Abstract:
Various semiconductor package arrangements and methods that improve the reliability of wire bonding a die to ground or other outside contacts are described. In one aspect, selected ground pads on the die are wire bonded to a bonding region located on the tie bar portion of the lead frame. The tie bar is connected to an exposed die attach pad that is downset from the bonding region of the tie bar. In some embodiments, the bonding region and the leads are at substantially the same elevation above the die and die attach pad. The die, bonding wires, and at least a portion of the lead frame can be encapsulated with a plastic encapsulant material while leaving a contact surface of the die attach pad exposed to facilitate electrically coupling the die attach pad to an external device.
Abstract:
An integrated circuit package is described that includes a substrate, a leadframe and one or more integrated circuits that are positioned between the substrate and the leadframe. Multiple electrical components may be attached to one or both sides of the substrate. The active face of the integrated circuit is electrically and physically connected to the substrate. The back side of the integrated circuit is mounted on a die attach pad of the leadframe. The leadframe includes multiple leads that are physically attached to and electrically coupled with the substrate. A molding material encapsulates portions of the substrate, the leadframe and the integrated circuit. Methods for forming such packages are also described.
Abstract:
A semiconductor chip package having multiple leadframes is disclosed. Packages can include a first leadframe having a first plurality of electrical leads and a die attach pad having a plurality of tie bars, a second leadframe generally parallel to the first leadframe and having a second plurality of electrical leads, and a mold or encapsulant. Tie bars can be located on three main sides of the die attach pad, but not the fourth main side. Gaps in the first and second plurality of electrical leads can be enlarged or aligned with each other to enable the elimination of mold flash outside the encapsulated region, which can be accomplished with mold cavity bar protrusions. Additional components can include a primary die, a secondary die, an inductor and/or a capacitor. The first and second leadframes can be substantially stacked atop one another, and one or both leadframes can be leadless leadframes.
Abstract:
The invention is related to a laser diode based multiple beam laser spot imaging system for characterization of vehicle dynamics. A laser diode based, preferably VCSEL based laser imaging system is utilized to characterize the vehicle dynamics. One or more laser beams are directed to the road surface. A compact imaging system including an imaging matrix sensor such as a CCD or CMOS camera measures locations or separations of individual laser spots. Loading status of vehicles and vehicles' pitch and roll angle can be characterized by analyzing the change of laser spot locations or separations.
Abstract:
The present invention relates to a method and device of measuring the velocity of a target (10) by laser self-mixing. An output beam (2) of a single laser source (1) is split into two sensing beams (4, 5). The two sensing beams (4, 5) are directed on different beam paths to a surface of the moving target (10), wherein said different beam paths are selected to be symmetrical to one another. From a measured intensity variation of the output beam (2) Doppler frequencies of laser radiation of the two sensing beams (4, 5) backscattered from the target (10) are determined. Based on these Doppler frequencies a vertical velocity of the moving target (10) is determined from a difference in the Doppler frequencies and a longitudinal velocity of the moving target (10) is determined from the sum of the Doppler frequencies. The invention allows a simple and low cost design of the device and a simple processing of the measurement signal.
Abstract:
A security system is described,comprising a sensor module (15) which accommodates a laser sensor(10)working with self-mixing interference. The laser sensor(10)generates measurement data which are related to the velocity of an object such as the body of a human being and,optionally,the distance between the laser sensor (10) and the object. Dependent on the measurement data assembled by the laser sensor (10)and supplied to a control circuit(30)such as an airbag computer, the airbag computer activate security means such as an airbag(35)in order to prevent injuries of the human body. Furthermore, a method of driving such a security system is described.
Abstract:
A variety of semiconductor package arrangements and packaging methods are described that improve the reliability of bonding wires that down bond a die to a die attach pad. In one aspect, selected portions of the top surface of a lead frame (which may be in panel form) are plated (e.g., silver plated) to facilitate wire bonding. The plating covers some, but not all of a die attach surface of the die attach pad. In some preferred embodiments, the plating on the die attach pad is arranged as a peripheral ring that surrounds an unplated central region of the die support surface. In other embodiments, the plating on the die attach pad takes the form of bars or other geometric patterns that do not fully cover the die support surface. Unplated portions of the die support surface are roughened to improve the adherence of the die to the die attach pad, thereby reducing the probability of die attach pad delamination and the associated risks to down bonded bonding wires. The described lead frames may be used in a variety of packages. Most commonly, a die is attached to the die support surface of the die attach pad and electrically connected to the lead frame leads by wire bonding as appropriate. At least one of the die's bond pads (typically the ground bond pad(s)) is down bonded to the die attach pad. The die, the bonding wires and at least portions of the lead frame are then typically encapsulated with a plastic encapsulant material while leaving a contact surface of the die attach pad exposed to facilitate electrically coupling the die attach pad to an external device.
Abstract:
The invention is related to laser diode based self-mixing laser sensors for simplified vehicle stability control. Vehicle's side slip angle, front and rear tire slip angles, yaw rate and lateral acceleration rate are derived explicitly from self-mixing laser sensors. Three criteria based on yaw rate, turn radius and tire slip angle analysis are employed to detect the occurrence of understeer or oversteer, which enables simplified vehicle electronic stability program.
Abstract:
A sensor module (1) for measuring the distance to a target and/or the velocity of the target (50), the sensor module (1) comprising at least one laser source (100), at least one detector (200) being adapted to detect modulated laser light and at least one control element the control element (400) being adapted to vary the focus point ofthe laser light and/or the intensity of the laser light and/or the direction of the laser light. The controlofthe laser light emitted by the laser source (100) either by active optical devices as variable focus lenses or controllable attenuators or passive optical elements in combination with arrays of laser sources (100) and detectors (200) enable flexible and robust sensor modules.
Abstract:
A security system is described,comprising a sensor module (15) which accommodates a laser sensor(10)working with self-mixing interference. The laser sensor(10)generates measurement data which are related to the velocity of an object such as the body of a human being and,optionally,the distance between the laser sensor (10) and the object. Dependent on the measurement data assembled by the laser sensor (10)and supplied to a control circuit(30)such as an airbag computer, the airbag computer activate security means such as an airbag(35)in order to prevent injuries of the human body. Furthermore, a method of driving such a security system is described.