Brooktree Corporation

Diatron Corporation

Iedsco Oy

Enguvu Ag/sa/ltd.

Henry S Katzenstein

Christopher D James

Walter B Dandliker

Keith R Watson

Howard S Barr

A bridging member extending across a cavity in a semiconductor substrate (e.g. signal crystal silicon) has successive layers--a masking layer, an electrically conductive layer (e.g. polysilicon) and an insulating layer (e.g. SiO.sub.2). A first electrical contact (e.g. gold coated with ruthenium) extends on the insulating layer in a direction perpendicular to the extension of the bridging member across the cavity. A pair of bumps (e.g. gold) are on the insulating layer each between the contact and one of the cavity ends. Initially the bridging member and then the contact and the bumps are formed on the substrate and then the cavity is etched in the substrate through holes in the bridging member. A pair of second electrical contacts (e.g. gold coated with ruthenium) are on the surface of an insulating substrate (e.g. pyrex glass) adjacent the semiconductor substrate. The two substrates are bonded after the contacts are cleaned. The first contact is normally separated from the second contacts because the bumps engage the insulating substrate surface. When a voltage is applied between an electrically conductive layer on the insulating substrate surface and the polysilicon layer, the bridging member is deflected so that the first contact engages the second contacts. Electrical leads extend on the surface of the insulating substrate from the second contacts to bonding pads disposed adjacent a second cavity in the semiconductor substrate. The resultant relays on a wafer may be separated by sawing the semiconductor and insulating substrates at the position of the second cavity in each relay to expose the pads for electrical connections.

Micromachined relay and method of forming the relay

A bridging member extending across a cavity in a semiconductor substrate (e.g. single crystal silicon) has successive layers--a masking layer, an electrically conductive layer (e.g. polysilicon) and an insulating layer (e.g. SiO.sub.2). A first electrical contact (e.g. gold coated with ruthenium) extends on the insulating layer in a direction perpendicular to the extension of the bridging member across the cavity. A pair of bumps (e.g. gold) are on the insulating layer each between the contact and one of the cavity ends. Initially the bridging member and then the contact and the bumps are formed on the substrate and then the cavity is etched in the substrate through holes in the bridging member. A pair of second electrical contacts (e.g. gold coated with ruthenium) are on the surface of an insulating substrate (e.g. pyrex glass) adjacent the semiconductor substrate. The two substrates are bonded after the contacts are cleaned. The first contact is normally separated from the second contacts because the bumps engage the insulating substrate surface. When a voltage is applied between an electrically conductive layer on the insulating substrate surface and the polysilicon layer, the bridging member is deflected so that the first contact engages the second contacts. Electrical leads extend on the surface of the insulating substrate from the second contacts to bonding pads disposed adjacent a second cavity in the semiconductor substrate. The resultant relays on a wafer may be separated by sawing the semiconductor and insulating substrates at the position of the second cavity in each relay to expose the pads for electrical connections.

A reader transmits a pulse to a transponder. The transponder responds by transmitting a particular number (e.g. 10) of signals at a frequency dependent upon the identifying code recorded in the transponder. The reader then transmits a pulse of an opposite polarity to that previously transmitted. The transponder responds by generating 10 signals at a second frequency different from the first frequency. In this way, sequences of pulses alternatively of opposite polarity are transmitted by the reader and sequences of signals at the first and second frequencies are transmitted by the transponder. The reader decodes the sequences of signals at the first and second frequencies, in accordance with the order of the frequencies of such signals, to identify the code at the transponder. The transponder may have a programmable memory to store the code. To program the memory with such a code, the reader transmits sequences of pulses, each sequence coding for a programmable item of information (e.g. binary '1', binary '0' and reset). Depending upon the individual programmable item, the coded sequences may have pulses of the same polarity or of opposite polarity. At a time related to each such sequence, the reader produces a sequence different from the coded sequence to indicate that pulses coding for a programmable item follow. The transponder decodes the transmitted pulses to recover the identifying code. This code is recorded in the programmable memory and is used to identify the transponder when the reader interrogates the transponder as described above.

Programmable memory for an encoding system

Apparatus converts into an analog value signals representing digital values. Sub-sets of switches are provided, the number of switches in each sub-set being directly related to the digital significance of the switches in such sub-set. The switches in each sub-set may be paired to provide for a conductivity of one switch in each pair. The signals representing individual digital values are introduced to the associated sub-sets to provide for the conductivity of an individual one of the switches in each pair in accordance with the digital value represented by such signals. The switches are connected in a recursive relationship defined by repetitions of a basic block. Each basic block is in turn defined by a pair of basic sub-blocks. A plurality of capacitors are also provided as output members. The capacitors are connected to the recursive relationship of the switches to charge the capacitors through paths defined by the conductive ones of the switches. When the capacitors are conductive, the switches operate to introduce the charge from the capacitors to one of two output lines. For progressive increases in the digital value, a progressive number of the capacitors are connected to a particular one of the output lines, and capacitors previously connected to the particular output line are maintained connected to the output line with such progressive increases in the digital value. The cumulative current through the particular output line is indicative of the analog value.

Apparatus for converting data between digital and analog values

First terminals are equally spaced on a substantially uniformly resistive thin film at or near a first side edge of the film at progressive positions downwardly from the top of the film. Near the bottom of the film, second terminals are preferably equally spaced progressively inwardly from the first side edge of the film. An energizing potential is applied to the film either at the corner defined by the top and the first side edge of the film or in a curved pattern of positions near such corner. A reference potential (e.g. ground) is applied to the film near the otherside of the film and near the bottom edge of the film. Voltages are thus produced at the successive ones of the first terminals with an exponential relationship with respect to such terminal positions and at the successive ones of the second terminals with a linear relationship with respect to such terminal positions. The disposition of the second terminals may be compensated for deviations in a logarithmic response in an output member (e.g. an electron gun in a cathode ray tube) receiving the voltages on such terminals. Cuts may be provided from the other side edge of the resistive surface in a horizontal direction partially toward the first side edge of the resistive surface to decrease the width of the resistive surface. Each of a plurality of comparators receives an input voltage first and second and the voltage at an individual one of the terminals. The comparators provide an output indicative of magnitude of the input voltage.

Non-linear analog to digital converter

A plurality of equally spaced terminals may be disposed at a side edge of a substantially uniformly resistive thin film. A reference potential (e.g. ground) may be applied to the second side of the film. An energizing voltage may be applied at the juncture between the first side edge and a particular one of the top and bottom edges of the film. In this way, the successive terminals receive voltages with a logarithmic relationship relative to the terminal positions. When a linear relationship of voltages is desired at successive terminals in a low range, no reference potential is applied to the second side edge of the thin film. Instead, the other one of the top and bottom edges may receive the reference voltage. Alternatively no reference voltage may be applied and terminals indicating the linear voltages may be disposed at such other edge. Each of a plurality of comparators providing an output indicative of the input voltage receives an input voltage and the voltage at an individual one of the successive terminals. The voltages in the logarithmic portion of the thin film may be calibrated by a circuit including a capacitance to indicate voltage deviations from the logarithmic relationship. The successive terminal voltages in the linear portion of the film may be calibrated by the capacitance circuit and a constant current source to indicate voltage deviations from the linear relationship.

Flash analog-to-digital converter with logarithmic/linear threshold

A variable electrical current in a first winding on a magnetizable core produces a magnetomotive force in the core. A second core winding produces an opposing magnetomotive force digitally adjustable periodically by a third core winding, a pair of switches and a flip-flop coupled to a center tap for alternately closing such switches when triggered to opposite states. The flip-flop is triggered between opposite states when the third winding current reaches a particular magnitude. In each cycle, the time differences for producing the particular magnitudes and the opposite polarities are dependent upon the remanent core flux. Such time differences are counted digitally upwardly and downwardly for opposite polarities. The second winding current is adjusted digitally in each cycle in a direction to minimize such count. The magnitudes of successive adjustments may be compared periodically by adaptive tracking techniques to control the magnitudes of subsequent adjustments. With large magnitudes of the variable current, the first winding on the core may receive a stepped-down current from a first winding on a second core having a second winding to receive the variable current. Windings on the first and second cores may be connected in a closed loop, or windings on a third core produce in the first core a magnetomotive force aiding the magnetomotive force from the current in the second winding on the second core to compensate for energy losses as a result of such current. The second core may be notched to prevent core becoming saturation.

Current meter

A fluorometer for measuring a particular fluorescence emanating from a specimen and operating in accordance with the following method. Producing a burst of concentrated light energy and directing the concentrated light energy toward the specimen to produce a fluorescence from the specimen including the particular fluorescence. Preferably producing an image of the fluorescence. Detecting the fluorescence and producing a signal in accordance with the fluorescence. Controlling the passage of the image of the fluorescence for detecting within a particular time period so as to optimize the detection of the particular fluorescence. Timing the operation to sequence the detection of the fluorescence within the particular time period after the production of the burst of concentrated light energy. Scanning the fluorescence from the specimen for forming signals representative of the fluorescence from the specimen. Analyzing the signals to enhance the portion of the signal representing the particular fluorescence relative to the portion of the signal.

Fluorometer

Sub-sets of switches are provided each having a number of switches directly related to an individual bit in a binary coded input word. Signals representing the individual bits are introduced to the switches in the different sub-sets to obtain switch conductivities in accordance with such binary bits. The switches are connected in a repetitive array to provide paths through the conductive ones of the switches. The switches are connected to output members and a line to introduce the current through the output members to the line in accordance with the pattern of switch conductivities. This provides for progressive increases in the number of the output members connected to the line, ad for a continued connection to the line of output members previously connected to the line, with progressive increases in the binary value. The cumulative current through the line is indicative of the analog value. Additional circuitry may provide an indication of the reduced binary values relative to the binary values represented by the switches. An interpolation line may be connected to the repetitive array to receive a current from the output member to be connected next to the line for increasing binary values. The interpolation line and the additional circuitry may be connected to provide a current from such circuitry in accordance with the reduced binary values and to introduce such current to the line to provide an output current on the line in representation of the analog value. The additional circuitry may constitute another repetitive array.

Apparatus for converting data between analog and digital values

A reader identifies information, such as the identity of an object at a transponder, provided in binary form by the transponder. The reader initially generates a pulse which activates the transponder into transmitting a series of signals, such as by magnetic induction, to the reader. Upon each count of a particular number of signals in the reader, the reader generates an additional pulse which causes the transponder to transmit a new series of signals to the reader. The generation of the pulses by the reader may occur through the charge and discharge of energy in a storage member such as a capacitance. The series of signals produced by the transponder may have either a first frequency or a second frequency. The signals may be generated in each sequence at the first and second frequencies in an order dependent upon (a) the binary code identifying the object at the transponder and (b) the polarity of the pulse produced by the transponder in such sequence. The reader then identifies the information by demodulating the signals received by it at the first and second frequencies. The reader is able to interrupt at any time the generation of the sequence of signals at the transponder when it does not receive the signals transmitted by the transponder. The reader then operates on a free running basis to generate pulses of opposite polarity at a relatively low frequency.

Identification system

First and second switches such as transistors are connected to a charge storage member such as a capacitance. The capacitance is charged through the first transistor from a positive supply when the transistor becomes conductive. The capacitances is discharged through the second transistor to a reference potential such as ground when the second transistor becomes conductive. The conductivities of the first and second transistors are controlled by pulses from a pulse source such as a transformer. The transformer primary produces a pulse of one polarity upon the occurrence of the leading edge of an input signal and a pulse of an opposite polarity upon the occurrence of the trailing edge of the input signal. Two secondary windings are respectively connected in opposite polarities to the bases of the first and second transistors to provide for the conductivity of only one of the transistors at any one time. The transformers saturate the conductive transistor to prolong on a limited basis the time during which the transistor remains conductive. The other one of the transistors is made instantaneously non-conductive by providing for an instantaneous discharge of the stored base charge between the base and emitter of the transistor. A constant current source is electrically in parallel with the first transistor to sustain the capacitance charge at a high level after the limited period of time in which the first transistor remains conducitive. A low frequency transistor is connected in parallel with the second transistor to sustain the discharge of the capacitance after the limited period of time in which the second transistor remains conductive.

Growing community of inventors

Pacific Palisades, CA, United States of America

Henry S Katzenstein