摘要:
A test structure (200) provides defect information rapidly and accurately. The test structure includes a plurality of lines (201,208) provided in a parallel orientation, a decoder (202, 205) coupled to the plurality of lines for selecting one of the plurality of lines, and a sense amplifier coupled to the selected line. To analyze an open, a line in the test structure is coupled to the sense amplifier. A high input signal is provided to the line. To determine the resistance of the open, a plurality of reference voltages are then provided to the sense amplifier. A mathematical model of the resistance of the line based on the reference voltage provided to the sense amplifier is generated. Using this mathematical model, the test structure can quickly detect and characterize defect levels down to a few parts-per-million at minimal expense.
摘要:
A programmable after-package, on-chip reference voltage trim circuit for an integrated circuit having a plurality of programmable trim cells generating a programmed sequence. A converter is provided to convert the bit sequence into a trim current. The trim current is added to an initial value of a reference voltage to be trimmed, as generated by the integrated circuit. Once the correct value of the trim current is determined, isolation circuitry is programmed to isolate the trim circuitry from the remainder of the IC, thereby freeing the logic and package pins associated with the IC for use by users of the IC. The preferred trim circuitry includes fuses which are blown in accordance with a bit value supplied to the trim cell to permanently fix a trim current value, once a best fit value is determined.
摘要:
A printed circuit board (10) has a first image (11). In the first image (11) there is a first ball grid array pattern (61) for attaching a first input/output ball grid array package. The first ball grid array pattern (61) includes a de-populated center area. A first surface insulation resistance pattern (62) is laid out within the de-populated center area of the first ball grid array pattern (61). A second ball grid array pattern (24) also may be contained within the first image (11). The second ball grid array pattern (24) is for attaching a second input/output ball grid array package. The second ball grid array pattern (24) has rows of interconnect pads (81). A second surface insulation resistance pattern (82) is laid out between the rows of interconnect pads (81).
摘要:
A circuit arrangement includes a wear detector which is proportioned or which operates so that it "wears faster" than the other parts of the circuit arrangement. To the wear detector there is connected an indicator which, when the wear detector ceases to function, indicates that the circuit arrangement is to be replaced.
摘要:
A test system having improved means for reducing driver switching (delta I) noise. The test system employs a tester connected to and electrically testing an integrated circuit device, such as a logic chip. The integrated circuit device has a plurality of input terminals (R5-R54) for receiving an electrical test pattern from the tester. The integrated circuit device also includes a plurality of output driver circuits (D2-D1O2) having outputs connected to the tester. The test system is characterized in that said integrated circuit device includes a driver sequencing circuit (L1-L1O) responsive to at least one control signal (R1-R4) from said tester to sequentially condition said driver circuits for possible switching, whereby delta I noise is reduced during testing.
摘要:
A floating sampler and directional bridge for use in characterizing the impedance of an integrated device under test from D.C. up to frequencies above 100 GHz. The directional bridge has the structure of a Wheatstone bridge with resistor values selected such that when the input impedance of the device under test matches the output impedance of the source, no voltage develops across two nodes of the bridge. When no impedance match exists, a floating diode/capacitor sampler comprised of two diode/capacitor pairs (D1, C1 ; D2, C2) driven by local oscillator (147) strobe pulses samples the voltage difference between the two nodes of the bridge and outputs an IF signal proportional to the difference. Another pair of diode/capacitor samples (D3, C3; D4, C4) outputs an IF signal proportional to the amplitude of the RF excitation waveform.
摘要:
An LSI system includes: a multi-layer print board (300); and a plurality of LSI circuit chips (100 to 103) mounted on the multi-layer printed circuit board, each including a plurality of pins (E,520), a reference voltage terminal (F), a pin scan out terminal (G) and a plurality of pin scan out circuits (130i) corresponding to the pins on a one-to-one basis. The multi-layer printed circuit board includes a reference voltage feeding layer (310) formed therein in a form of a mesh or a sheet. By electrically connecting each reference voltage terminal of the plurality of LSI circuit chips to the reference voltage feeding layer, a substantially equal reference voltage can be fed to each LSI and a voltage drop thereof is reduced.
摘要:
A new and improved method and apparatus for profiling wafers (100), and for uniquely identifying the dies formed thereon, wherein the method includes the step of locating a set of reference points (110, 111) along the periphery of the wafer, relative to a predetermined coordinate system. Next, the equation of a hypothetical circle which substantially contours the periphery of the wafer, and which passes through the reference points, is defined. The coordinates (a,b) of the center (120) of the hypothetical circle, as well as the coordinates of an arbitrary reference die (102) on the wafer, are then derived from the equation of the hypothetical circle. Subsequently, the entire surface of the wafer is mapped relative to the center or to the reference die, by utilizing predetermined stepping dimensions.
摘要:
Zur Erzeugung von hochfrequenten impulsförmigen Ausgangssignalen einstellbarer Grundlinienspannung und Amplitudenspannung aus Eingangssignalen, insbesondere in Prüfeinrichtungen, ist eine Anordnung vorgesehen, die eine Eingangsstufe (EST), eine Konstantstromquellenschaltung (KSQ) und eine Pegelbegrenzungsschaltung (SST) enthält. Die Eingangsstufe (EST) erzeugt mit Hilfe zweier Differenzverstärker(DV1, DV2) zwei Steuersignale, die den in der Konstantstromquellenschaltung (KSO) enthaltenen Konstantstromquellen (KQ1, KQ2) zugeführt werden. Bei Vorliegen des einen Steursignals wird die eine Konstantstromquelle (KQ1) eingeschaltet und liefert den ersten Konstantstrom (lK1 Bei Vorliegen des anderen Steuersignals wird die zweite Konstantstromquelle (KQ2) eingeschaltet und liefert den zweiten Konstantstrom (lK2). Die Konstantströme (lK1, IK2), die abwechselnd auftreten, fließen entweder über einen ersten Gleichrichter (G1) oder über einen zweiten Gleichrichter (G2) und über einen ersten Transistor (T3) oder einen zweiten Transistor (T4) der Pegelbegrenzungsschaltung (SST). Die beiden Gleichrichter (G1, G2) sind miteinander verbunden und bilden den Ausgang (A4). An der anderen Anschlußklemme (VP2, VP3) der Gleichrichter (G1, G2) liegt ein Potential, das über einen Operationsverstärker (OP1, OP2) und den Transistor (T3, T4) von einer Steuerspannung (VL, VH) festgelegt wird. Durch Änderung der Steuerspannungen (VL, VH) wird das Potential an den Anschlußklemmen (VP2, VP3) eingestellt und damit am Ausgang (A4) die Spannung für die Amplitude und für die Grundlinie des Ausgangssignals (AS) erzeugt.