chamber, and is the other electrode of the capacitor. An internal lead within the chamber is electrically connected to the internal electrode and a polysilicon layer that seals the diaphragm electrode to the glass substrate. Dielectric isolation layers are provided to electrically isolate the polysilicon sealing layer in the diaphragm electrode, and isolate the polysilicon sealing layer from an etchant that removes a polysilicon region around the diaphragm electrode during fabrication.

Abstract: A damage resistant control, including: a first shaft; a second shaft having its proximal end attached to control apparatus; and adapter apparatus connecting the distal end of the first shaft and the distal end of the second shaft such as to permit a degree of axial movement between the first shaft and the second shaft so as to isolate axial force applied to the first shaft from being transmitted to the second shaft.

Abstract: In a preferred embodiment, an integrated switch pad-aspirated sensor shroud for a vehicle climate control system, including: a switch pad including a base member; an opening defined through the base member through which opening ambient air may be drawn to flow across a temperature sensing element; a hinge member formed of one piece with the base member and extending therefrom; a sensor shroud formed of one piece with the hinge member, the sensor shroud being configured to provide a flow path for the ambient air; and the sensor shroud being attachable to a first element of the vehicle climate control system.

Abstract: An improved weight estimation apparatus in which a closed, multiple cell elastomeric bladder filled with fluid is installed in the foam cushion of a vehicle seat bottom, with at least one pressure sensor installed in a closed exit port of the bladder. The multiple cells of the bladder are formed by a pattern of spot welds between the top and bottom layers of the bladder, creating an array of generally circular or hexagonal cells between which the fluid can freely flow. The array of cells maximizes the pressure response for improved sensitivity, and minimizes the amount of fluid required to detect occupant weight, thereby minimizing the weight of the fluid-filled bladder. The pattern of spot welds in the vicinity of the pressure sensing location may be altered to reduce sensitivity to forces applied in proximity to the exit port.

Abstract: The present invention provides for a wheel alignment procedure for a vehicle having a steer-by-wire steering system. The wheel alignment procedure includes determining an offset alignment value for a road wheel of a vehicle. The offset alignment value may be determined as the difference between the sensed wheel angle and a measured true angular position of the road wheel. The method further includes the step of adjusting the road wheel position as a function of the offset alignment value. Accordingly, the vehicle road wheel can be aligned by adjusting a calibration value in a controller without requiring physical adjustment of a mechanical linkage.

Abstract: The ignition coil driver module of the present invention includes a control integrated circuit, formed of a low voltage semiconductor material, and a high current load driver integrated circuit, formed of a high voltage integrated circuit, housed within a common package. The high current load driver integrated circuit is responsive to a low voltage drive signal provided by the control integrated circuit to permit a load current to flow unrestricted through the load driver integrated circuit and an inductive load connected thereto. The control integrated circuit includes a sense resistor which receives the load current from the high current load driver integrated circuit, converts this current to a sense voltage, compares the sense voltage to a reference voltage generated within the control integrated circuit, and forces the low voltage drive signal to drop to a level which will limit the load current to a predetermined current value.

Abstract: In preferred embodiment, a mirror having selectively lightable indicia, including: a substrate of a substantially optically clear material; an optically reflective, optical filter layer disposed on a rear surface of the substrate, the optical filter layer providing at least one relatively narrow bandpass through which light can pass; a plurality of light sources disposed behind the optical filter layer, the plurality of light sources producing light in at least one relatively narrow range of frequencies substantially coincident with the at least one relatively narrow bandpass, such that light from the plurality of light sources can pass through the optical filter and thence through the substrate; and the optical filter layer reflecting, through the substrate, essentially all incident ambient light.

Abstract: A differential pressure sensor (10) having a housing 12 and a metal or alloy isolator (14) for stress isolation of a sensing cell (28) that is mounted to the isolator (14). The metal or alloy isolator (14) has an opening (16) therein for providing access to the sensing cell (28). The housing (12) is molded around the isolator (14) creating a seal therebetween and isolating the sensing cell (28).

Abstract: A method for rejecting system-to-system interference in a FLR system in which sampled data obtained from each channel of the FLR receiver is analyzed to recognize transient data due to interference with another FLR system and bounded in the time domain. The bounded data set is deleted and replaced with a new data set determined by interpolation. The transient data is recognized when the variance of a sliding window of samples exceeds a variance threshold. The method removes transient pulses with minimal distortion of the raw data, and the impact on system complexity and cost is minimal when the system already includes digital signal processing capability for other purposes.

Abstract: An improved obstacle detection radar system and method of operation in which the detection sensitivity is normalized with respect to target range without significantly increasing system complexity or cost, while at same time improving the system response time. The system consecutively integrates the received radar illumination corresponding to each of several contiguous range bins over different dwell intervals specific to the respective range bins. In particular, the dwell intervals are progressively reduced for the range bins nearest the system antennas, thereby reducing the detection sensitivity in those range bins, and at the same time, reducing the time required to completely scan all of the range bins. As a result, the signal attributable to the side-lobe patterns is inherently attenuated, the sensitivity is more normalized, and system response time is improved.

Abstract: A weight estimation apparatus for the passenger seat of a motor vehicle, in which a single bladder substantially encompassing the seat bottom is evacuated and then inflated with a known volume of air. The average pressure in the bladder is determined to estimate the passenger weight. According to a first embodiment, the apparatus continues to monitor the average pressure, and the process is re-initiated if the average pressure changes by at least a predetermined percentage. According to a second embodiment, a bleed valve allows the pressure in the bladder to slowly escape, and the apparatus monitors the rate of change in pressure as a corresponding indication of passenger weight; in this embodiment, the process of evacuating and inflating is re-initiated if the monitored change in pressure does not correspond with the estimated weight.

Abstract: A pressure port for attaching a stainless steel high pressure sensor to an automotive pressure line includes a cold rolled steel ring having a hex-shaped perimeter and a central bore, and a stainless steel stud welded in the ring. A flange of the stud abuts one face of the ring and an interlocking feature between the stud and the ring relieves stress on the weld during installation and removal of the assembly. An end of the stud extends beyond the ring and is threaded for attachment to the housing of a pressure vessel.

Abstract: A method of preventing solder reflow of a SMT component (14) attached with solder (22) to a circuit board (10) that subsequently undergoes a wave soldering operation. The method generally entails the use of a thermal shield (18, 28) that is either part of the support structure (12) for the circuit board (10) during the wave soldering operation, or a temporary mask (28) applied directly to a surface of the circuit board (10). In each case, the thermal shield (18, 28) is configured to contact and completely cover a limited surface region of the circuit board (10) directly opposite the SMT component (14). To provide adequate thermal protection, the covered surface region is preferably as large as or larger than the surface area of the component (14). In a preferred embodiment, the perimeter of the thermal shield (18, 28) has a tapered thickness, e.g., a beveled edge, that enables uninterrupted wave soldering of the surface surrounding the thermal shield (18, 28).