摘要:
The present invention provides a method for tiling an integrated circuit having a critically matched device such as a transistor. The method obtains an advantage of automatically improving metallic density over critically matched devices thus yielding improved CMP. The method may include the steps of: identifying critically matched devices in the integrated circuit; placing metal tiles over the critically matched device; performing a density test around each critically matched device; and if a density test is not satisfied around a critically matched device, placing at least one metal strip over a critically matched device.
摘要:
A method for placing tiles in an integrated circuit has matched devices that includes the steps of (1) calculating a metal spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (2) calculating a lateral spacing for tiles to be placed adjacent to the matched device in the integrated circuit; (3) placing tiles about the matched device based on the metal spacing and the lateral spacing; (4) performing a density test in an area around the matched device; and (5) if a density test is not satisfied in the area around the matched device, dividing the matched device into at least two subdevices and repeating, with respect to each subdevice, the steps of calculating a metal spacing, calculating a lateral spacing, and placing tiles about each subdevice. The method is further adaptable to various kinds of matched devices including poly resistors, diffused resistors, double-poly capacitors, metal-insulator-metal capacitors, and fringe capacitors.
摘要:
In accord with one aspect of the invention, an apparatus for illuminating and magnifying an object in a sterile field for observation is provided. A holder is mounted at one end of a base assembly. A magnifying lens is mounted to the holder and defines a field of vision. A light is attached to the holder by an attaching means in a predetermined spatial relationship with the lens such that the light directs a beam of light into the field. A method is provided for illuminating and magnifying an object in a sterile field without contaminating the sterile field. The base assembly and the holder are sterilized. The base assembly is positioned in the sterile field. A sterile pack containing the light in a sterilized condition is opened and the light is moved into the sterile field. The light is inserted into the opening of the holder. The light is actuated and provides a light beam. The magnifying lens is removed from a sterile pack and moved into the sterile field. The lens is attached to the holder in a predetermined spatial relationship with the light such that the lens defines a field of vision which the light beam intersects. An object is brought into the field of vision.
摘要:
A circuit for generating a plurality of timing signals includes a plurality of cascade-connected delay cells, each having an input coupled to an output of another, and a plurality of latches. Set inputs of various latches are coupled to outputs of various delay cells to determine times of occurrence of leading edges of various timing pulses. Reset inputs of the various latches are coupled to outputs of various delay cells to determine times of occurrence of trailing edges of various timing pulses. The circuit includes a phase detector having a first input coupled to receive a clock signal and a second input coupled to an output of one of the delay cells to receive a signal indicative of propagation of a logic state through a first group of the delay cells, to produce an adjustment signal indicative of whether the phase of the indicator signal is ahead of or behind the phase of the clock signal. Each of the delay cells increases or decreases propagation time through that delay cell in response to the adjustment signal, so as to cause a time required for the logic state to propagate through all of the delay cells to be equal to a period of the clock signal.
摘要:
A method and an improved eductor apparatus for producing ultrafine explosive particles is disclosed. The explosive particles, which when incorporated into a binder system, have the ability to propagate in thin sheets, and have very low impact sensitivity and very high propagation sensitivity. A stream of a solution of the explosive dissolved in a solvent is thoroughly mixed with a stream of an inert nonsolvent by obtaining nonlaminar flow of the streams by applying pressure against the flow of the nonsolvent stream, to thereby diverge the stream as it contacts the explosive solution, and violently agitating the combined stream to rapidly precipitate the explosive particles from the solution in the form of generally spheroidal, ultrafine particles. The two streams are injected coaxially through continuous, concentric orifices of a nozzle into a mixing chamber. Preferably, the nonsolvent stream is injected centrally of the explosive solution stream. The explosive solution stream is injected downstream of and surrounds the nonsolvent solution stream for a substantial distance prior to being ejected into the mixing chamber.
摘要:
High speed conversion of an analog input signal to a digital output signal is performed by applying the analog input to an input of a unity gain amplifier. During a first pass, an output signal produced by the amplifier is applied to inputs of each of a plurality of comparators. A first group of successively larger reference voltages are applied to reference inputs of the comparators, respectively. A plurality of the comparators switch in response thereto to produce output signals indicative of a range within which the output of the amplifier lies. The outputs of the comparators are encoded to effectuate conversion thereof to an analog representation of the amplifier output. The analog representation is compared to the analog input signal and the difference therebetween is applied to the input of the amplifier. During another pass another group of reference voltages, each substantially lower than corresponding values thereof during the previous pass, are applied to the reference inputs of the comparators. Binary representations of the outputs of the comparators during each of the passes are combined into a binary word accurately representing the analog input signal.
摘要:
A control method and apparatus for a metal-forming machine such as a cold heading machine are described. The described method and apparatus monitor machine operation during production and permit relatively large deviations from a prescribed norm over a short term without shutting down the machine, while ensuring longer term compliance to relatively small tolerances from the norm. The described controller first determines an average of a measured parameter such as the hit energy applied to a group of workpieces resulting in acceptable metal-forming during a training mode and then stores this average as a target value. The controller then establishes a set of tolerance windows to be used to control forming operations in a production mode.In production, the controller repeatedly measures the machine parameter and then compares selected averages of the measured parameter with the target value and the respective tolerance window, and indicates out-of-tolerance condition whenever one of the selected average falls outside the respective window. The tolerance windows are selected such that short term averages or single values of the measured parameter must deviate from the target values by larger amounts than long term averages before the controller signals an out-of-tolerance condition. For example, the described controller operates to interrupt machine operation when a single measured value of hit energy deviates by more than 16% from the learned target value, when a group of 4 measured values of hit energy deviates by more than 8%, when a group of 16 measured values of hit energy deviates by more than 4%, or when a group of 64 measured values of hit energy deviates by more than 1%.The disclosed controller also signals when the measured parameter is nearing an out-of-tolerance condition, and it acts to change the target value gradually during a warmup period of machine operation in order to reduce the number of unnecessary interruptions of machine operation.
摘要:
A teaching device includes a reading station provided with six on-off switches for automatically sensing a text key encoded as a pattern of punched holes in a text book. The teaching device automatically generates an answer key from the text key by means of a pseudo-random number generator which is run using the text key as a seed. The text book includes a number of multiple choice questions in which the correct answer corresponds to the answer designated in the answer key.
摘要:
A system and apparatus for reducing the effects of circuit mismatch in analog-to-digital converters is disclosed. In one form, an analog-to-digital converter (ADC) includes a switching network operable to couple an analog input received by a sample and hold module to a folding amplifier operable to process the analog input. The ADC further includes an averaging resistive network coupled to the folding amplifier and operable to provide an output representative of a portion of the analog input received by the folding amplifier to produce a digital representation of the analog input.
摘要:
A system and apparatus for reducing offset voltages in folding amplifiers is disclosed. In one form, a folding amplifier for use in an analog-to-digital converter is provided. The folding amplifier includes a first current source operable to be coupled to a first differential pair and a second differential pair. The folding amplifier further includes a switching network coupled between the first current source and the first and second differential pairs and operable to enable coupling the first current source to at least one of the first differential pair and the second differential pair.